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Articles 1 - 5 of 5

Full-Text Articles in Geology

The Evolution Of Billfish, Andrew Blitman Dec 2013

The Evolution Of Billfish, Andrew Blitman

Andrew Blitman

No abstract provided.


Sharks Of The Devonian, Andrew Blitman Dec 2011

Sharks Of The Devonian, Andrew Blitman

Andrew Blitman

No abstract provided.


Reverse Drag Revisited: Why Footwall Deformation May Be The Key To Inferring Listric Fault Geometry, Phillip G. Resor, David D. Pollard Dec 2011

Reverse Drag Revisited: Why Footwall Deformation May Be The Key To Inferring Listric Fault Geometry, Phillip G. Resor, David D. Pollard

Phillip G Resor

Although reverse drag, the down warping of hanging wall strata toward a normal fault, is widely accepted as an indicator of listric fault geometry, previous studies have shown that similar folding may form in response to slip on faults of finite vertical extent with listric or planar geometry. In this study we therefore seek more general criteria for inferring subsurface fault geometry from observations of near-surface deformation by directly comparing patterns of displacement, stress, and strain around planar and listric faults, as predicted by elastic boundary element models. In agreement with previous work, we find that models with finite planar, …


Forward Modeling Synsedimentary Deformation Associated With A Prograding Steep-Sloped Carbonate Margin, Phillip G. Resor Dec 2009

Forward Modeling Synsedimentary Deformation Associated With A Prograding Steep-Sloped Carbonate Margin, Phillip G. Resor

Phillip G Resor

Differential compaction associated with prograding and aggrading steep-rimmed carbonate margins leads to penecontemporaneous and post- depositional modifications of stratal geometries and tensile and shear stress concentrations that result in brittle deformation. In an effort to investigate controls on these deformation processes, we employ a step-wise gravity loaded elastic model that captures pre-failure displacement and stress field patterns for a depositional geometry based on the Permian Capitan depositional system, Guadalupe Mountains, West Texas and New Mexico, USA. We consider four model geometries with varying progradation to aggradation (P/A) ratio, from strongly prograding (P/A=10) to strongly aggrading (P/A=0.1). The strongly prograding case …


Slip Heterogeneity On A Corrugated Fault, Phillip G. Resor, Vanessa E. Meer Dec 2008

Slip Heterogeneity On A Corrugated Fault, Phillip G. Resor, Vanessa E. Meer

Phillip G Resor

Slip heterogeneity reflects the fundamental physics of earthquake rupture and has been attributed to strong fault patches termed asperities or barriers. We propose that variations in fault-surface orientation due to slip-parallel corrugations may act as geometric asperities and barriers, generating variations in incremental (i.e. due to a single earthquake) slip across a fault surface. We evaluate this hypothesis using observations from the Arkitsa normal fault exposure in central Greece. A scan of the Arkitsa fault surface with 1-m spatial resolution and mm-scale precision reveals corrugations made up of 1–5 m wide synforms, antiforms, and nearly planar fault sections with long …