Amanda Nicole Hughes

Interests

Teaching

Cross-disciplinary course offerings in geology/geophysics/rock mechanics, integrating pure and applied concepts in course content, integrating computer-based skills and real-world geoscience data with fundamental concepts in lab exercises, training students to understand the subsurface for careers in energy and mineral exploration, developing new resources for improving spatial reasoning and visualization of large earth science datasets, and improving accessibility of field activities in the geosciences.

Research

1) Characterizing the mechanics that control of the growth of geologic structures at a range of spatial and temporal scales,2) Developing and testing quantitative methods for predicting the geometry and distribution of faults, folds, fractures, and stress in the Earth's crust,3)Integrated analysis of detailed field observations, geophysical observations, and model-based insights for understanding and characterizing the geometry geologic structures, 4) Detailed tectonic and geologic characterization of geologic structures in fold and thrust belts, salt basins, rift margins, and diffuse transform margins,5) Characterizing the role of faults and fractures in providing pathways and mechanisms for fluid migration through the brittle crust in hydrologic, energy and mineral resource formation, and seismological applications.6) Reconciling understanding of stress and strain in the crust across earthquake-cycle to tectonic timescales7) Mechanical modeling methods (DEM, FEM, BEM), algorithm development for structural geology applications, applications of computer vision, AI, and fitness optimization methods to addressing issues in subsurface structural geometry characterization and prediction.

Courses

Scholarly Contributions

Books

• Davis, G. H., Bos Orent, E., Clinkskales, C., Ferroni, F., Gehrels, G. E., George, S. W., Hanagan, C. E., Hughes, A. N., Iriondo, A., Jepson, G., Kelty, C., Krantz, R. W., Levenstein, B. M., Lingrey, S. H., Miggins, D. P., Moore, T., Portnoy, S. E., Reeher, L. J., & Wang, J. W. (2023). Structural Analysis and Chronologic Constraints on Progressive Deformation within the Rincon Mountains, Arizona: Implications for Development of Metamorphic Core Complexes. Geological Society of America Memoir 222. doi:10.1130/2023.1222(01)

Chapters

• Davis, G. H., Orent, E. B., Clinkscales, C., Ferroni, F. R., Gehrels, G. E., George, S. W., Guns, K. A., Hanagan, C. E., Hughes, A., Iriondo, A., Jepson, G., Kelty, C., Krantz, R. W., Levenstein, B. M., Lingrey, S. H., Miggins, D. P., Moore, T., Portnoy, S. E., Reeher, L. J., & Wang, J. W. (2023). Structural Analysis and Chronologic Constraints on Progressive Deformation within the Rincon Mountains, Arizona: Implications for Development of Metamorphic Core Complexes. In Structural Analysis and Chronologic Constraints on Progressive Deformation within the Rincon Mountains, Arizona: Implications for Development of Metamorphic Core Complexes(pp 1-125). Geological Society of America. doi:10.1130/2023.1222(01)

