Marek G Zreda

Interests

Teaching

Hydrogeology, water resources, hydrology, field methods in hydrology, cosmogenic isotopes in earth sciences, applied cosmic-ray physics.

Research

Hydrology, paleoclimate, geochronology, cosmogenic isotope geochemistry, glacial geology, Quaternary geology and climate, glaciations, paleohydrology, applied cosmic-ray physics, earth surface moisture, geophysical methods, land-surface processes, remote sensing.

Courses

Scholarly Contributions

Chapters

• Andreasen, M., Looms, M. C., Jensen, K. H., Sonnenborg, T. O., Bogena, H., Desilets, D., & Zreda, M. (2014). Cosmic-ray neutron intensity measurements of soil moisture – a case study in the Skjern catchment, Denmark. In Society of Exploration Geophysicists Annual Meeting, 26-31 October 20014, Denver, Colorado, USA(pp 5 pp.).
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  Research paper on using cosmic-ray neutrons to measure soil moisture in dense forest.
• Andreasen, M., Looms, M. C., Jensen, K. H., Sonnenborg, T. O., Bogena, H., Desilets, D., & Zreda, M. (2014). Cosmic-ray neutron intensity measurements of soil moisture – a case study in the Skjern catchment, Denmark. In Society of Exploration Geophysicists Annual Meeting, 26-31 October 2014, Denver, Colorado, USA(pp 5 pp.).
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  Research paper on using cosmic-ray neutrons to measure soil moisture in dense forest.
• Desilets, D., & Zreda, M. (2014). Cosmic-ray hydrometrology: Measuring soil moisture with cosmic-ray neutrons. In Encyclopedia of Remote Sensing: Springer Reference.
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  Encyclopedia entry for cosmic-ray sensing of soil moisture.
• Franz, T. E., Zreda, M., & King, E. G. (2014). Cosmic-ray soil moisture probe: A new technology to manage African dryland ecosystems. In Proceedings - International Symposium on Managing Soils for Food Security and Climate Change Adaptation and Mitigation(pp 381-386). Rome: Food and Agriculture Organization of the United Nations.
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  Research and review paper on cosmic-ray soil moisture sensing.
• Zreda, M. G., & Phillips, F. M. (2013).

  Cosmogenic Nuclide Buildup in Surficial Materials

  . In Quaternary Geochronology: Methods and Applications. American Geophysical Union (AGU). doi:10.1029/RF004P0061

Journals/Publications

• Bogena, H. R., Schr??n, M., Jakobi, J., Ney, P., Zacharias, S., Andreasen, M., Baatz, R., Boorman, D., Duygu, M. B., Eguibar-Gal??n, M., Fersch, B., Franke, T., Geris, J., Gonz??lez, S. M., Kerr, Y., Korf, T., Mengistu, Z., Mialon, A., Nasta, P., , Nitychoruk, J., et al. (2022). COSMOS-Europe: a European network of cosmic-ray neutron soil moisture sensors. Earth System Science Data, 14(3), 1125-1151.
• Badiee, A., Blake, J. R., Cielniak, G., Cooper, H., Evans, J. G., Fentanes, J. P., Köhli, M., Pearson, S., Scarlet, P., Trill, E., Wallbank, J. R., Zhu, Y., & Zreda, M. (2021).

  Using Additional Moderator to Control the Footprint of a COSMOS Rover for Soil Moisture Measurement

  . Water Resources Research, 57(6). doi:10.1029/2020wr028478
• Badiee, A., Wallbank, J. R., Fentanes, J. P., Trill, E., Scarlet, P., Zhu, Y., Cielniak, G., Cooper, H., Blake, J. R., Evans, J. G., Zreda, M., Köhli, M., & Pearson, S. (2021). Using Additional Moderator to Control the Footprint of a COSMOS Rover for Soil Moisture Measurement. Water Resources Research, 57(6).
• Dorigo, W., Himmelbauer, I., Aberer, D., Schremmer, L., Petrakovic, I., Zappa, L., Preimesberger, W., Xaver, A., Annor, F., Ardö, J., Baldocchi, D., Bitelli, M., Blöschl, G., Bogena, H., Brocca, L., Calvet, J., Camarero, J. J., Capello, G., Choi, M., , Cosh, M. C., et al. (2021). The International Soil Moisture Network: Serving Earth system science for over a decade. Hydrology and Earth System Sciences, 25(11), 5749-5804.
• Andreasen, M., Bogena, H., Desilets, D., Jensen, K. H., Looms, M. C., & Zreda, M. (2020).

  Cosmic Ray Neutron Soil Moisture Estimation Using Physically Based Site‐Specific Conversion Functions

  . Water Resources Research, 56(11). doi:10.1029/2019wr026588
• Andreasen, M., Jensen, K. H., Bogena, H., Desilets, D., Zreda, M., & Looms, M. C. (2020). Cosmic Ray Neutron Soil Moisture Estimation Using Physically Based Site-Specific Conversion Functions. Water Resources Research, 56(11).
• Fersch, B., Francke, T., Heistermann, M., Schrön, M., Döpper, V., Jakobi, J., Baroni, G., Blume, T., Bogena, H., Budach, C., Gränzig, T., Förster, M., Güntner, A., Franssen, H., Kasner, M., Köhli, M., Kleinschmit, B., Kunstmann, H., Patil, A., , Rasche, D., et al. (2020). A dense network of cosmic-ray neutron sensors for soil moisture observation in a highly instrumented pre-Alpine headwater catchment in Germany. Earth System Science Data, 12(3), 2289-2309.
• Sarıkaya, M., Çiner, A., Zreda, M., Şen, E., & Ersoy, O. (2019). Chlorine degassing constrained by cosmogenic 36Cl and radiocarbon dating of early Holocene rhyodacitic lava domes on Erciyes stratovolcano, central Turkey. Journal of Volcanology and Geothermal Research, 369, 263-275.
• Chan, S. K., Bindlish, R., O'Neill, P., Jackson, T., Njoku, E., Dunbar, S., Chaubell, J., Piepmeier, J., Yueh, S., Entekhabi, D., Colliander, A., Chen, F., Cosh, M. H., Caldwell, T., Walker, J., Berg, A., McNairn, H., Thibeault, M., Martínez-Fernández, J., , Uldall, F., et al. (2018). Development and assessment of the SMAP enhanced passive soil moisture product. Remote Sensing of Environment, 204, 931-941.
• Andreasen, M., Jensen, K. H., Desilets, D., Franz, T. E., Zreda, M., Bogena, H. R., & Looms, M. C. (2017). Status and perspectives on the cosmic-ray neutron method for soil moisture estimation and other environmental science applications. Vadose Zone Journal, 16(8).
• Andreasen, M., Jensen, K. H., Desilets, D., Zreda, M., Bogena, H. R., & Looms, M. C. (2017). Cosmic-ray neutron transport at a forest field site: The sensitivity to various environmental conditions with focus on biomass and canopy interception. Hydrology and Earth System Sciences, 21(4), 1875-1894.
• Andreasen, M., Jensen, K., Desilets, D., Franz, T., Zreda, M. G., Bogena, H., & Looms, M. (2017). Status and perspectives on the cosmic-ray neutron method for soil moisture estimation and other environmental science applications. Vadose Zone Journal, 16(8). doi:10.2136/vzj2017.04.0086
• Chan, S., others, 3., Zreda, M. G., & others, 3. (2017). Development and Validation of The SMAP Enhanced Passive Soil Moisture Product. IEEE International Geoscience and Remote Sensing Symposium (IGARSS 2017), 4.
• Montzka, C., Bogena, H. R., Zreda, M., Monerris, A., Morrison, R., Muddu, S., & Vereecken, H. (2017). Validation of Spaceborne and Modelled Surface Soil Moisture Products with Cosmic-Ray Neutron Probes. REMOTE SENSING, 9(2).
• Montzka, C., Bogena, H. R., Zreda, M., Monerris, A., Morrison, R., Muddu, S., & Vereecken, H. (2017). Validation of spaceborne and modelled surface soil moisture products with Cosmic-Ray Neutron Probes. Remote Sensing, 9(2).
• O'neill, P. E., Chan, S., Bindlish, R., Chaubell, J., Piepmeijer, J., Dunbar, A., Cosh, M. H., Colliander, A., Chen, F., Entekhabi, D., Yeuh, S., Caldwell, T. G., Walker, J. P., Wu, X., Berg, A. A., Rowlandson, T., Pacheco, T., Mcnairn, H., Thibeault, M., , Martinez-fernandez, J., et al. (2017).

  Assessment of Version 4 of the SMAP Passive Soil Moisture

  . 2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), Fort Worth, TX, USA, 2017, 3941-3944.
• O'Neil, P., others, 3., Zreda, M. G., & others, 3. (2017). Assessment of Version 4 of the SMAP Passive Soil Moisture Standard Product. IEEE International Geoscience and Remote Sensing Symposium, 37, 4.
• Sarikaya, A., Ciner, A., Sen, E., Ersoy, O., & Zreda, M. G. (2017). Dating Young Lava Flows with Cosmogenic 36Cl: AN Example from the Late Pleistocene-Early Holocene ERCIYES Monogenetic Lava Domes in Central Turkey. EGU General Assembly Conference Abstracts, 19, 3937.
• Zreda, M. G., Montzka, C., Bogena, H., Monerris, A., Morrison, R., Muddu, S., & Vereecken, H. (2017). Validation of spaceborne and modelled surface soil moisture products with cosmic-ray neutron probes. Remote Sensing, 9(2), 103. doi:10.3390/rs9020103
• Andreasen, M., Bogena, H., Desilets, D., Jensen, K. H., Looms, M. C., & Zreda, M. (2016).

  Modeling cosmic ray neutron field measurements: MODELING COSMIC RAY NEUTRON FIELD MEASUREMENTS

  . Water Resources Research, 52(8), 6451-6471. doi:10.1002/2015wr018236
• Andreasen, M., Jensen, K. H., Desilets, D., Zreda, M., Bogena, H., & Looms, M. C. (2016). Can canopy interception and biomass be inferred from cosmic-ray neutron intensity? Results from neutron transport modeling. Hydrology and Earth System Science Discussions, 1-42. doi:doi:10.5194/hess-2016-226
• Andreasen, M., Jensen, K. H., Zreda, M., Desilets, D., Bogena, H., & Looms, M. C. (2016). Modeling cosmic ray neutron field measurements. WATER RESOURCES RESEARCH, 52(8), 6451-6471.
• Andreasen, M., Jensen, K. H., Zreda, M., Desilets, D., Bogena, H., & Looms, M. C. (2016). Modeling cosmic ray neutron field measurements. Water Resources Research, 52(8), 6451-6471.
• Baker, V. R., Bjornstad, B. N., Gaylord, D. R., Smith, G. A., Meyer, S. E., Alho, P., Breckenridge, R. M., Sweeney, M. R., & Zreda, M. (2016). Pleistocene megaflood landscapes of the Channeled Scabland. GSA Field Guides, 41, 1-73.
• Baker, V. R., Bjornstad, B. N., Smith, G. A., Meyer, S. E., Alho, P., Breckenridge, R. M., Sweeney, M. R., & Zreda, M. G. (2016). Pleistocene megaflood landscapes of the Channeled Scabland. GSA Field Guides, 41, 1-73.
• Basara, J. B., Cosh, M. H., Dong, J., Evett, S. R., Hatch, C. E., McKee, L., Ochsner, T. E., Sayde, C., Small, E. E., Steele-Dunne, S. C., & Zreda, M. (2016). The Soil Moisture Active Passive Marena, Oklahoma, In Situ Sensor Testbed (SMAP‐MOISST): Testbed Design and Evaluation of In Situ Sensors. Vadose Zone Journal, 15(4), 1-11. doi:10.2136/vzj2015.09.0122
• Chan, S. K., Bindlish, R., O'Neill, P. E., Njoku, E., Jackson, T., Colliander, A., Chen, F., Burgin, M., Dunbar, S., Piepmeier, J., Yueh, S., Entekhabi, D., Cosh, M. H., Caldwell, T., Walker, J., Wu, X., Berg, A., Rowlandson, T., Pacheco, A., , McNairn, H., et al. (2016). Assessment of the SMAP Passive Soil Moisture Product. IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, 54(8), 4994-5007.
• Chan, S. K., Bindlish, R., O'Neill, P., Njoku, E., Jackson, T., Colliander, A., Chen, F., Burgin, M., Dunbar, S., Piepmeier, J., Yueh, S., Entekhabi, D., Cosh, M. H., Caldwell, T., Walker, J., Wu, X., Berg, A., Rowlandson, T., Pacheco, A., , McNairn, H., et al. (2016). Assessment of the SMAP Passive Soil Moisture Product. IEEE Transactions on Geoscience and Remote Sensing, 54(8), 4994-5007.
• Chan, S. K., others, 2., Zreda, M., & others, t. (2016). Assessment of the SMAP Passive Soil Moisture Product. IEEE Transactions on Geoscience and Remote Sensing, 54(8), 4994-5007. doi:10.1109/TGRS.2016.2561938
• Chodyka, M., Grudniewski, T., Lubanska, Z., Nitychoruk, J., & Zreda, M. (2016).

  An innovative method of measuring soil moisture using cosmic-ray neutrons - three years of work of the sensor in southern Podlasie.