Journals/Publications

• Henriquez, S., Decelles, P. G., Carrapa, B., & Hughes, A. N. (2023). Kinematic evolution of th central Andean retroarc thrust belt in northwestern Argentina and implications for coupling between shortening and crustal thickening. Geological Society of America Bulletin, 135(1-2), 81-103.
• Reeher, L. J., Hughes, A. N., Davis, G. H., Kemeny, J. M., & Ferrill, D. A. (2023). Finding the right place in Mohr circle space: Geologic evidence and implications for applying a non-linear failure criterion to fractured rock. Journal of Structural Geology, 166, 104773.
• Dunham, A. M., Kiser, E., Kargel, J. S., Haritashya, U. K., Watson, C. S., Shugar, D. H., Hughes, A., & DeCelles, P. G. (2022). Topographic Control on Ground Motions and Landslides From the 2015 Gorkha Earthquake. Geophysical Research Letters, 49(10). doi:10.1029/2022gl098582
• Hanagan, C., Bennett, R. A., Chiaraluce, L., Hughes, A., & Cocco, M. (2022). Implications of Receiver Plane Uncertainty for the Static Stress Triggering Hypothesis. Journal of Geophysical Research: Solid Earth, 127(5). doi:10.1029/2021jb023589
• Connors, C. D., Hughes, A. N., & Ball, S. M. (2021). Forward kinematic modeling of fault-bend folding. Journal of Structural Geology, 143. doi:10.1016/j.jsg.2020.104252
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  Abstract We present a forward numerical modeling approach for fault-bend folding based on a velocity description of deformation. The approach incorporates algorithms capable of modeling multiple fault bends of different geometries (e. g. fault bends not stepping up from a detachment), imbricates, and variable velocity-boundary orientations, with corresponding varying slip ratios. When modeling contraction, the approach is capable of reproducing rounded-hinges and parallel folds with localized bed thinning or thickening commonly observed in natural structures. Extensional fault-bend folds can be modeled using the same set of equations, with the minor modification that velocity boundary orientations are defined independently of the fault shape. The modeled structures conserve area, and commonly observed features of extensional fault-bend folds, such as rollover structures with growth, are produced. Thus, we present a unified inclined-shear and flexural-slip general transformation associated with displacement over bends in faults, describing the theoretical framework which we have implemented in the associated program, fbfFor. We show the utility of this kinematic approach by matching seismic reflection examples, analog models, and mechanical models of fault-bend folds to create progressive, balanced kinematic interpretations and gain further insight into the formation of these structures.
• Henriquez, S., Decelles, P. G., Carrapa, B., Hughes, A. N., Davis, G. H., & Alvarado, P. (2021). Corrigendum to “Deformation history of the Puna plateau, Central Andes of northwestern Argentina” [J. Struct. Geol. 140 (2020) 104133]. Journal of Structural Geology, 146. doi:10.1016/j.jsg.2020.104245
• Kiser, E., Kehoe, H., Chen, M., & Hughes, A. (2021). Lower Mantle Seismicity Following the 2015 Mw 7.9 Bonin Islands Deep‐Focus Earthquake. Geophysical Research Letters, 48(13). doi:10.1029/2021gl093111
• Henriquez, S., Decelles, P. G., Carrapa, B., Hughes, A. N., Davis, G. H., & Alvarado, P. (2020). Deformation history of the Puna plateau, Central Andes of northwestern Argentina. Journal of Structural Geology, 140. doi:10.1016/j.jsg.2020.104133
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  Abstract Two tectonic shortening events created the first-order structural characteristics of the Puna plateau: one in the Paleozoic and a second during the Andean Orogeny in the Cenozoic. To constrain the structural characteristics and timing of Andean deformation in the Puna plateau, we focus on differentiating these two shortening events and provide cooling ages (apatite fission track and apatite (U–Th)/He) to determine the amount of Andean exhumation on the hanging-wall of major Cenozoic faults. Two contrasting expressions of shortening are documented. In Ordovician strata, strain requires four stages: folding, flattening through cleavage formation, low-angle faulting and local distributed shear. In the Mesozoic and Cenozoic strata, shortening is expressed as reverse faults, fault-propagation folds and dipping panels. Dissimilarities reflect different P-T conditions and amount of strain, as structures in the Ordovician rocks require higher temperatures and strain than Andean structures in the Mesozoic and Cenozoic strata. Furthermore, local Cretaceous AFT cooling ages in pervasively cleaved Ordovician rocks reveal these rocks did not reach temperatures compatible with cleavage formation during the Andean event. Lastly, our data show a middle Eocene to Oligocene exhumation history that supports an overall continuous development of the Andean thrust belt in the Puna plateau since the early Cenozoic.
• Hughes, A. N. (2020). Mechanical Controls on Structural Styles in Shortening Environments: A Discrete-element Modelling Approach. Geological Society, London, Special Publications, 490, 33-55. doi:10.1144/SP490-2019-114
• Eichelberger, N. W., Nunns, A. G., Groshong Jr., R. H., & Hughes, A. N. (2017). Direct estimation of fault trajectory from structural relief. AAPG Bulletin, 101(5), 635-653. doi:10.1306/08231616065
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  ABSTRACT Confidently defining the trajectory of faults that control structural traps is a recurring challenge for seismic interpreters. In regions with fault-related folds, seismic and well data often constrain the upper fold geometry, but the location and displacement of the controlling fault are unknown. We present a generalized area–depth strain (ADS) analysis method that uses the observed depth variation in deformed horizon areas to directly estimate underlying fault depth, dip, displacement, and layer-parallel strain from a structural interpretation. Previously established ADS methods are only applicable to structures controlled by faults that sole into layer-parallel detachments. The new technique, referred to as the fault-trajectory method, generalizes ADS analysis to contractional and extensional structures controlled by fault ramps that cut across layers and displace the regional. For structures where area is conserved during deformation and shear is minimal, laterally shifting the analysis limits across the structure defines changes in fault orientation. We validate the method by applying it to numerical forward models, analog clay models, and seismically imaged structures from the San Joaquin basin in California, the Sierras Pampeanas in Argentina, and the North Sea. The fault-trajectory method is shown to be robust, because it exactly reproduces the prescribed fault trajectories and displacements used to construct the numerical and analog models. In the natural examples, the ADS-estimated fault trajectories are consistent with independent fault-location constraints such as earthquake focal mechanisms, seismic imaging, and forward modeling.
• Olyphant, J. R., Johnson, R. A., & Hughes, A. N. (2017). Evolution of the Southern Guinea Plateau: Implications on Guinea-Demerara Plateau formation using insights from seismic, subsidence, and gravity data. Tectonophysics, 717, 358-371. doi:10.1016/j.tecto.2017.08.036
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  Abstract The Guinea Plateau (offshore Guinea) and its conjugate, the Demerara Plateau (offshore French Guiana), comprise two of the most prominent passive continental margins in the Atlantic Ocean. The conjugate plateaus formed as a result of two periods of rifting, the Jurassic opening of the Central Atlantic Ocean and the northward-propagating Cretaceous opening of the Southern Atlantic Ocean. Although several studies are published on the Demerara Plateau that explain the evolution of its multi-rift history and the effect of rifting on its distinct geometry, the Guinea Plateau, and in particular its south-eastern margin, remain relatively unexplored in the literature. Here we present interpretations of the structure and evolution of the Guinea Plateau using recent 2-D and 3-D seismic-reflection data collected at the intersection of the southern and eastern margins. We substantiate our study with calculated subsidence curves at four locations along the southern margin, as well as two 2-D gravity forward models along regional seismic-reflection profiles to estimate stretching factors (β) and crustal thicknesses. We combine our results with previous studies concerning the south-western Guinea margin, and compare them to published interpretations regarding the conjugate margins of the Demerara Plateau. The resolved amounts of rift-related volcanism, listric-style normal faults, and moderate stretching factors suggest that a component of upper-crustal asymmetry (simple shear) and depth-dependent stretching may have persisted at the Demerara-Guinea conjugate margins during Cretaceous rifting of the equatorial segment of the Southern Atlantic Ocean.
• Carrapa, B., Giulio, A. D., Mancin, N., Stockli, D. F., Fantoni, R., Hughes, A. N., & Gupta, S. (2016). Tectonic significance of Cenozoic exhumation and foreland basin evolution in the Western Alps. Tectonics, 35(8), 1892-1912. doi:10.1002/2016tc004132
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  The Alps are the archetypical collisional orogenic system on Earth and yet our understanding of processes controlling topographic growth in the Cenozoic remains incomplete. Whereas ideas and models on the Alps are abundant, data from the foreland basin record able to constrain the timing of erosion and sedimentation, mechanisms of basin accommodation and basin deformation are sparse. We combine seismic stratigraphy, micropaleontology, white mica 40Ar/39Ar, detrital zircon (U-Th)/He and apatite fission track thermochronology to Miocene-Pliocene samples from the retro-wedge foreland basin (Saluzzo Basin in Italy) and to Oligocene-Miocene sedimentary rocks from the pro-wedge foreland basin (Bârreme Basin in France) of the Western Alps. Our new data show that exhumation in the Oligocene-Miocene was non uniform across the Western Alps. Topographic growth was underway since the Oligocene and exhumation was concentrated on the pro-side of the orogenic system. Rapid and episodic early Miocene exhumation of the Western Alps was concentrated instead on the retro-side of the orogen and correlates with a major unconformity in the proximal retro-foreland basin. A phase of orogenic construction is recorded by exhumation of the proximal pro-foreland in both the Central and Western Alps at ca. 16 Ma. This is associated with high sedimentation rates, and by inference erosion rates, and suggests that an increase in accretionary flux associated with the dynamics of subduction of Europe under Adria controlled orogenic expansion in the Miocene.