  . Journal of Civil Engineering, Environment and Architecture, 63(3), 51-58.
• Chodyka, M., Nitychoruk, J., Zreda, M., Grudniewski, T., & Lubanska, Z. (2016). Innowacyjna metoda pomiaru wilgotnosci gleby z zastosowaniem neutronow kosmicznych; trzy lata funkcjonowania czujnika na poludniowym Podlasiu [An innovative method of measuring soil moisture using cosmic-ray neutrons: three years of work of the sensor in southern Podlasie]. Czasopismo Inzynierii Ladowej, Srodowiska i Architektury [Journal of Civil Engineering, Environment and Architecture], 33(63), 51-58.
• Cosh, M. H., Ochsner, T. E., McKee, L., Dong, J., Basara, J. B., Evett, S. R., Hatch, C. E., Small, E. E., Steele-Dunne, S. C., Zreda, M., & Sayde, C. (2016). The Soil Moisture Active Passive Marena, Oklahoma, In Situ Sensor Testbed (SMAP-MOISST): Testbed Design and Evaluation of In Situ Sensors. VADOSE ZONE JOURNAL, 15(4).
• Cosh, M. H., Ochsner, T. E., McKee, L., Dong, J., Basara, J. B., Evett, S. R., Hatch, C. E., Small, E. E., Steele-Dunne, S. C., Zreda, M., & Sayde, C. (2016). The soil moisture active passive marena, Oklahoma, in situ sensor testbed (SMAP-MOISST): Testbed design and evaluation of in situ sensors. Vadose Zone Journal, 15(4).
• Cosh, M. H., Ochsner, T. E., McKee, L., Dong, J., Basara, J. S., Evett, S. R., Hatch, C. E., Small, E. E., Steele-Dunne, S. C., Zreda, M., & Sayde, C. (2016). The Soil Moisture Active Passive Marena, Oklahoma, In Situ Sensor Testbed (SMAP-MOISST): Testbed Design and Evaluation of In Situ Sensors. Vadose Zone Journal, 15. doi:10.2136/vzj2015.09.0122
• Phillips, F. M., Argento, D. C., Balco, G., Caffee, M. W., Clem, J., Dunai, T. J., Finkel, R., Goehring, B., Gosse, J. C., Hudson, A. M., Jull, A., Kelly, M. A., Kurz, M., Lal, D., Lifton, N., Marrero, S. M., Nishiizumi, K., Reedy, R. C., Schaefer, J., , Stone, J., et al. (2016). The CRONUS-Earth Project: A synthesis. QUATERNARY GEOCHRONOLOGY, 31, 119-154.
• Phillips, F. M., Argento, D. C., Balco, G., Caffee, M. W., Clem, J., Dunai, T. J., Finkel, R., Goehring, B., Gosse, J. C., Hudson, A. M., Jull, A., Kelly, M. A., Kurz, M., Lal, D., Lifton, N., Marrero, S. M., Nishiizumi, K., Reedy, R. C., Schaefer, J., , Stone, J., et al. (2016). The CRONUS-Earth Project: A synthesis. Quaternary Geochronology, 31, 119-154.
• Zreda, M. (2016). Land-surface hydrology with cosmic-ray neutrons: principles and applications. Journal of the Japanese Society of Soil Physics, 132(3), 25-30.
• Andreasen, M., Bogena, H., Desilets, D., Jensen, K. H., Looms, M. C., & Zreda, M. G. (2015).

  Determination of site specific calibration functions for the estimation of soil moisture from measurements of cosmic-ray neutron intensity

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• Dietrich, P., Köhli, M., Schmidt, U., Schrön, M., Zacharias, S., & Zreda, M. (2015).

  Footprint characteristics revised for field‐scale soil moisture monitoring with cosmic‐ray neutrons

  . Water Resources Research, 51(7), 5772-5790. doi:10.1002/2015wr017169
• Koehli, M., Schroen, M., Zreda, M., Schmidt, U., Dietrich, P., & Zacharias, S. (2015). Footprint characteristics revised for field-scale soil moisture monitoring with cosmic-ray neutrons. WATER RESOURCES RESEARCH, 51(7), 5772-5790.
• Köhli, M., Schrön, M., Schmidt, U., Dietrich, P., Zacharias, S., & Zreda, M. (2015). Footprint characteristics revised for field-scale soil moisture monitoring with cosmic-ray neutrons. Water Resources Research, 51, 5772-5790. doi:10.1002/2015WR017169
• Köhli, M., Schrön, M., Zreda, M., Schmidt, U., Dietrich, P., & Zacharias, S. (2015). Footprint characteristics revised for field-scale soil moisture monitoring with cosmic-ray neutrons. Water Resources Research, 51(7), 5772-5790.
• Sarikaya, M. A., Ciner, A., & Zreda, M. (2015). Fairy chimney erosion rates on Cappadocia ignimbrites, Turkey: Insights from cosmogenic nuclides. GEOMORPHOLOGY, 234, 182-191.
• Sarikaya, M. A., Çiner, A., & Zreda, M. (2015). Fairy chimney erosion rates on Cappadocia ignimbrites, Turkey: Insights from cosmogenic nuclides. Geomorphology, 234, 182-191.
• Sarikaya, M., Çiner, A., & Zreda, M. G. (2015). Fairy chimney erosion rates on Cappadocia ignimbrites, Turkey: Insights from cosmogenic nuclides. Geomorphology, 234, 182-191.
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  M.A. Sarikaya - former PhD student of Zreda at UA. Paper describes work done while at UA.
• Zreda, M. G., Nitychoruk, J., Chodyka, M., Swierczewska-Pietras, K., & Zbucki, L. (2015). Nowa metoda pomiaru wilgotnooeci gleby z wykorzystaniem neutronów kosmogenicznych. Przeglad Geologiczny [Geological Review], 63, 239-246.
• Zreda, M., Nitychoruk, J., Chodyka, M., ͆wierczewska-Pietras, K., & Zbucki, Ł. (2015). New method for measuring soil moisture using cosmogenic neutrons [Nowa metoda pomiaru wilgotnos̈ci gleby z wykorzystaniem neutronów kosmogenicznych]. Przeglad Geologiczny, 63(4), 239-246.
• Desilets, D., & Zreda, M. (2014). Cosmic-ray hydrometeorology. Encyclopedia of Earth Sciences Series, 83-86.
• Dong, J., Ochsner, T. E., Zreda, M. G., Cosh, M. H., & Zou, C. B. (2014). Calibration and validation of the COSMOS rover for surface soil moisture measurement. Vadose Zone Journal, 13(4).
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  Research paper on mapping soil moisture.
• Dong, J., Ochsner, T. E., Zreda, M., Cosh, M. H., & Zou, C. B. (2014). Calibration and Validation of the COSMOS Rover for Surface Soil Moisture Measurement. VADOSE ZONE JOURNAL, 13(4).
• Dong, J., Ochsner, T. E., Zreda, M., Cosh, M. H., & Zou, C. B. (2014). Calibration and validation of the COSMOS rover for surface soil moisture measurement. Vadose Zone Journal, 13(4).
• Makos, M., Dzierzek, J., Nitychoruk, J., & Zreda, M. (2014). Timing of glacier advances and climate in the High Tatra Mountains (Western Carpathians) during the Last Glacial Maximum. QUATERNARY RESEARCH, 82(1), 1-13.
• Makos, M., Dzierzek, J., Nitychoruk, J., & Zreda, M. (2014). Timing of glacier advances and climate in the High Tatra Mountains (Western Carpathians) during the Last Glacial Maximum. Quaternary Research (United States), 82(1), 1-13.
• Makos, M., Dzierzek, J., Nitychoruk, J., & Zreda, M. (2014). Timing of glacier advances and climate in the High Tatra Mountains (Western Carpathians) during the Last Glacial Maximum. Quaternary Research, 82, 1-13.
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  Research paper on glaciations in Poland.
• Sarikaya, M. A., Ciner, A., Haybat, H., & Zreda, M. (2014). An early advance of glaciers on Mount Akdag, SW Turkey, before the global Last Glacial Maximum; insights from cosmogenic nuclides and glacier modeling. QUATERNARY SCIENCE REVIEWS, 88, 96-109.
• Sarikaya, M. A., Ciner, A., Haybat, H., & Zreda, M. (2014). An early advance of glaciers on Mount Akdag, SW Turkey, before the global Last Glacial Maximum; insights from cosmogenic nuclides and glacier modeling. Quaternary Science Reviews, 88, 96-109.
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  Research paper on glaciations in Turkey.
• Sarikaya, M. A., Çiner, A., Haybat, H., & Zreda, M. (2014). An early advance of glaciers on Mount Akdaǧ, SW Turkey, before the global Last Glacial Maximum; insights from cosmogenic nuclides and glacier modeling. Quaternary Science Reviews, 88, 96-109.
• Adams, H., Franz, T. E., Hornbuckle, B. K., Irvin, S. L., Kolb, T. E., Rosolem, R., Shuttleworth, W. J., Zreda, M., & Zweck, C. (2013).

  Ecosystem-scale measurements of biomass water using cosmic ray neutrons: ECOSYSTEM MEASUREMENTS OF BIOMASS WATER

  . Geophysical Research Letters, 40(15), 3929-3933. doi:10.1002/grl.50791
• Chrisman, B., & Zreda, M. (2013). Quantifying mesoscale soil moisture with the cosmic-ray rover. Hydrology and Earth System Sciences, 17(12), 5097-5108.
• Desilets, D., & Zreda, M. (2013).

  Footprint diameter for a cosmic-ray soil moisture probe: Theory and Monte Carlo simulations: Footprint Diameter for a Cosmic-Ray Soil Moisture Probe

  . Water Resources Research, 49(6), 3566-3575. doi:10.1002/wrcr.20187
• Desilets, D., & Zreda, M. (2013). Footprint diameter for a cosmic-ray soil moisture probe: Theory and Monte Carlo simulations. WATER RESOURCES RESEARCH, 49(6), 3566-3575.
• Desilets, D., & Zreda, M. (2013). Footprint diameter for a cosmic-ray soil moisture probe: Theory and Monte Carlo simulations. Water Resources Research, 49(6), 3566-3575.
• Dzierzek, J., Nitychoruk, J., Zreda, M., & Zreda-gostynska, G. (2013).

  Cosmogenic isotope 36CI - a new perspective for Quaternary chronostratigraphy of Poland