• Eichelberger, N. W., Hughes, A. N., & Nunns, A. G. (2015). Combining multiple quantitative structural analysis techniques to create robust structural interpretations. Interpretation, 3(4), SAA89-SAA104. doi:10.1190/int-2015-0016.1
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  AbstractCarefully selected 2D transects contain an abundance of structural information that can constrain 3D analyses of petroleum systems. Realizing the full value of the information in a 2D transect requires combining multiple, independent structural analysis techniques using fully interactive tools. Our approach uses quantitative structural geologic software that instantaneously displays structural computations and analyses, eliminating time-intensive manual measurements and calculations. By quickly testing multiple hypotheses, we converged on an optimal solution that is consistent with available data. We have combined area-depth-strain (ADS) analysis, structural restoration, and forward modeling of a structural interpretation of a fault-propagation fold in the Niger Delta. These methods confirmed the original interpretation and furthermore quantified displacement, strain, detachment depth, and kinematic history. ADS analysis validated the interpreted detachment depth and revealed significant layer-par...
• Hughes, A. N., & Shaw, J. H. (2015). Insights into the mechanics of fault-propagation folding styles. Geological Society of America Bulletin, 127(11-12), 1752-1765. doi:10.1130/b31215.1
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  Fault-propagation folds are common structures that accommodate crustal shortening in various compressional settings worldwide. Motivated by the wide range of geometries observed for fault-propagation folds, we investigated the role played by mechanics in the variations observed for this structural class. Detailed structural measurements of a series of 15 fault-propagation folds from the Niger Delta, Argentina, and southeastern Asia reveal several relationships between aspects of the structural geometries. We found that the decrease in displacement updip along the fault is well approximated by a linear trend that has a relatively consistent slope, and that this gradient remains constant for increasing total displacement. This suggests that the faults propagate self-similarly, consistent with a range of kinematic models that have been used to describe them. Additionally, we observed that uplift has contributions both from rigid translation along a dipping fault and folding, and that the values observed for many natural structures lie between those predicted by the trishear and kink-style models, such as fixed-axis and constant-thickness fault-propagation folding. Finally, we found that fault-propagation folds exhibit a range of fault dips, with many structures having fault dips coincident with those characteristic of fault-bend folds, while another group is characterized by significantly higher fault dips. By developing a series of discrete-element mechanical models, we found that mechanical layering plays a first-order role in the development of different styles of fault-propagation folding. Homogeneous materials produce trishear-like fault-propagation folds, while strongly layered materials produce structures more similar to the kink-style kinematic models. Comparison with the observations from natural structures indicates that these mechanical models reproduce the observed trends, and that most natural structures fall between these two styles of models. This suggests that trishear and the kink-style (fixed-axis and constant-thickness) fault-propagation folding models may be thought of as end members on a continuum of possible fault-propagation folding geometries that are largely dictated by the degree of mechanical layer anisotropy in the stratigraphy. Finally, we suggest that fault steepening in highly anisotropic models may develop due to strain localization in tightly folded structural forelimbs.
• Hughes, A. N., & Shaw, J. H. (2014). Fault displacement-distance relationships as indicators of contractional fault-related folding style. AAPG Bulletin, 98(2), 227-251. doi:10.1306/05311312006
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  We present a method of using fault displacement-distance profiles to distinguish fault-bend, shear fault-bend, and fault-propagation folds, and use these insights to guide balanced and retrodeformable interpretations of these structures. We first describe the displacement profiles associated with different end-member fault-related folding models, then provide examples of structures that are consistent with these model-based predictions. Natural examples are imaged in high-resolution two- and three dimensional seismic reflection data sets from the Niger Delta, Sichuan Basin, Sierras Pampeanas, and Cascadia to record variations in displacement with distance updip along faults (termed displacement-distance profiles). Fault-bend folds exhibit constant displacement along fault segments and changes in displacement associated with bends in faults, shear fault-bend folds demonstrate an increase in displacement through the shearing interval, and fault-propagation folds exhibit decreasing displacement toward the fault tip. More complex structures are then investigated using this method, demonstrating that displacement-distance profiles can be used to provide insight into structures that involve multiple fault-related folding processes or have changed kinematic behavior over time. These interpretations are supported by comparison with the kinematics inferred from the geometry of growth strata overlying these structures. Collectively, these analyses illustrate that the displacement-distance approach can provide valuable insights into the styles of fault-related folding.
• Hughes, A. N., Benesh, N. P., & Shaw, J. H. (2014). Factors that control the development of fault-bend versus fault-propagation folds: Insights from mechanical models based on the discrete element method (DEM). Journal of Structural Geology, 68, 121-141. doi:10.1016/j.jsg.2014.09.009
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  Abstract We investigate the role and relative importance of a range of geometric and mechanical factors in the development of contractional fault-related folds, with an emphasis on defining the factors that promote the development of fault-bend and fault-propagation folds. We construct a series of discrete-element mechanical models in order to test the effects of fault dip, bulk material strength, mechanical layer anisotropy and spacing, sedimentation rate, and boundary conditions on the style of fault-related fold that develops. We find that fault-bend folding is most favored at low fault ramp dips, with thinly-spaced mechanical layers, and strong layer strength contrasts. In contrast, conditions that inhibit slip on a potential upper detachment surface, such as increased friction and a fixed foreland boundary, encourage the development of fault-propagation folds. Additionally, steeper fault dips, more widely-spaced mechanical layers, and decreased layer strength contrast favor the increased localization of shear during the growth of structures. This leads to structures that deform by a mixture of fault-bend and fault-propagation folding styles. Observations of the distortional strains that develop in the model provide insight into the relationship between the different deformation mechanisms, such as flexural slip and localized shear, which accommodate structural growth and ultimately determine fault-related folding style. Thus, these models provide a context for understanding how rock and fault properties influence whether structures evolve as fault-bend or fault-propagation folds, or as combinations of these end members. We apply these insights to interpret two natural examples from the offshore Niger Delta outer fold-and-thrust belt that exhibit changes in structural style through time as a result of changes in fault properties and syntectonic sedimentation.
• Warren, L. M., Silver, P. G., & Hughes, A. N. (2007). Earthquake mechanics and deformation in the Tonga‐Kermadec subduction zone from fault plane orientations of intermediate‐ and deep‐focus earthquakes. Journal of Geophysical Research, 112(B5). doi:10.1029/2006jb004677
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  [1] We make use of rupture directivity to analyze 82 deep earthquakes (≥100 km depth) in the Tonga-Kermadec subduction zone. Identifying the fault planes for 25 of them, we are able to place new constraints on both the physical mechanism of intermediate- and deep-focus earthquakes and deformation within the subducting slab. We find that half of deep earthquakes with MW ≥ 6 have detectable directivity. We compare the obtained fault orientations with those expected for the reactivation of outer-rise normal faults and with those expected for the creation of new faults in response to the ambient stress field. Earthquakes >300 km depth match the patterns expected for the creation of a new system of faults: we observe both subhorizontal and subvertical fault planes consistent with a downdip-compressional stress field. Slip along these faults causes the slab to thicken. Rupture propagation shows no systematic directional pattern. In contrast, at intermediate depths (100–300 km), all ruptures propagate subhorizontally and all identified fault planes, whether in the upper or lower region of the double seismic zone, are subhorizontal. Rupture propagation tends to be directed away from the top surface of the slab. After accounting for the angle of subduction, the subhorizontal fault plane orientation is inconsistent with the orientation of outer-rise normal faults, allowing us to rule out mechanisms that require the reactivation of these large surface faults. Subhorizontal faults are consistent with only one of the two failure planes expected from the slab stress field, suggesting that isobaric rupture processes or preexisting slab structures may also influence the fault plane orientation. If all deformation takes place on these subhorizontal faults, it would cause the slab to thin. Assuming the slab is incompressible, this implies that the slab is also lengthening and suggests that slab pull rather than unbending is the primary force controlling slab seismicity at intermediate depths.