  . Geological Quarterly, 40(3), 481-486.
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  The new method of absolute dating by (cosmogenic isotope 36 Cl) is considered. The method is based on measuring concentrations of isotope 36 Cl which is produced in terrestrial rocks exposed at the surface to cosmic radiation. The presence of 36 Cl in most of the rocks and its long half-life make it useful in determination of the age of landforms and sediments in different depositional environments within the time range from a few thousand years to about one million years. The initial samples collected in the Polish Tatra Mts. are being analyzed in the U.S.A. The authors believe that cosmogenic 36 Cl method becomes a new important tool in Quaternary chronostratigraphy of Poland.
• Franz, T. E., Kurc, S. A., Rosolem, R., Shuttleworth, W. J., Zeng, X., & Zreda, M. (2013). The Effect of Atmospheric Water Vapor on Neutron Count in the Cosmic-Ray Soil Moisture Observing System. Journal of Hydrometeorology, 14(5), 1659-1671. doi:10.1175/jhm-d-12-0120.1
• Franz, T. E., Zreda, M., Ferre, T., & Rosolem, R. (2013). An assessment of the effect of horizontal soil moisture heterogeneity on the area-average measurement of cosmic-ray neutrons. Water Resources Research, 49(10), 6450-6458.
• Franz, T. E., Zreda, M., Rosolem, R., & Ferre, T. (2013). A universal calibration function for determination of soil moisture with cosmic-ray neutrons. Hydrology and Earth System Sciences, 17(2), 453-460.
• Franz, T. E., Zreda, M., Rosolem, R., Hornbuckle, B. K., Irvin, S. L., Adams, H., Kolb, T. E., Zweck, C., & Shuttleworth, W. J. (2013). Ecosystem-scale measurements of biomass water using cosmic ray neutrons. GEOPHYSICAL RESEARCH LETTERS, 40(15), 3929-3933.
• Franz, T. E., Zreda, M., Rosolem, R., Hornbuckle, B. K., Irvin, S. L., Adams, H., Kolb, T. E., Zweck, C., & Shuttleworth, W. J. (2013). Ecosystem-scale measurements of biomass water using cosmic ray neutrons. Geophysical Research Letters, 40(15), 3929-3933.
• Makos, M., Nitychoruk, J., & Zreda, M. (2013). Deglaciation chronology and paleoclimate of the Pieciu Stawow Polskich/Roztoki Valley, high Tatra Mountains, Western Carpathians, since the Last Glacial Maximum, inferred from Cl-36 exposure dating and glacier-climate modelling. QUATERNARY INTERNATIONAL, 293, 63-78.
• Makos, M., Nitychoruk, J., & Zreda, M. (2013). Deglaciation chronology and paleoclimate of the Pieogonekciu Stawów Polskich/Roztoki Valley, high Tatra Mountains, Western Carpathians, since the Last Glacial Maximum, inferred from 36Cl exposure dating and glacier-climate modelling. Quaternary International, 293, 63-78.
• Makos, M., Nitychoruk, J., & Zreda, M. (2013). Deglaciation chronology and paleoclimate of the Pie{ogonek}ciu Stawów Polskich/Roztoki Valley, high Tatra Mountains, Western Carpathians, since the Last Glacial Maximum, inferred from ³⁶Cl exposure dating and glacier-climate modelling. Quaternary International, 293, 63-78.
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  Abstract: Exposure dating of abraded bedrock surfaces below glacial trimlines in the Pie{ogonek}ciu Stawów Polskich/Roztoki Valley, using cosmogenic 36Cl, has been applied to determine the deglaciation chronology in the study area. Nineteen rock samples yielded ages between 21.5 and 9.5ka. The spatial distribution of ages provides evidence of progressive downwasting of glaciers within the study area. Dates of exposure indicate that the onset of ice volume decrease occurred no later than 21.5ka. This provides evidence that the local maximum glaciation occurred in accordance with the global Last Glacial Maximum (LGM). The first period of deglaciation in the study area was completed around 18ka. Further significant loss of ice volume is confirmed between 15 and 13ka. The spatial distribution of chronological data within the Pie{ogonek}ciu Stawów Polskich Valley indicates post-LGM readvances of glaciers around 17ka and 12ka. Using the glacier modelling and paleoclimate proxies from the study area, the early Late Glacial glacier had been stable with a 9-10°C decrease in temperature and 30-50% lower precipitation in relation to modern conditions. The subsequent advance took place with temperatures 6-7°C lower and 10-30% less precipitation. The timing of the readvances is nearly synchronous with Late Glacial advances in the European Alps, Southern Carpathians and Anatolian peninsula. This suggests synchronicity of major climatic fluctuations across Central Europe and the northern margin of the Mediterranean Basin. © 2012 Elsevier Ltd and INQUA.
• Makos, M., Nitychoruk, J., & Zreda, M. (2013). The Younger Dryas climatic conditions in the Za Mnichem Valley (Polish High Tatra Mountains) based on exposure-age dating and glacier-climate modelling. BOREAS, 42(3), 745-761.
• Makos, M., Nitychoruk, J., & Zreda, M. (2013). The Younger Dryas climatic conditions in the Za Mnichem Valley (Polish High Tatra Mountains) based on exposure-age dating and glacier-climate modelling. Boreas, 42(3), 745-761.
• Ochsner, T. E., Cosh, M. H., Cuenca, R. H., Dorigo, W. A., Draper, C. S., Hagimoto, Y., Kerr, Y. H., Larson, K. M., Njoku, E. G., Small, E. E., & Zreda, M. (2013). State of the Art in Large-Scale Soil Moisture Monitoring. SOIL SCIENCE SOCIETY OF AMERICA JOURNAL, 77(6), 1888-1919.
• Ochsner, T. E., Cosh, M. H., Cuenca, R. H., Dorigo, W. A., Draper, C. S., Hagimoto, Y., Kerr, Y. H., Larson, K. M., Njoku, E. G., Small, E. E., & Zreda, M. (2013). State of the art in large-scale soil moisture monitoring. Soil Science Society of America Journal, 77(6), 1888-1919.
• Rosolem, R., Shuttleworth, W. J., Zreda, M., Franz, T. E., Zeng, X., & Kurc, S. A. (2013). The Effect of Atmospheric Water Vapor on Neutron Count in the Cosmic-Ray Soil Moisture Observing System. JOURNAL OF HYDROMETEOROLOGY, 14(5), 1659-1671.
• Rosolem, R., Shuttleworth, W. J., Zreda, M., Franz, T. E., Zeng, X., & Kurc, S. A. (2013). The effect of atmospheric water vapor on neutron count in the cosmic-ray soil moisture observing system. Journal of Hydrometeorology, 14(5), 1659-1671.
• Shuttleworth, J., Rosolem, R., Zreda, M., & Franz, T. (2013). The COsmic-ray Soil Moisture Interaction Code (COSMIC) for use in data assimilation. Hydrology and Earth System Sciences, 17(8), 3205-3217.
• Stillman, S., Zeng, X., Shuttleworth, W. J., Goodrich, D. C., Unkrich, C. L., & Zreda, M. (2013). Spatiotemporal Variability of Summer Precipitation in Southeastern Arizona. JOURNAL OF HYDROMETEOROLOGY, 14(6), 1944-1951.
• Stillman, S., Zeng, X., Shuttleworth, W. J., Goodrich, D. C., Unkrich, C. L., & Zreda, M. (2013). Spatiotemporal variability of summer precipitation in southeastern arizona. Journal of Hydrometeorology, 14(6), 1944-1951.
• Zreda, M., Shuttleworth, W. J., Zeng, X., Zweck, C., Desilets, D., Franz, T., & Rosolem, R. (2013). COSMOS: the COsmic-ray Soil Moisture Observing System (vol 16, pg 4079, 2012). HYDROLOGY AND EARTH SYSTEM SCIENCES, 17(3), 1065-1066.
• Zreda, M., Shuttleworth, W. J., Zeng, X., Zweck, C., Desilets, D., Franz, T., & Rosolem, R. (2013). Erratum: cOSMOS: The COsmic-ray soil moisture observing system (Hydrology and Earth System Sciences (2012) 16 (4079-4099)). Hydrology and Earth System Sciences, 17(3), 1065-1066.
• Zweck, C., Zreda, M., & Desilets, D. (2013). Snow shielding factors for cosmogenic nuclide dating inferred from Monte Carlo neutron transport simulations. EARTH AND PLANETARY SCIENCE LETTERS, 379, 64-71.
• Zweck, C., Zreda, M., & Desilets, D. (2013). Snow shielding factors for cosmogenic nuclide dating inferred from Monte Carlo neutron transport simulations. Earth and Planetary Science Letters, 379, 64-71.
• Franz, T. E., Zreda, M., Ferre, T., Rosolem, R., Zweck, C., Stillman, S., Zeng, X., & Shuttleworth, W. J. (2012). Measurement depth of the cosmic ray soil moisture probe affected by hydrogen from various sources. WATER RESOURCES RESEARCH, 48.
• Franz, T. E., Zreda, M., Ferre, T., Rosolem, R., Zweck, C., Stillman, S., Zeng, X., & Shuttleworth, W. J. (2012). Measurement depth of the cosmic ray soil moisture probe affected by hydrogen from various sources. Water Resources Research, 48(8).
• Franz, T. E., Zreda, M., Rosolem, R., & Ferre, T. (2012). Field Validation of a Cosmic-Ray Neutron Sensor Using a Distributed Sensor Network. VADOSE ZONE JOURNAL, 11(4).
• Franz, T. E., Zreda, M., Rosolem, R., & Ferre, T. (2012). Field validation of a cosmic-ray neutron sensor using a distributed sensor network. Vadose Zone Journal, 11(4).
• Makos, M., Nitychoruk, J., & Zreda, M. (2012). The Younger Dryas climatic conditions in the Za Mnichem Valley (Polish High Tatra Mountains) based on exposure-age dating and glacier-climate modelling: The Younger Dryas climatic conditions, Polish High Tatra Mountains. Boreas, 42(3), 745-761. doi:10.1111/j.1502-3885.2012.00298.x
• Phillips, F., Zreda, M., Flinsch, M., Elmore, D., & Sharma, P. (2012). A reevaluation of cosmogenic Cl-36 production rates in terrestrial rocks. GEOPHYSICAL RESEARCH LETTERS, 23(9), 949-952.
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  We have measured Cl-36 in a suite of 33 rock samples having well-constrained exposure histories and ages. The Cl-36 production parameters were estimated by minimizing the squared deviations between the Cl-36 and independent ages, yielding the following production parameters: spallation and muon production from Ca 2940+/-200 atoms Cl-36 (mole Ca)(-1) yr(-1), spallation from K 6020+/-400 atoms Cl-36 (mole K)(-1) yr(-1), and neutron production in air 586+/-40 fast neutrons (g air)(-1) yr(-1). The new production constants for spallation on Ca and thermal neutron activation are in good agreement with previous results, but that for spallation on K is about 50% larger.
• Walker, J. P., Dumedah, G., Monerris, A., Gao, Y., Rüdiger, C., Wu, X., Panciera, R., Merlin, O., Pipunic, R., Ryu, D., & Zreda, M. (2012). High resolution soil moisture mapping. Digital Soil Assessments and Beyond - Proceedings of the Fifth Global Workshop on Digital Soil Mapping, 45-51.
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  Abstract: Soil moisture information is of critical importance to real-world applications such as agriculture, water resource management, flood, fire and landslide prediction, mobility, soil hydraulic parameter estimation etc. Many of these applications require soil moisture information at high resolution. While this may be estimated from land surface models, the predictions are often poor due to inadequate model physics, poor parameter estimates and erroneous atmospheric forcing data. An alternative is remote sensing but most techniques only give a soil moisture estimate for the top few centimetres. Moreover, the sensors that give the most reliable soil moisture estimates (passive microwave) have relatively low spatial resolution from space, being on the order of 50 km. Such sensors include the European Space Agency (ESA) Soil Moisture and Ocean Salinity (SMOS) mission launched in Nov 2009, and the National Aeronautics and Space Administration (NASA) Soil Moisture Active Passive (SMAP) mission scheduled for launch in Oct 2014. Other high spatial resolution satellite observations such as active microwave, visible and thermal have been shown to contain information on soil moisture, but their data is noisy and/or difficult to interpret. However, it is expected that the low resolution passive microwave data may be downscaled using the noisy high resolution data and/or modeling. For example, SMAP will provide a better than 10 km resolution soil moisture product by merging 3 km active microwave data with 40 km passive microwave data. This paper presents some examples of high resolution soil moisture mapping from ground and airborne techniques, combined active-passive satellite soil moisture retrieval, optical downscaling, and assimilation into a high resolution land surface model. © 2012 Taylor & Francis Group.
• Zreda, M., Ciner, A., Sarikaya, M. A., Zweck, C., & Bayari, S. (2012). Remarkably extensive glaciation and fast deglaciation and climate change in Turkey near the Pleistocene-Holocene boundary (vol 39, pg 1051, 2011). GEOLOGY, 40(1), 70-70.
• Zreda, M., Shuttleworth, W. J., Zeng, X., Zweck, C., Desilets, D., Franz, T., & Rosolem, R. (2012). COSMOS: The cosmic-ray soil moisture observing system. Hydrology and Earth System Sciences, 16(11), 4079-4099.
• Zweck, C., Zreda, M., Anderson, K. M., & Bradley, E. (2012). The theoretical basis of ACE, an Age Calculation Engine for cosmogenic nuclides. CHEMICAL GEOLOGY, 291, 199-205.
• Zweck, C., Zreda, M., Anderson, K. M., & Bradley, E. (2012). The theoretical basis of ACE, an Age Calculation Engine for cosmogenic nuclides. Chemical Geology, 291, 199-205.
• Sarikaya, M. A., Çiner, A., & Zreda, M. (2011). Quaternary glaciations of Turkey. Developments in Quaternary Science, 15, 393-403.
• Zreda, M., Ciner, A., Sarikaya, M. A., Zweck, C., & Bayari, S. (2011). Remarkably extensive glaciation and fast deglaciation and climate change in Turkey near the Pleistocene-Holocene boundary. GEOLOGY, 39(11), 1051-1054.
• Zreda, M., Çiner, A., Sarikaya, M. A., Zweck, C., & Bayari, S. (2011). Remarkably extensive glaciation and fast deglaciation and climate change in Turkey near the Pleistocene-Holocene boundary. Geology, 39(11), 1051-1054.
• Desilets, D., Ferré, T. P., & Zreda, M. (2010).

  Nature's neutron probe: Land surface hydrology at an elusive scale with cosmic rays: NATURE'S NEUTRON PROBE

  . Water Resources Research, 46(11). doi:10.1029/2009wr008726
• Desilets, D., Zreda, M., & Ferré, T. (2010). Nature's neutron probe: Land surface hydrology at an elusive scale with cosmic rays. Water Resources Research, 46(11).
• Rassbach, L., Anderson, K., Bradley, L., Zweck, C., & Zreda, M. (2010). End-to-End Support for Dating Paleolandforms. ADVANCES IN INTELLIGENT DATA ANALYSIS IX, PROCEEDINGS, 6065, 171-+.
• Rassbach, L., Anderson, K., Bradley, L., Zweck, C., & Zreda, M. (2010). End-to-end support for dating paleolandforms. Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), 6065 LNCS, 171-183.
• Shanahan, T., & Zreda, M. (2010). Chronology of quaternary glaciations in East Africa. EARTH AND PLANETARY SCIENCE LETTERS, 177(1-2), 23-42.
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  A new glacial chronology for equatorial East Africa is developed using in situ cosmogenic Cl-36 measured in 122 boulders from moraines on Mount Kenya and Kilimanjaro. The oldest deposits sampled on Kilimanjaro yield a limiting Cl-36 age of > 360 calendar kyr (all Cl-36 ages are in calendar years, cal. kyr or cal. yr). On Mount Kenya, the oldest moraines give ages of 355-420 kyr (Liki I) and 255-285 kyr (Teleki). Given the uncertainty in our Cl-36 ages, the Liki I moraine may correspond to either marine isotope stage 10 or 12, whereas the Teleki moraine correlates with stage 8. There is no evidence for stage 6 on either mountain. The Liki II moraines on Mt. Kenya and moraines of the Fourth Glaciation on Kilimanjaro give ages of 28 +/- 3 kyr and 20 +/- 1 kyr, respectively. They represent the last glacial maximum (LGM) and correlate with stage 1 of the marine isotope record. A series of smaller moraines above the LGM deposits record several readvances that occurred during the late glacial. On Mt. Kenya, these deposits date to 14.6 +/- 1.2 kyr (Liki IIA), 10.2 +/- 0.5 kyr (Liki III), 8.6 +/- 0.2 kyr (Liki IIIA) and similar to 200 yr (Lewis); the corresponding deposits on Kilimanjaro have mean ages of 17.3 +/- 2.9 kyr (Fourth Glaciation-Saddle), 15.8 +/- 2.5 kyr (Little Glaciation-Saddle), and 13.8 +/- 2.3 kyr (Fourth Glaciation Kibo). These data indicate that the climate of the tropics was extremely variable at the end of the last glacial cycle. (C) 2000 Elsevier Science B.V. All rights reserved.
• Clark, D. H., Elmore, D., Phillips, F. M., Plummer, M. A., & Zreda, M. (2009).