Proceedings Publications

• Iqbal, O., Hughes, A. N., & Busetti, S. (2023). Comparison of Observed and Modeled Fractures Under Variable Paleostress Conditions, Lisbon Valley, Paradox Basin, Utah. In SEG International Exposition and Annual Meeting.
• Kiser, E. D., Kehoe, H., Chen, M., & Hughes, A. N. (2020). Conjugate Faulting, Lower Mantle Seismicity and Slab Settling Associated with the 2015 Bonin Islands Deep-Focus Earthquake. In American Geophysical Union Annual Meeting, S035-0003.
• Iqbal, O., Padmanabhan, E., Hughes, A., Abdulkareem, F. A., Rabe, C., & Mumtaz, M. (2022). The competitive adsorption of CO₂ and CH₄ and pore structure characterization: Implication for enhanced gas recovery and carbon sequestration. In American Association of Petroleum Geologists Abstracts with Programs.
• Reeher, L. J., Busetti, S., & Hughes, A. (2022). Field Evidence and Elastic Dislocation Modeling of Stress Field Alteration in the Rock Mass Adjacent to Salt. In American Rock Mechanics Association Annual Meeting.
• Runyon, B., Hughes, A. N., List, D. F., Szymanski, E., Vanden Berg, M. D., & Jagniecki, E. (2022). Variations in shortening styles as a function of mechanical stratigraphy inferred from 3D seismic reflection data, northern Paradox Basin, UT. In SEG International Exposition and Annual Meeting, D011S169R003.
• Hanagan, C., Bennett, R., Chiraluce, L., & Hughes, A. N. (2021). Re-evaluation of the Role of Static Stress Triggering for Aftershocks in Italy and California Considering Receiver Plane Uncertainty. In American Geophysical Union Annual Meeting, T55D-0102.
• Reeher, L. J., Hughes, A. N., Davis, G. H., & Rahl, J. (2021). Deciphering Laramide Stress States Across the Colorado Plateau. In American Geophysical Union Annual Meeting, T55D-0101.
• Hughes, A. N., & Connors, C. D. (2020). Comparisons of mechanical and kinematic models of fold-and-thrust belt structures. In American Geophysical Union Annual Meeting, T045-01.
• Connors, C. D., & Hughes, A. N. (2019).

  Flexible Approaches to Kinematic Forward Modeling of Fault-bend Folding

  . In Geological Society of America Annual Meeting.
• Connors, C. D., & Hughes, A. N. (2019).

  Relaxed Kinematic Fault-bend Folding Constraints Informed by Mechanical Modeling

  . In Geological Society of America Annual Meeting.
• Hughes, A. N., Reeher, L., Krantz, R. W., Lingrey, S., Davis, G. H., & Person, M. (2019).

  Stress Field Variability Around Salt Structures Evaluated Through a Comparison of Natural Fracture Sets with Mechanical Models, Paradox Basin, Utah

  . In Geological Society of America Annual Meeting.
• Lucero, D., Person, M., Hughes, A. N., Reiners, P. W., & Barton, M. D. (2019). Influence of Internal Fluid Generation Mechanisms on Copper Mineralization In the Lisbon Valley, Paradox Basin, Utah. In Geological Society of America Abstracts with Programs.
• Person, M., Mcintosh, J. C., Ferguson, G., Lucero, D., Krantz, R. W., Lingrey, S., Hughes, A. N., Reiners, P. W., Thorson, J. P., & Barton, M. D. (2019). Hydrologic Constraints On Lisbon Valley Copper Mineralization within the Paradox Basin, Utah. In Geological Society of America Abstracts with Programs.
• Reeher, L., Davis, G. H., Hughes, A. N., Streeter, D., & Julius, C. (2019).

  Mechanical Characterization and Failure Development within Jurassic Sandstones Proximate to Salt Structures, Paradox Basin, Southern UT

  . In Geological Society of America Annual Meeting.
• Reeher, L., Hughes, A. N., & Davis, G. H. (2019). Laramide Deformation on the Colorado Plateau Analyzed through Integrated Structural Techniques. In Geological Society of America Abstracts with Programs.
• Reiners, P. W., Barton, I. F., Barton, M. D., Davis, G. H., Kirk, J. M., Krantz, R. W., Hughes, A. N., Mcintosh, J. C., Person, M., & Thorson, J. P. (2019). Evolution of the Paradox Basin Subsurface Fluid-Flow System and Paleofluid-Rock Reaction Products. In Geological Society of America Abstracts with Programs.
• Hughes, A. N., & Favorito, D. (2018). Empirical Observations and Mechanical Implications of Fault Displacement Vectors within a Complex Fault System in the Taranaki Basin, New Zealand. In American Geophysical Union Annual Conference.
• Hughes, A. N. (2017). Investigations into the Mechanics and Kinematics of Extensional Fault Systems. In American Association of Petroleum Geologists Annual Convention.
• Hughes, A. N. (2017). Mechanical Constraints on Fault Geometries and Structural Styles in Extensional Geologic Settings. In American Geophysical Union Annual Conference.
• Hughes, A. N., & Shaw, J. H. (2016).

  Investigating the Impact of Mechanical Properties on Contractional Fault-related Folding Style through Discrete Element Modeling

  . In Geological Society of America Annual Meeting.