  Glacial geology and chronology of Bishop Creek and vicinity, eastern Sierra Nevada, California

  . GSA Bulletin, 121(7-8), 1013-1033. doi:10.1130/b26271.1
• Keszthelyi, L. P., Baker, V. R., Jaeger, W. L., Gaylord, D. R., Bjornstad, B. N., Greenbaum, N., Self, S., Thordarson, T., Porat, N., & Zreda, M. G. (2009). Floods of water and lava in the Columbia River Basin: Analogs for Mars. GSA Field Guides, 15, 845-874.
• Phillips, F. M., Zreda, M., Plummer, M. A., Elmore, D., & Clark, D. H. (2009). Glacial geology and chronology of Bishop Creek and vicinity, eastern Sierra Nevada, California. Bulletin of the Geological Society of America, 121(7-8), 1013-1033.
• Phillips, F. M., Zreda, M., Plummer, M. A., Elmore, D., & Clark, D. H. (2009). Glacial geology and chronology of Bishop Creek and vicinity, eastern Sierra Nevada, California. GEOLOGICAL SOCIETY OF AMERICA BULLETIN, 121(7-8), 1013-1033.
• Sarikaya, M. A., Zreda, M., & Çiner, A. (2009). Glaciations and paleoclimate of Mount Erciyes, central Turkey, since the Last Glacial Maximum, inferred from 36Cl cosmogenic dating and glacier modeling. Quaternary Science Reviews, 28(23-24), 2326-2341.
• Sarikaya, M. A., Zreda, M., Ciner, A., & Zweck, C. (2009). Cold and wet Last Glacial Maximum on Mount Sandiras, SW Turkey, inferred from cosmogenic dating and glacier modeling. QUATERNARY SCIENCE REVIEWS, 27(7-8), 769-780.
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  In situ cosmogenic (36)Cl was measured in boulders from moraines on Mount Sandiras (37.1 degrees N, 28.8 degrees E, 2295 m), the southwestern most previously glaciated mountain in Turkey. Valleys on the north side of the mountain were filled with 1.5 km long glaciers that terminated at an altitude of 1900 m. The glacial activity on Mount Sandiras correlates with the broadly defined Last Glacial Maximum (LGM). The maximum glaciation occurred approximately 20.4 +/- 1.3 ka (I sigma; 1 ka = 1000 calendar years) ago, when glaciers started retreating and the most extensive moraines were deposited. The glaciers readvanced and retreated by 19.6 +/- 1.6 ka ago, and then again by 16.2 +/- 0.5 ka. Using the glacier modeling and the palcoclimate proxies from the Eastern Mediterranean, we estimated that if temperatures during LGM were 8.5-11.5 degrees C lower than modern, precipitation was up to 1.9 times more than that of today. Thus, the local LGM climate was cold and wet which is at odds with the conventional view of the LGM as being cold and dry in the region. (C) 2008 Elsevier Ltd. All rights reserved.
• Davis, S., Cecil, L., Zreda, M., & Moysey, S. (2008). Chlorine-36, bromide, and the origin of spring water. CHEMICAL GEOLOGY, 179(1-4), 3-16.
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  Natural ratios of chlorine-36 (Cl-36) to stable chlorine (i.e.. Cl-36/Cl X 10(-15)) vary in shallow groundwater of the United States from about 50 in coastal areas to about 1400 in the northern Rocky Mountains. Ratios lower than these indicate the presence of chloride (Cl-) that has been isolated from the atmosphere for hundreds of thousands of years, if not longer. Higher ratios, which can exceed 5000, usually originate from fallout from testing thermonuclear devices in the western Pacific in the 1950s.
• Pigati, J. S., Zreda, M., Zweck, C., Almasi, P. F., Elmore, D., & Sharp, W. D. (2008). Ages and inferred causes of Late Pleistocene glaciations on Mauna Kea, Hawai'i. JOURNAL OF QUATERNARY SCIENCE, 23(6-7), 683-702.
• Sarikaya, M. A., Zreda, M., Çiner, A., & Zweck, C. (2008). Cold and wet Last Glacial Maximum on Mount Sandidotlessras, SW Turkey, inferred from cosmogenic dating and glacier modeling. Quaternary Science Reviews, 27(7-8), 769-780.
• ZREDA, M., PHILLIPS, F., KUBIK, P., SHARMA, P., & ELMORE, D. (2008). COSMOGENIC CL-36 DATING OF A YOUNG BASALTIC ERUPTION COMPLEX, LATHROP WELLS, NEVADA. GEOLOGY, 21(1), 57-60.
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  It has been proposed that the Lathrop Wells volcanic center, a late Quaternary basaltic complex in southern Nevada, has erupted more than once. In common with most Quaternary basalts, this volcanic center has proved difficult to date by K/Ar and other commonly employed methods. We have measured the accumulation of Cl-36 in 11 samples from lava flows and volcanic bombs and obtained a combined average age of 81 +/- 7.9 ka, with no systematic differences between sample subsets collected from different volcanic features. The Cl-36 dates do not support a history of multiple eruptions, but neither do they completely preclude the possibility.
• Zreda, M., Desilets, D., Ferré, T., & Scott, R. L. (2008). Measuring soil moisture content non-invasively at intermediate spatial scale using cosmic-ray neutrons. Geophysical Research Letters, 35(21).
• Zweck, C., & Zreda, A. (2008). The theoretical basis for ACE, an age calculation engine for cosmogenic nuclides. GEOCHIMICA ET COSMOCHIMICA ACTA, 72(12), A1108-A1108.
• Desilets, D., Zreda, M., & Ferré, T. (2007). Scientist water equivalent measured with cosmic rays at 2006 AGU fall meeting. Eos, 88(48), 521-522.
• Dzierzek, J., & Zreda, M. (2007). Timing and style of deglaciation of Northeastern Poland from cosmogenie Cl-36 dating of glacial and glaciofluvial deposits. GEOLOGICAL QUARTERLY, 51(2), 203-216.
• Dzierzek, J., & Zreda, M. (2007). Timing and style of deglaciation of northeastern Poland from cosmogenic 36Cl dating of glacial and glaciofluvial deposits. Geological Quarterly, 51(2), 203-216.
• Szwed-Kolinska, M., Kurylak, A., Budnik-Szymoniuk, M., Zreda, A., & Piasecka, E. (2007). Discharge home-happiness or anxiety?. EUROPEAN JOURNAL OF ONCOLOGY NURSING, 11(2), 193-193.
• Desilets, D., & Zreda, M. (2006). Elevation dependence of cosmogenic 36Cl production in Hawaiian lava flows. Earth and Planetary Science Letters, 246(3-4), 277-287.
• Desilets, D., & Zreda, M. (2006). Elevation dependence of cosmogenic ³⁶Cl production in Hawaiian lava flows. Earth and Planetary Science Letters, 246(3-4), 277-287.
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  Abstract: We measured an elevation profile of cosmogenic 36Cl in two well-preserved lava flows on Mauna Kea, Hawaii (19.8° N, 155.5° W) in order to directly constrain the elevation dependence of cosmogenic nuclide production rates. The flows are vertically-extensive hawaiites erupted at 40.1 ± 0.6 and 62.2 ± 1.0 ka from point-vents on the upper flanks of Mauna Kea. The average paleo cutoff rigidity (a measure of geomagnetic shielding of cosmic rays) for these flows is 11 GV and their paleo-elevation range is 2100-3700 m. Production of 36Cl is dominated by neutron reactions, with the high-energy 39K(n,x) and 40Ca(n,x) mechanisms accounting for nearly half of the 36Cl production and the low-energy reaction 35Cl(n,γ) responsible for the remaining half. Production by negative muons is small at the elevations of our samples, accounting for less than 2% of the total production in the lowest elevation samples. The elevation dependence of 36Cl production measured in these lava flows is described by an effective attenuation length of 138 ± 5 g cm- 2. This result is close to the value of 140 g cm- 2 determined from neutron monitor surveys of high-energy nucleon fluxes, but significantly below the value of 149 g cm- 2 determined from measurements of low-energy neutrons. The predicted atmospheric attenuation length for these lava flows, incorporating both high- and low-energy mechanisms, is 144 g cm- 2. The good agreement between the 36Cl elevation profile and cosmic-ray surveys validates the use of neutron flux measurements to scale 36Cl production rates when production by muons is negligible. © 2006 Elsevier B.V. All rights reserved.
• Desilets, D., & Zreda, M. (2006). Elevation dependence of cosmogenic Cl-36 production in Hawaiian lava flows. EARTH AND PLANETARY SCIENCE LETTERS, 246(3-4), 277-287.
• Desilets, D., Zreda, M., & Prabu, T. (2006). Extended scaling factors for in situ cosmogenic nuclides: New measurements at low latitude. Earth and Planetary Science Letters, 246(3-4), 265-276.
• Desilets, D., Zreda, M., Almasi, P. F., & Elmore, D. (2006). Determination of cosmogenic 36Cl in rocks by isotope dilution: innovations, validation and error propagation. Chemical Geology, 233(3-4), 185-195.
• ZREDA, M., PHILLIPS, F., ELMORE, D., KUBIK, P., SHARMA, P., & DORN, R. (2006). COSMOGENIC CL-36 PRODUCTION-RATES IN TERRESTRIAL ROCKS. EARTH AND PLANETARY SCIENCE LETTERS, 105(1-3), 94-109.
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  Chlorine-36 is produced in rocks exposed to cosmic rays at the earth surface through thermal neutron activation of Cl-35, spallation of K-39 and Ca-40, and slow negative muon capture by Ca-40. We have measured the Cl-36 content of C-14-dated glacial boulders from the White Mountains in eastern California and in a C-14-dated basalt flow from Utah. Effective, time-integrated production parameters were calculated by simultaneous solution of the Cl-36 production equations. The production rates due to spallation are 4160 +/- 310 and 3050 +/- 210 atoms Cl-36 yr-1 mol-1 K-39 and Ca-40, respectively. The thermal neutron capture rate was calculated to be (3.07 +/- 0.24) x 10(5) neutrons (kg of rock)-1 yr-1. The reported values are normalized to sea level and high geomagnetic latitudes. Production of Cl-36 at different altitudes and latitudes can be estimated by appropriate scaling of the sea level rates. Chlorine-36 dating was performed on carbonate ejecta from Meteor Crater, Arizona, and late Pleistocene morainal boulders from the Sierra Nevada, California. Calculated Cl-36 ages are in good agreement with previously reported ages obtained using independent methods.
• Desilets, D., & Zreda, M. (2005). Improving the accuracy and precision of scaling factors for in-situ cosmogenic geochronometers: New measurements of cosmic-ray neutrons in India and Hawaii. GEOCHIMICA ET COSMOCHIMICA ACTA, 69(10), A159-A159.
• Zreda, M., Desilets, D., Li, Y. H., Bradley, E., & Anderson, K. M. (2005). ICRONUS meets CRONUS-Earth: Improved calculations for cosmogenic dating methods - From neutron intensity to previously ignored correction factors. GEOCHIMICA ET COSMOCHIMICA ACTA, 69(10), A168-A168.
• England, J. H., Atkinson, N., Dyke, A. S., Evans, D., & Zreda, M. (2004). Late Wisconsinan buildup and wastage of the Innuitian Ice Sheet across southern Ellesmere Island, Nunavut. Canadian Journal of Earth Sciences, 41(1), 39-61.
• PHILLIPS, F., ZREDA, M., SMITH, S., ELMORE, D., KUBIK, P., & SHARMA, P. (2004). COSMOGENIC CHLORINE-36 CHRONOLOGY FOR GLACIAL DEPOSITS AT BLOODY CANYON, EASTERN SIERRA-NEVADA. SCIENCE, 248(4962), 1529-1532.
• Davis, S. N., Moysey, S., Cecil, L. D., & Zreda, M. (2003). Chlorine-36 in groundwater of the United States: Empirical data. Hydrogeology Journal, 11(2), 217-227.
• Davis, S. N., Moysey, S., Cecil, L. D., & Zreda, M. (2003). Chlorine-36 in groundwater of the United States: empirical data. HYDROGEOLOGY JOURNAL, 11(2), 217-227.
• Desilets, D., & Zreda, M. (2003). Spatial and temporal distribution of secondary cosmic-ray nucleon intensities and applications to in situ cosmogenic dating. Earth and Planetary Science Letters, 206(1-2), 21-42.
• Desilets, D., Zreda, M., & Ferre, T. P. (2003). Nature's neutron probe: Land surface hydrology at an elusive scale with cosmic rays. WATER RESOURCES RESEARCH, 46.
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  [1] Fast neutrons are generated naturally at the land surface by energetic cosmic rays. These "background" neutrons respond strongly to the presence of water at or near the land surface and represent a hitherto elusive intermediate spatial scale of observation that is ideal for land surface studies and modeling. Soil moisture, snow, and biomass each have a distinct influence on the spectrum, height profile, and directional intensity of neutron fluxes above the ground, suggesting that different sources of water at the land surface can be distinguished with neutron data alone. Measurements can be taken at fixed sites for long-term monitoring or in a moving vehicle for mapping over large areas. We anticipate applications in many previously problematic contexts, including saline environments, wetlands and peat bogs, rocky soils, the active layer of permafrost, and water and snow intercepted by vegetation, as well as calibration and validation of data from spaceborne sensors.
• Giaccio, B., Galadini, F., Sposato, A., Messina, P., Moro, M., Zreda, M., Cittadini, A., Salvi, S., & Todero, A. (2003). Image processing and roughness analysis of exposed bedrock fault planes as a tool for paleoseismological analysis: Results from the Campo Felice fault (Central Apennines, Italy). Geomorphology, 49(3-4), 281-301.
• Giaccio, B., Galadini, F., Sposato, A., Messina, P., Moro, M., Zreda, M., Cittadini, A., Salvi, S., & Todero, A. (2003). Image processing and roughness analysis of exposed bedrock fault planes as a tool for paleoseismological analysis: results from the Campo Felice fault (central Apennines, Italy). GEOMORPHOLOGY, 49(3-4), 281-301.
• Moysey, S., Davis, S. N., Zreda, M., & Cecil, L. D. (2003). The distribution of meteoric 36Cl/Cl in the United States: A comparison of models. Hydrogeology Journal, 11(6), 615-627.
• Moysey, S., Davis, S. N., Zreda, M., & Cecil, L. D. (2003). The distribution of meteoric Cl-36/Cl in the United States: a comparison of models. HYDROGEOLOGY JOURNAL, 11(6), 615-627.
• Sarikaya, M. A., Çiner, A., & Zreda, M. (2003). Late Quaternary glacial deposits of the Erciyes Volcano [Erciyes Volkani Geç Kuvaterner buzul çökelleri]. Yerbilimleri, 59-74.
• Sarikaya, M. A., Çiner, A., & Zreda, M. (2003). Late Quaternary glacial deposits of the Erciyes Volcano. Yerbilimleri, 59-74.
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  Abstract: Mount Erciyes, highest stratovolcano of Cappadocian Volcanic Province, witnessed widespread valley glaciations during Late Quaternary. It is characterized by four valleys and one ridge that contain a small glacier and glacial deposits on its flanks. Aksu Valley is a northwest trending U-shaped valley with an actual glacier descending down to 3400 m of elevation. Few dead ice fragments covered by debris are also present starting from the lower end of the glacier. Lateral and terminal moraines, together with young ablation moraines and outwash plains indicate three glacial epochs. The oldest and most extensive one is characterized by two well-preserved, 100 m high lateral moraines at altitudes 2900-2200 m. A vast outwash plain derived from these moraines contains large andesitic blocks up to 3-4 m in diameter. Another important glacial valley, situated on the eastarn side of the mountain, is Üçker Valley with a wide cirque area originated from a volcanic amphitheatre. It contains a vast terminal moraine complex covering the present ski area. On the southern rim of the mountain, several rock glaciers are also observed. Öksüzdere Valley is a northeast trending narrow glacial valley containing two lateral moraines between 2900-2300 m of altitude. Between these moraines, a younger hummocky moraine complex and an outwash plain are present. There is no glacial valley development on the southern side of the volcano. However, on the Topaktaş Ridge, small lateral and terminal moraines are present at altitudes between 3300 and 2500 m. Kirkpinar Valley, situated to the west of Aksu Valley, is covered by a northwest oriented small terminal moraine complex made up of lateral and hummocky moraines between 2850 and 2600 m of altitude. The data available on the modern glacier situated in the Aksu Valley, indicate that the recent glacier retreat probably started at least at the beginning of the 20th century.
• Sarikaya, M. A., Çiner, A., & Zreda, M. G. (2003). Erciyes Volkani Geç Kuvaterner buzul çökelleri. Yerbilimleri, 27(24), 59-74.
• Davis, S. N., Cecil, L. D., Zreda, M., & Moysey, S. (2001). Chlorine-36, bromide, and the origin of spring water. Chemical Geology, 179(1-4), 3-16.
• Desilets, D., & Zreda, M. (2001). On scaling cosmogenic nuclide production rates for altitude and latitude using cosmic-ray measurements. Earth and Planetary Science Letters, 193(1-2), 213-225.
• Desilets, D., Zreda, M., & Lifton, N. A. (2001). Comment on 'Scaling factors for production rates of in situ produced cosmogenic nuclides: a critical reevaluation' by Tibor J. Dunai. EARTH AND PLANETARY SCIENCE LETTERS, 188(1-2), 283-287.
• Desilets, D., Zreda, M., & Lifton, N. A. (2001). Comment on 'scalling factors for production rates of in situ produced cosmogenic nuclides: A critical reevaluation. Earth and Planetary Science Letters, 188(1-2), 283-287.
• Phillips, F., Zreda, M., Benson, L., Plummer, M., Elmore, D., & Sharma, P. (2001). Chronology for fluctuations in late Pleistocene Sierra Nevada glaciers and lakes. SCIENCE, 274(5288), 749-751.
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  Mountain glaciers, because of their small size, are usually close to equilibrium with the local climate and thus should provide a test of whether temperature oscillations in Greenland late in the last glacial period are part of global-scale climate variability or are restricted to the North Atlantic region. Correlation of cosmogenic chlorine-36 dates on Sierra Nevada moraines with a continuous radiocarbon-dated sediment record from nearby Owens Lake shows that Sierra Nevada glacial advances were associated with Heinrich events 5, 3, 2, and 1.
• Zreda, M., England, J., Phillips, F., Elmore, D., & Sharma, P. (2001). Unblocking of the Nares Strait by Greenland and Ellesmere ice-sheet retreat 10,000 years ago. NATURE, 398(6723), 139-142.
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  The extent of glaciation at the northern margin of the Canadian/Greenland high-latitude Arctic region over the past 30,000 years is uncertain. Geological arguments have been made for Greenland and Ellesmere Island ice sheets that coalesced to block the Nares Strait(1), and for restricted ice sheets on the two islands(2) leaving the strait open, as it is today(3). Distinguishing between these two possibilities would provide significant constraints on present understanding of the past circulation between the Arctic and Atlantic oceans(4,5), on estimates of past ice-volume(6), and on the response of the Greenland ice sheet to climate change(7). Radiocarbon analyses provide dates for the deglaciation of the islands' coasts, but do not yield information on whether ice filled the strait. Here we present measurements of cosmogenic Cl-36 that has accumulated in situ in erratics and glacially polished bedrock on islands within the Nares Strait. These data allow us to determine the time for which the rocks have been recently exposed to the atmosphere, and thus the age of the final deglaciation of the strait. We show that Greenland and Ellesmere ice sheets retreated from the Nares Strait about 10,000 years ago. The strait was filled with ice during the last glaciation, blocking this connection between the Arctic and Atlantic oceans, and supporting the model of extensive and long-lasting ice on land and sea in this regions(8-11).
• Cofaigh, C. O., England, J., & Zreda, M. (2000). Late Wisconsinan glaciation of southern Eureka Sound: evidence for extensive Innuitian Ice in the Canadian High Arctic during the Last Glacial Maximum. QUATERNARY SCIENCE REVIEWS, 19(13), 1319-1341.
• Cofaigh, C. Ó., England, J., & Zreda, M. (2000). Late Wisconsinan glaciation of southern Eureka Sound: Evidence for extensive Innuitian ice in the Canadian High Arctic during the Last Glacial Maximum. Quaternary Science Reviews, 19(13), 1319-1341.
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  Abstract: Southern Eureka Sound was originally proposed as the centre of an Innuitian Ice Sheet in the Canadian High Arctic at the Last Glacial Maximum (LGM) based largely on the pattern of Holocene emergence. This paper focuses on the glacial geological evidence for such an ice sheet in the region. Granite dispersal trains and ice-moulded bedrock record regional, westward flow of warm-based ice into Eureka Sound from SE Ellesmere Island. Regional ice was coalescent with local ice domes on inter-fiord peninsulas. Marine limit in the form of raised deltas, beaches and washing limits formed during deglaciation of the regional ice. Throughout southern Eureka Sound, marine limit dates ≤9.2 ka BP, indicating that ice commenced retreat during the early Holocene. Ice-divides were located along the highlands of central Ellesmere and Axel Heiberg islands, from which ice inundated Eureka Sound, flowing north and south along the channel. Regional radiocarbon dates on marine limit show that deglaciation occurred in two steps. Initial break-up and radial retreat of ice from Eureka Sound to the inner fiords was rapid and preceded stabilisation along adjacent coastlines and at fiord heads. Two-step deglaciation is also reflected in differences in glacial geomorphology between the inner and outer parts of many fiords. A prominent belt of fiord-head glaciogenic landforms, long proposed to mark the last glacial limit, is re-interpreted to record initial, stabilisation of ice margins due predominantly to bathymetric control. (C) 2000 Elsevier Science Ltd.
• Shanahan, T. M., & Zreda, M. (2000). Chronology of Quaternary glaciations in East Africa. Earth and Planetary Science Letters, 177(1-2), 23-42.
• Ó, C. C., England, J., & Zreda, M. (2000). Late Wisconsinan glaciation of southern Eureka Sound: Evidence for extensive Innuitian ice in the Canadian High Arctic during the Last Glacial Maximum. Quaternary Science Reviews, 19(13), 1319-1341.
• Dzierzek, J., Nitychoruk, J., Zreda-Gostyńska, G., & Zreda, M. (1999). The method of dating by cosmogenic 36Cl - New data in glacial chronology of the High Tatra Mts. [Metoda datowania kosmogenicznym izotopem 36Cl - Nowe dane do chronologii Glacjalnej Tatr Wysokich]. Przeglad Geologiczny, 47(11), 987-992.
• Dzierzek, J., Nitychoruk, J., Zreda-Gostyńska, G., & Zreda, M. (1999). The method of dating by cosmogenic ³⁶Cl - New data in glacial chronology of the High Tatra Mts.. Przeglad Geologiczny, 47(11), 987-992.
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  Abstract: The cosmogenic 36Cl method of dating of Quaternary deposits and the first results of dating of moraines in selected regions of the Polish Tatra Mts. are presented. The method is based on measuring the concentration of 36Cl that is produced and accumulated in rocks exposed to cosmic rays. The concentration of 36Cl in the rock depends on the production rate, decay constant and the time of exposure. Due to the long half-life of 36Cl (301,000 yr), the method can be used to determine ages of landforms and sediments in the age range from a few thousand to a few hundred thousand years. Thirty seven samples from glacial deposits and landforms have been dated and the results are presented in paleogeographical context. The obtained dates show that these glacial features are of Vistulian and Holocene age (21-6.5 ky). The oldest moraines (21-15.3 ky) are in the vicinity of Brzeziny, and the youngest (9.9-7.3 ka) are near Morskie Oko Lake. These results of 36Cl dating are an important contribution to the discussion of glacial chronology of this mountain range.
• Dzierzek, J., Nitychoruk, J., Zreda-gostynska, G., & Zreda, M. G. (1999).

  Metoda datowania kosmogenicznym izotopem 36Cl - nowe dane do chronologii glacjalnej Tatr Wysokich

  . Przegląd Geologiczny, 47(11), 987-992.
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  Prezentowana metoda polega na pomiarze zawartości izotopu 36Cl, powstalego w przypowierzchniowej warstwie skaly pod wplywem promieniowania kosmicznego. Przy określonym tempie produkcji ilośc akumulowanego w pobranej probce izotopu zalezy od czasu ekspozycji i stalej rozpadu. Dzieki dlugiemu czasowi polowicznego rozpadu (301000 lat) izotopem 36Cl mozna datowac formy powierzchni ziemi, powstale w przedziale wiekowym od kilku tysiecy do kilkuset tysiecy lat. Wyniki datowania 37 probek i form rzeźby lodowcowej w Tatrach metodą 36Cl zostaly przedstawione na szerszym tle paleogeograficznym. Otrzymano daty z przedzialu czasowego od 21 do 6,5 tysiecy lat. Wedlug dat „chlorowych” najstarsze są moreny w okolicach Brzezin (21–15,3 ka), a najmlodsze z okolic Morskiego Oka (9,9–7,3 ka). Wyniki datowania za pomocą 36Cl stanowią istotny glos w dyskusji nad chronologią glacjalną Tatr. THE METHOD OF DATING BY COSMOGENIC 36CL – NEW DATA IN GLACIAL CHRONOLOGY OF THE HIGH TATRA MTS. Summary The cosmogenic 36CI method of dating of Quaternary deposits and the first results of dating of moraines in selected regions of the Polish Tatra Mts. are presented. The method is based on measuring the concentration of 36CI that is produced and accumulated in rocks exposed to cosmic rays. The concentration of 36CI in the rock depends on the production rate, decay constant and the time of exposure. Due to the long half-life of 36CI (301,000 yr), the method can be used to determine ages of landforms and sediments in the age range from a few thousand to a few hundred thousand years. Thirty seven samples from glacial deposits and land forms have been dated and the results are presented in paleogeographical context. The obtained dates show that these glacial features are of Vistulian and Holocene age (21-6.5 ky). The oldest moraines (21-15.3 ky) are in the vicinity of Brzeziny, and the youngest (9.9-7.3 ka) are near Morskie Oko Lake. These results of 36Cl dating are an important contribution to the discussion of glacial chronology of this mountain range.
• Sarikaya, M. A., Zreda, M., & Ciner, A. (1999). Glaciations and paleoclimate of Mount Erciyes, central Turkey, since the Last Glacial Maximum, inferred from Cl-36 cosmogenic dating and glacier modeling. QUATERNARY SCIENCE REVIEWS, 28(23-24), 2326-2341.
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  Forty-four boulders from moraines in two glacial valleys of Mount Erciyes (38.53 degrees N, 35.45 degrees E, 3917 m), central Turkey, dated with cosmogenic chlorine-36 (Cl-36), indicate four periods of glacial activity in the past 22 ka (1 ka=1000 calendar years). Last Glacial Maximum (LGM) glaciers were the most extensive, reaching 6 km in length and descending to an altitude of 2150 m above sea level. These glaciers started retreating 21.3 +/- 0.9 ka (1 sigma) ago. They readvanced and retreated by 14.6 +/- 1.2 ka ago (Lateglacial), and again by 9.3 +/- 0.5 ka ago (Early Holocene). The latest advance took place 3.8 +/- 0.4 ka ago (Late Holocene). Using glacier modeling together with paleoclimate proxy data from the region, we reconstructed the paleoclimate at these four discrete times. The results show that LGM climate was 8-11 degrees C colder than today and moisture levels were somewhat similar to modern values, with a range between 20% more and 25% less than today. The analysis of Lateglacial advance suggests that the climate was colder by 4.5-6.4 degrees C based on up to 1.5 times wetter conditions. The Early Holocene was 2.1-4.9 degrees C colder and up to twice as wet as today, while the Late Holocene was 2.4-3 degrees C colder and its precipitation amounts approached to similar conditions as today. Our paleoclimate reconstructions show a general trend of warming for the last 22 ka, and an increase of moisture until Early Holocene, and a decrease after that time. The recent glacier terminates at 3450 m on the northwest side of the mountain. It is a remnant from the last advance (possibly during the Little Ice Age). Repeated measurements of glacier length between 1902 and 2008 reveal a retreat rate of 4.2 m per year, which corresponds to a warming rate of 0.9-1.2 degrees C per century. (c) 2009 Elsevier Ltd. All rights reserved.
• Zreda, M. (1999).

  Environmental Isotopes in Hydrogeology

  . Eos, Transactions American Geophysical Union, 80(19), 217-217. doi:10.1029/99eo00169
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  In the last 40 years, environmental isotopes have become almost indispensable tools in different branches of hydrology and related environmental disciplines. Their numerous applications in hydrogeology include tracing the sources of ground water, estimation of recharge rates, and determination of groundwater ages. Environmental isotopes have gained the position of prominence in hydrogeology because they can be routinely measured with high sensitivity, thus allowing for improved accuracy and precision in quantitative description of hydrogeological processes. Environmental Isotopes in Hydrogeology brings together the different isotopic techniques commonly used in hydrogeology and includes numerous examples and problem sets for students.
• Zreda, M., England, J., Phillips, F., Elmore, D., & Sharma, P. (1999). Unblocking of the Nares Strait by Greenland and Ellesmere ice-sheet retreat 10,000 years ago. Nature, 398(6723), 139-142.
• Bell, J. W., Brune, J. N., Liu, T., Zreda, M., & Yount, J. C. (1998).

  DATING PRECARIOUSLY BALANCED ROCKS IN SEISMICALLY ACTIVE PARTS OF CALIFORNIA AND NEVADA

  . Geology, 26(6), 495-498. doi:10.1130/0091-7613(1998)026<0495:dpbris>2.3.co;2
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  Precariously balanced boulders that could be knocked down by strong earthquake ground motion are found in some seismically active areas of southern California and Nevada. In this study we used two independent surface-exposure dating techniques—rock-varnish microlamination and cosmogenic 36 Cl dating methodologies—to estimate minimum- and maximum-limiting ages, respectively, of the precarious boulders and by inference the elapsed time since the sites were shaken down. The results of the exposure dating indicate that all of the precarious rocks are >10.5 ka and that some may be significantly older. At Victorville and Jacumba, California, these results show that the precarious rocks have not been knocked down for at least 10.5 k.y., a conclusion in apparent conflict with some commonly used probabilistic seismic hazard maps. At Yucca Mountain, Nevada, the ages of the precarious rocks are >10.5 to >27.0 ka, providing an independent measure of the minimum time elapsed since faulting occurred on the Solitario Canyon fault.
• Bell, J. W., Brune, J. N., Liu, T., Zreda, M., & Yount, J. C. (1998). Dating previously balanced rocks in seismically active parts of California and Nevada. Geology, 26(6), 495-498.
• Davis, S. N., Cecil, D., Zreda, M., & Sharma, P. (1998). Chlorine-36 and the initial value problem. HYDROGEOLOGY JOURNAL, 6(1), 104-114.
• Davis, S. N., Cecil, D., Zréda, M., & Sharma, P. (1998). Chlorine-36 and the initial value problem. Hydrogeology Journal, 6(1), 104-114.
• Desilets, D., Zreda, M., Almasi, P. F., & Elmore, D. (1998). Determination of cosmogenic Cl-36 in rocks by isotope dilution: innovations, validation and error propagation. CHEMICAL GEOLOGY, 233(3-4), 185-195.
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  Measurements of cosmogenic Cl-36 in terrestrial rocks provide quantitative information about exposure ages of landforms and surface features. The isotope dilution method for preparing Cl-36 samples is now widely used because it allows Cl-36 and Cl to be measured simultaneously on a single accelerator mass spectrometry target, increases the accuracy and precision of Cl determinations, and reduces rock sample size and laboratory work. In this paper we describe a new implementation of isotope dilution to Cl-36 dating, report experimental data verifying the accuracy of this approach, and show how errors in the measured stable isotope ratio propagate to errors in exposure ages.
• Zreda, M., & Noller, J. S. (1998). Ages of prehistoric earthquakes revealed by cosmogenic chlorine-36 in a bedrock fault scarp at Hebgen Lake. Science, 282(5391), 1097-1099.
• Zreda, M., Shuttleworth, W. J., Zeng, X., Zweck, C., Desilets, D., Franz, T. E., & Rosolem, R. (1998). COSMOS: the COsmic-ray Soil Moisture Observing System. HYDROLOGY AND EARTH SYSTEM SCIENCES, 16(11), 4079-4099.
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  The newly-developed cosmic-ray method for measuring area-average soil moisture at the hectometer horizontal scale is being implemented in the COsmic-ray Soil Moisture Observing System (or the COSMOS). The stationary cosmic-ray soil moisture probe measures the neutrons that are generated by cosmic rays within air and soil and other materials, moderated by mainly hydrogen atoms located primarily in soil water, and emitted to the atmosphere where they mix instantaneously at a scale of hundreds of meters and whose density is inversely correlated with soil moisture. The COSMOS has already deployed more than 50 of the eventual 500 cosmic-ray probes, distributed mainly in the USA, each generating a time series of average soil moisture over its horizontal footprint, with similar networks coming into existence around the world. This paper is written to serve a community need to better understand this novel method and the COSMOS project. We describe the cosmic-ray soil moisture measurement method, the instrument and its calibration, the design, data processing and dissemination used in the COSMOS project, and give example time series of soil moisture obtained from COSMOS probes.
• Desilets, D., & Zreda, M. (1997). Spatial and temporal distribution of secondary cosmic-ray nucleon intensities and applications to in situ cosmogenic dating. EARTH AND PLANETARY SCIENCE LETTERS, 206(1-2), 21-42.
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  Cosmogenic nuclide production rates depend critically on the spatio-temporal distribution of cosmic-ray nucleon fluxes. Since the 1950s, measurements of the altitude, latitude and solar modulation dependencies of secondary cosmic-ray fluxes have been obtained by numerous investigators. However, until recently there has been no attempt to thoroughly evaluate the large body of modern cosmic-ray literature, to explain systematic discrepancies between measurements or to put these data into a rigorous theoretical framework appropriate for cosmogenic dating. The most important parameter to be constrained is the dependence of neutron intensity on atmospheric depth. Our analysis shows that effective nucleon attenuation lengths measured with neutron monitors over altitudes 0-5000 in range from 128 to 142 g cm(-2) at effective vertical cutoff rigidities of 0.5 and 14.9 GV, respectively. Effective attenuation lengths derived from thermal neutron data are somewhat higher, ranging from 134 to 155 g cm-2 at the same cutoff rigidities and over the same altitudes. We attribute the difference to a combination of two factors: the neutron monitor is more sensitive to the higher end of the nucleon energy spectrum, and the shape of the nucleon energy spectrum shifts towards lower energies with increasing atmospheric depth. We have derived separate scaling models for thermal neutron reactions and spallation reactions based on a comprehensive analysis of cosmic-ray survey data. By assuming that cosmic-ray intensity depends only on atmospheric depth and effective vertical cutoff rigidity, these models can be used to correct production rates for temporal changes in geomagnetic intensity using paleomagnetic records. (C) 2002 Elsevier Science B.V. All rights reserved.
• Phillips, F. M., Zreda, M. G., Gosse, J. C., Klein, J., Evenson, E. B., Hall, R. D., Chadwick, O. A., & Sharma, P. (1997). Cosmogenic 36Cl and 10Be ages of Quaternary glacial and fluvial deposits of the Wind River Range, Wyoming. Bulletin of the Geological Society of America, 109(11), 1453-1463.
• Phillips, F. M., Zreda, M. G., Gosse, J. C., Klein, J., Evenson, E. B., Hall, R. D., Chadwick, O. A., & Sharma, P. (1997). Cosmogenic ³⁶Cl and ¹⁰Be ages of Quaternary glacial and fluvial deposits of the Wind River Range, Wyoming. Bulletin of the Geological Society of America, 109(11), 1453-1463.
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  Abstract: We measured cosmogenic 36Cl in 56 samples from boulders on moraines and fluvial terraces in the vicinity of the Wind River Range, Wyoming. We also measured 10Be in 10 of the same samples. Most of the 10Be ages were in good agreement with the 36Cl ages, indicating that rock-surface erosion rates were very low. The oldest moraine investigated, the type Sacagewea Ridge site, yielded only a limiting minimum age of >232 ka. The oldest moraines in the type Bull Lake complex also could be constrained only to >130 ka. The main sequence of type Bull Lake moraines yielded age distributions indicating deposition within the intervals 130 to 100 ka and 120 to 100 ka; the best estimates are closer to the upper limits of these ranges, and associated uncertainties are in the range of 10% to 15%. These uncertainties could permit deposition in either marine isotope stage 6 or stage 5d. We found no evidence of glacial deposits dating to marine isotope stage 4. Both Bull Lake-age moraines from Fremont Lake, on the opposite side of the Wind River Range, and boulders on a fluvial terrace above the Wind River, gave age distributions very similar to that of the second oldest Bull Lake advance (ca. 130 to 100 ka). The distribution of boulder ages for Pinedale moraines at Bull Lake indicated deposition between 23 and 16 ka, nearly identical to the distribution of 10Be ages previously reported for the type Pinedale moraines at Fremont Lake.
• Yu, C., Warrick, A. W., Conklin, M. H., Young, M. H., & Zreda, M. (1997). Two- and three-parameter calibrations of time domain reflectometry for soil moisture measurement. WATER RESOURCES RESEARCH, 33(10), 2417-2421.
• Yu, C., Warrick, A. W., Conklin, M. H., Young, M. H., & Zreda, M. (1997). Two- and three-parameter calibrations of time domain reflectometry for soil moisture measurement. Water Resources Research, 33(10), 2417-2421.
• Bach, A., Dorn, R., Liu, T., Phillips, F. M., Zreda, M., Elmore, D., Elliott-Fisk, D. .., & Clark, J. (1996). Last 200,000 years of glacial history at Bishop Creek, Eastern Sierra Nevada, California. US Geological Survey Circular, 9-12.
• Bach, A., Dorn, R., Liu, T., Phillips, F. M., Zreda, M., Elmore, D., Elliott-Fisk, D., & Clark, J. (1996). Last 200,000 years of glacial history at Bishop Creek, Eastern Sierra Nevada, California. US Geological Survey Circular, 9-12.
• Desilets, D., Zreda, M., & Prabu, T. (1996). Extended scaling factors for in situ cosmogenic nuclides: New measurements at low latitude. EARTH AND PLANETARY SCIENCE LETTERS, 246(3-4), 265-276.
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  Production rates of cosmogenic nuclides at the earth's surface are controlled by the intensity of energetic cosmic-ray nucleons, which changes rapidly with elevation. An incomplete knowledge of how nucleon fluxes vary with elevation remains a major obstacle to utilizing cosmogenic nuclides as geochronometers in applications requiring highly accurate ages. One problem is that attenuation characteristics depend on nucleon energy. Measurements of high-energy (> 50 McV) nucleon fluxes tend to give shorter attenuation lengths than low-energy (< 1 MeV) fluxes, but these differences are not well characterized due to a lack of data at lower energies. Another problem is that the atmospheric attenuation length for nucleon fluxes varies with the geomagnetic cutoff rigidity (a parameter related to geomagnetic latitude), R-C, and that there has been an incomplete mapping of nucleon fluxes at high RC (low geomagnetic latitude). We report new measurements of nucleon fluxes from altitude transects in Hawaii (R-C = 12.8 GV) and Bangalore, India (R-C =17.3 GV). Our measurements in Hawaii of low-energy neutrons (median energy 1 eV) and energetic nucleons (median energy 140 MeV) confirm that nucleon scaling functions are energy-dependent in the range of energies at which cosmogenic nuclides are produced. Our measurements in southern India extend our previously reported scaling model for spallation reactions [D. Desilets, M. Zreda, Spatial and temporal distribution of secondary cosmic-ray nucleon intensity and applications to in situ cosmogenic dating. Earth Planet. Sci. Lett. 206 (2003) 21-42] from R-C = 13.3 GV to R-C = 17.3 GV, nearly the highest cutoff rigidity on earth. The anomalously high cutoff rigidity over India provides a geomagnetic shielding condition that is effectively the same as would be observed at the geomagnetic equator in a dipole field with an intensity 1.2 times the modern value. This makes it possible to scale low-latitude production rates to paleomagnetic fields that are stronger than the present dipole field. (c) 2006 Elsevier B.V All rights reserved.
• Dzierzek, J., Nitychoruk, J., Zreda, M. G., & Zreda-Gostyńska, G. (1996). Cosmogenic isotope 36CI - A new perspective for Quaternary chronostratigraphy of Poland. Kwartalnik Geologiczny, 40(3), 481-486.
• PHILLIPS, F., ZREDA, M., KU, T., LUO, S., HUANG, Q., ELMORE, D., KUBIK, P., & SHARMA, P. (1996). TH-230/U-234 AND CL-36 DATING OF EVAPORITE DEPOSITS FROM THE WESTERN QAIDAM BASIN, CHINA - IMPLICATIONS FOR GLACIAL-PERIOD DUST EXPORT FROM CENTRAL-ASIA. GEOLOGICAL SOCIETY OF AMERICA BULLETIN, 105(12), 1606-1616.
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  The western Qaidam Basin contains numerous hydrologically closed lakes and playas. We have measured uranium, thorium, and chlorine radioisotopes in sediments from drill cores at two of these, Gasikule Lake and Dalangtan dry plays, in order to date cycles of high and low lake level. The sediment chronologies from the two sub-basins are generally concordant, and the U/Th ages indicated transitions from high to low lake levels at 302 +/- 56 ka, at 138 +/-6 ka, and at 16.3 +/- 2.2 ka. These ages indicate that high lake stands in the Qaidam Basin were terminated at the end of continental glacial maxima. This result is unexpected because previously the large eolian dust fluxes out of Central Asia during glacial maxima have been considered to be associated with increased aridity in the region, not increased humidity. The lacustrine evidence, combined with previous data from ice cores, suggests instead that the persistence of strong winds may have played a more important role in enhanced dust fluxes than did variations in dust availability due to changes in aridity.
• Phillips, F. M., Zreda, M. G., Benson, L. V., Plummer, M. A., Elmore, D., & Sharma, P. (1996). Chronology for fluctuations in late Pleistocene Sierra Nevada glaciers and lakes. Science, 274(5288), 749-751.
• Phillips, F. M., Zreda, M. G., Flinsch, M. R., Elmore, D., & Sharma, P. (1996). A reevaluation of cosmogenic 36Cl production rates in terrestrial rocks. Geophysical Research Letters, 23(9), 949-952.
• Phillips, F. M., Zreda, M. G., Flinsch, M. R., Elmore, D., & Sharma, P. (1996). Reevaluation of cosmogenic ³⁶Cl production rates in terrestrial rocks. Geophysical Research Letters, 23(9), [d]949-952.
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  Abstract: We have measured 36Cl in a suite of 33 rock samples having well-constrained exposure histories and ages. The 36Cl production parameters were estimated by minimizing the squared deviations between the 36Cl and independent ages, yielding the following production parameters: spallation and muon production from Ca 2940±200 atoms 36Cl (mole Ca)-1 yr-1, spallation from K 6020±400 atoms 36Cl (mole K)-1 yr-1, and neutron production in air 586±40 fast neutrons (g air)-1 yr-1. The new production constants for spallation on Ca and thermal neutron activation are in good agreement with previous results, but that for spallation on K is about 50% larger.
• Phillips, F., Zreda, M., Evenson, E., Hall, R., Chadwick, O., & Sharma, P. (1995). Cosmogenic Cl-36 and Be-10 ages of Quaternary glacial and fluvial deposits of the Wind River Range, Wyoming. GEOLOGICAL SOCIETY OF AMERICA BULLETIN, 109(11), 1453-1463.
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  We measured cosmogenic Cl-36 in 56 samples from boulders on moraines and fluvial terraces in the vicinity of the Wind River Range, Wyoming. We also measured Be-10 in 10 of the same samples, Most of the Be-10 ages were in good agreement with the Cl-36 ages, indicating that rock-surface erosion rates were very low. The oldest moraine investigated, the type Sacagewea Ridge site, yielded only a limiting minimum age of >232 ka, The oldest moraines in the type Bull Lake complex also could be constrained only to >130 ka, The main sequence of type Bull Lake moraines yielded age distributions indicating deposition within the intervals 130 to 100 ka and 120 to 100 ka; the best estimates are closer to the upper limits of these ranges, and associated uncertainties are in the range of 10% to 15%, These uncertainties could permit deposition in either marine isotope stage 6 or stage 5d, We found no evidence of glacial deposits dating to marine isotope stage 4, Both Bull Lake-age moraines from Fremont Lake, on the opposite side of the Wind River Range, and boulders on a fluvial terrace above the Wind River, gave age distributions very similar to that of the second oldest Bull Lake advance (ca, 130 to 100 ka), The distribution of boulder ages for Pinedale moraines at Bull Lake indicated deposition between 23 and 16 ka, nearly identical to the distribution of Be-10 ages previously reported for the type Pinedale moraines at Fremont Lake.
• ZREDA, M., & ELMORE, D. (1995). DATING PALEOSEISMIC EVENTS AT CRATER FLAT, NEVADA BY COSMOGENIC CL-36 ACCUMULATION IN ASH DEPOSITED IN-GROUND FRACTURES. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 209, 24-NUCL.
• Zreda, M. G., & Phillips, F. M. (1995). Insights into alpine moraine development from cosmogenic 36Cl buildup dating. Geomorphology, 14(2), 149-156.
• Zreda, M. G., & Phillips, F. M. (1995). Insights into alpine moraine development from cosmogenic ³⁶Cl buildup dating. Geomorphology, 14(2), 149-156.
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  Abstract: We have used cosmogenic 36Cl surface exposure dating to determine apparent construction ages of late Pleistocene moraines in the Sierra Nevada, the White Mountains, and the Wind River Range, all in the western United States. The inferred glacial chronologies from the various localities all exhibit certain characteristics: (1) Local records are fragmentary and deposits of some glacial advances are always missing; no location has deposits of all glaciations and no glacial advance is recorded at all locations. This is due either to unfavorable conditions for glacier development at some times or to obliteration of earlier deposits by later, more extensive glaciers. (2) Most moraines have young apparent exposure ages, with only a few older than the last glacial cycle. This may be due to young true ages of these deposits, erosion of moraine surfaces, or obliterative overlap and covering of older deposits by younger ones. (3) Many deposits that were previously correlated (e.g., based on their stratigraphic positions) are not correlative; they may represent different stades and, sometimes, even different glaciations. Similarly, some previously uncorrelated deposits have the same exposure ages and may be correlative. (4) Clusters of several distinct moraines of nearly the same age are present at most locations. These clusters suggest that alpine moraines are formed during short deposition episodes that last between several hundred and several thousand years. © 1995.
• DEP, L., ELMORE, D., LIPSCHUTZ, M., VOGT, S., PHILLIPS, F. M., & ZREDA, M. (1994). DEPTH DEPENDENCE OF COSMOGENIC NEUTRON-CAPTURE-PRODUCED CL-36 IN A TERRESTRIAL ROCK. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS, 92(1-4), 301-307.
• Dep, L., Elmore, D., Lipschutz, M., Vogt, S., Phillips, F. M., & Zreda, M. (1994). Depth dependence of cosmogenic neutron-capture-produced 36C1 in a terrestrial rock. Nuclear Inst. and Methods in Physics Research, B, 92(1-4), 301-307.
• ZREDA, M., PHILLIPS, F., & ELMORE, D. (1994). COSMOGENIC CL-36 ACCUMULATION IN UNSTABLE LANDFORMS .2. SIMULATIONS AND MEASUREMENTS ON ERODING MORAINES. WATER RESOURCES RESEARCH, 30(11), 3127-3136.
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  Cosmogenic Cl-36 surface exposure ages obtained for multiple boulders from single landforms are usually characterized by a variance larger than that of the analytical methods employed. This excessive boulder-to-boulder variability, progressively more profound with increasing age of landforms, is due to removal of soil and gradual exposure of boulders at the surface. In our gradual exposure model, boulders are initially buried in moraine matrix. With time, erosion lowers the moraine surface and the boulders are gradually exposed to cosmic rays. Because the cosmic ray intensity changes with depth, the boulders are subjected to variable production rates of the cosmogenic Cl-36. Initial depth of boulders and their chemical composition are variable, which results in different amounts of the accumulated cosmogenic Cl-36 and thus different apparent ages of boulders. The shape of the resulting distribution of the apparent ages and the coefficient of variation depend on the erosion depth, while the first moment is a function of the true surface age and the erosion depth. These properties of the apparent age distributions permit calculation of the surface age, the erosion depth, and also the average erosion rate. We tested the model calculations using 26 boulders from a late Pleistocene moraine at Bishop Creek, Sierra Nevada, California. The set exhibited a bimodal distribution of the Cl-36 surface exposure ages. We interpreted the older mode as the result of gradual exposure and the younger one as the result of surficial processes other than soil removal. The 10 samples that constitute the older mode produced a distribution which closely matches the modeled distribution calculated using an age of 85 kyr and erosion depth of 570 g cm-2. This age is the same as an independent estimate obtained from cation ratio studies, and the calculated erosion depth is very close to the erosion depth of 600 g cm-2 based on a simple analytical model of soil erosion. These results indicate that our statistical model adequately describes effects of soil erosion on accumulation of cosmogenic Cl-36. The approach can be used to simultaneously obtain the true landform age and the erosion rate from apparent Cl-36 ages and therefore may help in evaluation of surface exposure ages of eroding landforms.
• Zreda, M. G., Phillips, F. M., & Elmore, D. (1994). Cosmogenic 36Cl accumulation in unstable landforms: 2. Simulations and measurements on eroding moraines. Water Resources Research, 30(11), 3127-3136.
• England, J., Atkinson, N., Dyke, A., Evans, D., & Zreda, M. (1993). Late wisconsinan buildup and wastage of the innuitian Ice Sheet across southern Ellesmere Island, Nunavut. CANADIAN JOURNAL OF EARTH SCIENCES, 41(1), 39-61.
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  During the Late Wisconsinan, a precursor of the Prince of Wales Icefield, southern Ellesmere Island, formed a prodigious ice divide of the Innuitian Ice Sheet. Initial buildup occurred after 19 ka BP, when the icefield advanced west (inland) across Makinson Inlet from margins similar to present. Subsequent reversal of flow to the east required ice divide migration to the west onto a plateau that is largely ice-free today. From this divide, a trunk glacier flowed eastward through Makinson Inlet to join the Smith Sound Ice Stream en route to nothern Baffin Bay. Westward flow from this divide filled Baumann Fiord, depositing a granite dispersal train that extends a further 600 km across the archipelago to the polar continental shelf. Deglaciation of most of Makinson Inlet occurred catastrophically at similar to9.3 ka BP, forming a calving bay that thinned the Innuitian divide, thereby triggering deglaciation of most of Baumann Fiord by 8.5 ka BP. Ninety C-14 dates on Holocene shells and driftwood constrain deglacial isochrones and postglacial emergence curves on opposite sides of the former Innuitian divide. Isobases drawn on the 8 ka BP shoreline rise northwest towards Eureka Sound, the axis of maximum former ice thickness. Ice margins on Ellesmere Island were similar to present from similar to50-19 ka BP (spanning marine isotope stages 3 and 2). However, significant regional variation in ice extent during this interval is recorded by ice rafting from the Laurentide Ice Sheet into Baffin Bay. Later buildup of the Innuitian Ice Sheet occurred during the low global sea level that defines the last glacial maximum (18 ka BP). We also suggest that the Innuitian Ice Sheet was influenced by the buttressing and subsequent removal of the Greenland Ice Sheet along eastern Ellesmere Island.
• Phillips, F. M., Zreda, M. G., Ku, T., Luo, S., Huang, Q., Elmore, D., Kubik, P. W., & Sharma, P. (1993).

  230Th/234U and 36Cl dating of evaporite deposits from the western Qaidam Basin, China: Implications for glacial-period dust export from Central Asia

  . Geological Society of America Bulletin, 105(12), 1606-1616. doi:10.1130/0016-7606(1993)105<1606:tuacdo>2.3.co;2
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  The western Qaidam Basin contains numerous hydrologically closed lakes and playas. We have measured uranium, thorium, and chlorine radioisotopes in sediments from drill cores at two of these, Gasikule Lake and Dalangtan dry playa, in order to date cycles of high and low lake level. The sediment chronologies from the two sub-basins are generally concordant, and the U/Th ages indicate transitions from high to low lake levels at 302 ± 56 ka, at 138 ± 6 ka, and at 16.3 ± 2.2 ka. These ages indicate that high lake stands in the Qaidam Basin were terminated at the end of continental glacial maxima. This result is unexpected because previously the large eolian dust fluxes out of Central Asia during glacial maxima have been considered to be associated with increased aridity in the region, not increased humidity. The lacustrine evidence, combined with previous data from ice cores, suggests instead that the persistence of strong winds may have played a more important role in enhanced dust fluxes than did variations in dust availability due to changes in aridity.
• Zreda, M. G., Phillips, F. M., Kubik, P. W., Sharma, P., & Elmore, D. (1993). Cosmogenic 36 Cl dating of a young basaltic eruption complex, Lathrop Wells, Nevada. Geology, 21(1), 57-60.
• Zreda, M. G., Phillips, F. M., Kubik, P. W., Sharma, P., & Elmore, D. (1993). Cosmogenic ³⁶Cl dating of a young basaltic eruption complex, Lathrop Wells, Nevada. Geology, 21(1), 57-60.
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  Abstract: It has been proposed that the Lathrop Wells volcanic center, a late Quaternary basaltic complex in southern Nevada, has erupted more than once. In common with most Quaternary basalts, this volcanic center has proved difficult to date by K/Ar and other commonly employed methods. The accumulation of 36Cl in 11 samples from lava flows and volcanic bombs was measured, producing a combined average age of 81 ± 7.9 ka, with no systematic differences between sample subsets collected from different volcanic features. The 36Cl dates do not supprt a history of multiple eruptions, but neither do they completely preclude the possibility. -Authors
• Zreda, M., Desilets, D., Ferre, T. P., & Scott, R. L. (1993). Measuring soil moisture content non-invasively at intermediate spatial scale using cosmic-ray neutrons. GEOPHYSICAL RESEARCH LETTERS, 35(21).
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  Soil moisture content on a horizontal scale of hectometers and at depths of decimeters can be inferred from measurements of low-energy cosmic-ray neutrons that are generated within soil, moderated mainly by hydrogen atoms, and diffused back to the atmosphere. These neutrons are sensitive to water content changes, but largely insensitive to variations in soil chemistry, and their intensity above the surface is inversely correlated with hydrogen content of the soil. The management with a portable neutron detector placed a few meters above the ground takes minutes to hours, permitting high-resolution, long-term monitoring of undistributed soil moisture conditions. The large footprint makes the method suitable for weather and short-term climate forecast intialization and for calibration of satellite sensors, and the measurement a-depth makes the probe ideal for studies of plant/soil interaction and atmosphere/soil exchange. Citation: Zreda, M., D. Desilets, T. P. A. Ferre, and R. L. Scott (2008), Measuring soil moisture content non-invasively at intermediate spatial scale using cosmic-ray neutrons, Geophys. Res. Lett., 35, L21402, doi: 10.1029/2008GL035655.
• ELMORE, D., DEP, L., LIPSCHUTZ, M., VOGT, S., PHILLIPS, F. N., & ZREDA, M. (1992). FUNDAMENTALS OF SURFACE EXPOSURE DATING. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 203, 14-NUCL.
• DORN, R. I., PHILLIPS, F. M., ZREDA, M. G., WOLFE, E. W., JULL, A., DONAHUE, D. J., KUBIK, P. W., & SHARMA, P. (1991). GLACIAL CHRONOLOGY. RESEARCH & EXPLORATION, 7(4), 456-471.
• Desilets, D., & Zreda, M. (1991). On scaling cosmogenic nuclide production rates for altitude and latitude using cosmic-ray measurements. EARTH AND PLANETARY SCIENCE LETTERS, 193(1-2), 213-225.
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  The wide use of cosmogenic nuclides for dating terrestrial landforms has prompted a renewed interest in characterizing the spatial distribution of terrestrial cosmic rays. Cosmic-ray measurements from neutron monitors, nuclear emulsions and cloud chambers have played an important role in developing new models for scaling cosmic-ray neutron intensities and, indirectly, cosmogenic production rates. Unfortunately, current scaling models overlook or misinterpret many of these data. In this paper, we describe factors that must be considered when using neutron measurements to determine scaling formulations for production rates of cosmogenic nuclides. Over the past 50 years, the overwhelming majority of nucleon flux measurements have been taken with neutron monitors. However. in order to use these data for scaling spallation reactions, the following factors must be considered: (1) sensitivity of instruments to muons and to background, (2) instrumental biases in energy sensitivity, (3) solar activity, and (4) the way of ordering cosmic-ray data in the geomagnetic field. Failure to account for these factors can result in discrepancies of as much as 7% in neutron attenuation lengths measured at the same location. This magnitude of deviation can result in an error on the order of 20% in cosmogenic production rates scaled from 4300 in to sea level. The shapes of latitude curves of nucleon flux also depend on these factors to a measurable extent. thereby causing additional uncertainties in cosmogenic production rates, The corrections proposed herein significantly improve our ability to transfer scaling formulations based on neutron measurements to scaling formulations applicable to spallation reactions, and. therefore. constitute an important advance in cosmogenic dating methodology. (C) 2001 Elsevier Science BN. All rights reserved.
• Phillips, F. M., Zreda, M. G., Smith, S. S., Elmore, D., Kubik, P. W., Dorn, R. I., & Roddy, D. J. (1991). Age and geomorphic history of Meteor Crater, Arizona, from cosmogenic 36Cl and 14C in rock varnish. Geochimica et Cosmochimica Acta, 55(9), 2695-2698.
• Zreda, M. G., Phillips, F. M., Elmore, D., Kubik, P. W., Sharma, P., & Dorn, R. I. (1991). Cosmogenic chlorine-36 production rates in terrestrial rocks. Earth and Planetary Science Letters, 105(1-3), 94-109.
• Zreda, M., & Phillips, F. (1991). Insights into alpine moraine development from cosmogenic Cl-36 buildup dating. GEOMORPHOLOGY, 14(2), 149-156.
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  We have used cosmogenic Cl-36 surface exposure dating to determine apparent construction ages of late Pleistocene moraines in the Sierra Nevada, the White Mountains, and the Wind River Range, all in the western United States. The inferred glacial chronologies from the various localities all exhibit certain characteristics: (1) Local records are fragmentary and deposits of some glacial advances are always missing; no location has deposits of all glaciations and no glacial advance is recorded at all locations. This is due either to unfavorable conditions for glacier development at some times or to obliteration of earlier deposits by later, more extensive glaciers. (2) Most moraines have young apparent exposure ages, with only a few older than the last glacial cycle. This may be due to young true ages of these deposits, erosion of moraine surfaces, or obliterative overlap and covering of older deposits by younger ones. (3) Many deposits that were previously correlated (e.g., based on their stratigraphic positions) are not correlative; they may represent different stades and, sometimes, even different glaciations. Similarly, some previously uncorrelated deposits have the same exposure ages and may be correlative. (4) Clusters of several distinct moraines of nearly the same age are present at most locations. These clusters suggest that alpine moraines are formed during short deposition episodes that last between several hundred and several thousand years.
• Bell, J., Brune, J., Liu, T., Zreda, M., & Yount, J. (1990). Dating precariously balanced rocks in seismically active parts of California and Nevada. GEOLOGY, 26(6), 495-498.
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  Precariously balanced boulders that could be knocked down by strong earthquake ground motion are found in some seismically active areas of southern California and Nevada In this study we used two independent surface-exposure dating techniques-rock-varnish microlamination and cosmogenic (CI)-C-36 dating methodologies-to estimate minimum-and maximum-limiting ages, respectively, of the precarious boulders and by inference the elapsed time since the sites were shaken down. The results of the exposure dating indicate that all of the precarious rocks are >10.5 ka and that some may be significantly older At Victorville and Jacumba, California, these results show that the precarious rocks have not been knocked do,vn for at least 10.5 ky., a conclusion in apparent conflict with some commonly used probabilistic seismic hazard maps. At Yucca Mountain, Nevada, the ages of the precarious rocks are >10.5 to >27.0 ka, providing an independent measure of the minimum time elapsed since faulting occurred on the Solitario Canyon fault.
• Phillips, F. M., Zreda, M. G., Smith, S. S., Elmore, D., Kubik, P. W., & Sharma, P. (1990). Cosmogenic chlorine-36 chronology for glacial deposits at Bloody Canyon, Eastern Sierra Nevada. Science, 248(4962), 1529-1532.
• Phillips, F. M., Zreda, M. G., Smith, S. S., Elmore, D., Kubik, P. W., & Sharma, P. (1990). Cosmogenic chlorine-36 chronology for glacial deposits at bloody canyon, Eastern Sierra Nevada. Science, 248(4962), 1529-1532.
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  PMID: 17818313;Abstract: Deposits from mountain glaciers provide an important record of Quaternary climatic fluctuations but have proved difficult to date directly. A chronology has been obtained for glacial deposits at Bloody Canyon, California, by measurement of the accumulation of chlorine-36 produced by cosmic rays in boulders exposed on moraine crests. The accumulation of chlorine-36 indicates that episodes of glaciation occurred at about 21, 24, 65, 115, 145, and 200 ka (thousand years ago). Although the timing of the glaciations correlates well with peaks of global ice volume inferred from the marine oxygen isotope record, the relative magnitudes differ markedly. The lengths of the moraines dating from 115 ka and 65 ka show that the early glacial episodes were more extensive than those during the later Wisconsin and indicate that the transition from interglacial to full glacial conditions was rapid.

Proceedings Publications

• Bieszczad, J., Gilmore, R., Ueckermann, M., & Zreda, M. (2019).

  SoilMAP: An Open Source Python Library for Developing Algorithms and Specialized User Interfaces that Integrate Multiple Disparate Data Sources Including Near-Real-Time Sensor Data for Streamlined Monitoring of Experiments and Analysis.

  . In AGU Meeting.
• Zreda, M. G. (2018, October). Cosmic-ray hydrology: principles and detectors. In TERENO International Conference 2018.
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  I was invited to give a keynote address on the subject of cosmic-ray hydrology.
• Chan, S., Bindlish, R., O'Neill, P., Jackson, T., Chaubell, J., Piepmeier, J., Dunbar, S., Colliander, A., Chen, F., Entekhabi, D., Yueh, S., Cosh, M., Caldwell, T., Walker, J., Wu, X., Berg, A., Rowlandson, T., Pacheco, A., McNairn, H., , Thibeault, M., et al. (2017). Development and validation of the SMAP enhanced passive soil moisture product.
• Montzka, C., Bogena, H. R., Zreda, M., Monerris, A., Morrison, R., Muddu, S., & Vereecken, H. (2017). Cosmic-ray neutron probes for satellite soil moisture validation.
• O'neill, P. E., Chan, S., Bindlish, R., Jackson, T. J., Colliander, A., Dunbar, S., Chen, F., Piepmeier, J. R., Yueh, S., Entekhabi, D., Cosh, M. H., Caldwell, T. G., Walker, J. P., Wu, X., Berg, A. A., Rowlandson, T., Pacheco, A., Mcnairn, H., Thibeault, M., , Martinez-fernandez, J., et al. (2017).

  Assessment of version 4 of the SMAP passive soil moisture standard product

  . In 2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 3941-3944.
• O'Neill, P., Chan, S., Colliander, A., Dunbar, S., Njoku, E., Bindlish, R., Chen, F., Jackson, T., Burgin, M., Piepmeier, J., Yueh, S., Entekhabi, D., Cosh, M., Caldwell, T., Walker, J., Wu, X., Berg, A., Rowlandson, T., Pacheco, A., , McNairn, H., et al. (2016). Evaluation of the validated Soil Moisture product from the SMAP radiometer.
• O'Neill, P., Chan, S., others, 2., Zreda, M., & others, t. (2016, April). Evaluation of the validated soil moisture product from the SMAP radiometer. In 2016 IEEE International Geoscience & Remote Sensing Symposium.
• Andreasen, M., Bogena, H., Desilets, D., Jensen, K. H., Looms*, M. C., Sonnenborg, T. O., & Zreda, M. (2014).

  Cosmic-ray neutron intensity measurements of soil moisture – A case study in the Skjern catchment, Denmark

  . In 2014 SEG Annual Meeting, Denver, Colorado, USA, October 2014.
• Andreasen, M., Looms, M. C., Bogena, H., Desilets, D., Zreda, M. G., Sonnenborg, T. O., & Jensen, K. H. (2014).

  The potential of detecting intermediate-scale biomass and canopy interception in a coniferous forest using cosmic-ray neutron intensity measurements and neutron transport modeling

  . In AGU Meeting.
• Andreasen, M., Looms, M. C., Jensen, K. H., Sonnenborg, T. O., Bogena, H., Desilets, D., & Zreda, M. (2014). Cosmic-ray neutron intensity measurements of soil moisture - A case study in the Skjern catchment, Denmark.
• De, V. L., Anderson, K., Zreda, M., Zweck, C., & Bradley, L. (2013). Forensic reasoning about paleoclimatology.
• Walker, J. P., Dumedah, G., Monerris, A., Gao, Y., Rüdiger, C., Wu, X., Panciera, R., Merlin, O., Pipunic, R., Ryu, D., & Zreda, M. (2012). High resolution soil moisture mapping.
• Zreda, M., Ferre, T. P., & Franz, T. E. (2012).

  Understanding the Spatiotemporal Distribution of Soil Moisture at Intermediate Spatial Scales Using Geophysical Methods

  . In Symposium on the Application of Geophysics to Engineering and Environmental Problems 2012, 256-256.
• Zreda, M., Ferre, T. P., Shuttleworth, W. J., Zeng, X., & Zweck, C. (2010).

  The COsmic-ray Soil Moisture Observing System (COSMOS): a non-invasive, intermediate scale soil moisture measurement network

  . In Role of hydrology in managing consequences of a changing global environment.
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  Soil moisture at a horizontal scale of around 700 m and depths of 15 to 70 cm can be inferred from measurements of cosmic-ray neutrons that are generated within soil, moderated mainly by the hydrogen atoms in water, and emitted back to the atmosphere. The intensity of the resulting field of neutrons above the ground is sensitive to water content changes, largely insensitive to soil chemistry and inversely correlated with hydrogen content of the soil. Measurement of this intensity with a portable neutron detector placed above the ground takes minutes to hours, permitting highresolution, long-term monitoring of undisturbed soil moisture. The large footprint makes the method suitable for weather and short-term climate forecast initialization and satellite validation, while the measurement depth makes the probe ideal for studying plant/soil/atmosphere interactions. The intensity of cosmic-ray neutrons is also sensitive to water above the ground in snow, vegetation, or intercepted water, this water being in principle distinguishable from soil moisture. Instruments using this method are being deployed in the COsmic-ray Soil Moisture Observing System (COSMOS), which comprises initially a network of 50 probes (to provide a proof of concept) and subsequently 500 probes distributed across the contiguous USA. Additional COSMOS probes are also now being deployed on an experimental basis in the UK, Australia, and China.
• Anderson, K., Bradley, E., Zreda, M., Rassbach, L., Zweck, C., & Sheehan, E. (2007). ACE: Age Calculation Engine - A design environment for cosmogenic dating techniques.
• Sarikaya, M. A., Ciner, A., & Zreda, M. G. (2003).

  Erciyes volkanı Geç Kuvaterner buzul çökelleri

  . In gdsgd.
• Phillips, F. M., Gosse, J. C., Liu, B., Fabryka-martin, J., Zreda, M. G., Klein, J., Evenson, E. B., & Sharma, P. (1995).

  High-resolution estimation of surface exposure histories using (super 36) Cl together with a spallogenic nuclide

  . In AGU Meeting, EOS, Transactions, American Geophysical Union.

Presentations

• Zreda, M. G. (2018, April). Cosmic-ray hydrology: principles and detectors. Invited lecture at CEH, Wallingford, UK. Centre for Ecology and Hydrology, Wallingford, UK: Centre for Ecology and Hydrology, Wallingford, UK.
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  Invited lecture of the state of the art in cosmic-ray detectors for hydrological application. This was part of my consulting for CEH.
• Zreda, M. G. (2018, April). Geologia i hydrologia z użyciem promieni kosmicznych (Geology and hydrology using cosmic rays). Invited lecture at University of Warsaw, Poland. Department of Geology, University of Warsaw, Warsaw, Poland.
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  I was invited to present the current research on cosmic-ray geology and hydrology. The attendees came from the University of Warsaw, the Geological Institute and the Polish Academy of Sciences.
• Zreda, M. G. (2018, May). Cosmic-ray hydrology: principles and detectors. Invited lecture at NVE, Oslo, Norway. Norges vassdrags- og energidirektorat (NVE), Oslo, Norway: Norges vassdrags- og energidirektorat (NVE), Oslo, Norway.
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  Presentation on cosmic-ray hydrology and instrumentation used to measure water at the land surface.Invited by:Norges vassdrags- og energidirektorat(The Norwegian Water Resources and Energy Directorate)
• Cosh, M., Ochsner, T., McKee, L., Coopersmith, E., Dong, J., Small, E., Zreda, M. G., & Qu, J. (2017, 12). Soil moisture monitoring with long term in situ sensors: Lessons from MOISST. 2017 Fall Meeting, AGU, New Orleans, LA, 11-15 Dec. New Orleans, LA: American Geophysical Union (AGU).
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  Paper 239092.
• Schroen, M., Bannehr, L., Koehli, M., Zreda, M. G., & others, 8. (2017, 12). Airborne Detection of Cosmic-Ray Albedo Neutrons for Regional-Scale Surveys of Root-Zone Soil Water on Earth. 2017 Fall Meeting, AGU, New Orleans, LA, 11-15 Dec. New Orleans, LA: American Geophysical Union (AGU).
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  Paper number 226068.
• Zreda, M. G., Schroen, M., & Koehli, M. (2017, 12). Technological advances in cosmogenic neutron detectors for measuring soil water content (Invited). 2017 Fall Meeting, AGU, New Orleans, LA, 11-15 Dec. New Orleans: American Geophysical Union (AGU).
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  Paper number 258128.

Others

• Jackson, T., others, 3., Zreda, M., & others, f. (2016, 12). Soil Moisture Active Passive (SMAP) Project: Calibration and Validation for the L2/3_SM_P Version 4 and L2/3_SM_P_E Version 1 Data Products. NASA-JPL.
• Walker, J. P., others, n., & Zreda, M. G. (2016, July). High resolution soil moisture mapping. Computing Ethics: A Multicultural Approach.
• Zreda, M. G., others, 2., O'Neill, P., & others, t. (2016, July). Evaluation of the validated soil moisture product from the SMAP radiometer. NASA Goddard Space Flight Center.
• PHILLIPS, F., ZREDA, M., SMITH, S., ELMORE, D., KUBIK, P., DORN, R., & RODDY, D. (2006, SEP). AGE AND GEOMORPHIC HISTORY OF METEOR CRATER, ARIZONA, FROM COSMOGENIC CL-36 AND C-14 IN ROCK VARNISH. GEOCHIMICA ET COSMOCHIMICA ACTA.
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  Using cosmogenic Cl-36 buildup and rock varnish radiocarbon, we have measured the exposure age of rock surfaces at Meteor Crater, Arizona. Our Cl-36 measurements on four dolomite boulders ejected from the crater by the impact yield a mean age of 49.7 +/- 0.85 ka, which is in excellent agreement with an average age of 49 +/- 3 ka obtained from thermoluminescence studies on shock-metamorphosed dolomite and quartz. These ages are supported by undetectably low C-14 in the oldest rock varnish sample.