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Articles 1 - 12 of 12

Full-Text Articles in Geology

San Andreas Structural Interpretation: Merging Geophysical And Geological Data At Safod And Vicinity, Rebekah E. Wood, James P. Evans, Peter E. Malin Nov 2010

San Andreas Structural Interpretation: Merging Geophysical And Geological Data At Safod And Vicinity, Rebekah E. Wood, James P. Evans, Peter E. Malin

Rebekah Wood

No abstract provided.


Late Quaternary Distribution And Biogeography Of The Southern Lake Eyre Basin (Sleb) Megafauna, South Australia, Steve Webb Aug 2010

Late Quaternary Distribution And Biogeography Of The Southern Lake Eyre Basin (Sleb) Megafauna, South Australia, Steve Webb

Steve Webb

Understanding the population demography, species distribution and biogeography of Australia’s megafauna is essential for understanding their extinction. This process is only just beginning, and this article discusses these aspects while concentrating on a particular region; the southern Lake Eyre Basin (SLEB). It is also the first detailed description of the distribution of megafauna across that region of central Australia. The data are based on an extensive longitudinal study of 41 palaeontological sites spread across 250 000km2. Megafauna adaptation and response to extensive environmental change during the late Quaternary is reflected in the composition and distribution of 21 megafauna species found …


Evolution Of The Kangmar Dome, Southern Tibet: Structural, Petrologic, And Thermochronologic Constraints, Jeffrey Lee, Bradley Hacker, William Dinklage, Yu Wang, Phillip Gans, Andrew Calvert, Ann Blythe, William Mcclelland Jul 2010

Evolution Of The Kangmar Dome, Southern Tibet: Structural, Petrologic, And Thermochronologic Constraints, Jeffrey Lee, Bradley Hacker, William Dinklage, Yu Wang, Phillip Gans, Andrew Calvert, Ann Blythe, William Mcclelland

Ann Blythe

Structural, thermobarometric, and thermochronologic investigations of the Kangmar Dome, southern Tibet, suggest that both extensional and contractional deformational histories are preserved within the dome. The dome is cored by an orthogneiss which is mantled by staurolite + kyanite zone metasedimentary rocks; metamorphic grade dies out up section and is defined by a series of concentric kyanite-in, staurolite-in, garnet-in, and chloritoid-in isograds. Three major deformational events, two older penetrative events and a younger doming event, are preserved. The oldest event, D1, resulted in approximately E-W trending tight to isoclinal folds of bedding with an associated moderately to steeply north dipping axial …


Cenozoic Mass Extinctions In The Deep Sea; What Disturbs The Largest Habitat On Earth?, Ellen Thomas Feb 2010

Cenozoic Mass Extinctions In The Deep Sea; What Disturbs The Largest Habitat On Earth?, Ellen Thomas

Ellen Thomas

No abstract provided.


Collaborative Research: Graptolite Biogeography, Paleo-Gis, And Evolutionary Dynamics Of Early Paleozoic Zooplankton, Daniel Goldman Dec 2009

Collaborative Research: Graptolite Biogeography, Paleo-Gis, And Evolutionary Dynamics Of Early Paleozoic Zooplankton, Daniel Goldman

Daniel Goldman

Funding Agency: National Service Foundation Investigators: Dr. Goldman, SY. Wu Amount: $255,326.00 Number of years: 4 years


Deformation Of Continental Crust Along A Transform Boundary, Coast Mountains, British Columbia, Scott Bogue, Margaret Rusmore, Karen Dodson, Kenneth Farley, Glenn Woodsworth Dec 2009

Deformation Of Continental Crust Along A Transform Boundary, Coast Mountains, British Columbia, Scott Bogue, Margaret Rusmore, Karen Dodson, Kenneth Farley, Glenn Woodsworth

Scott Bogue

New structural, paleomagnetic, and apatite (U-Th)/He results from the continental margin inboard of the Queen Charlotte fault (∼54°N) delineate patterns of brittle faulting linked to transform development since ∼50 Ma. In the core of the orogen, ∼250 km from the transform, north striking, dip-slip brittle faults and vertical axis rotation of large crustal domains occurred after ∼50 Ma and before intrusion of mafic dikes at 20 Ma. By 20 Ma, dextral faulting was active in the core of the orogen, but extension had migrated toward the transform, continuing there until <9 Ma. Local tilting in the core of the orogen …


Faculty Spotlight: Mark Sutherland, Mark Sutherland Dec 2009

Faculty Spotlight: Mark Sutherland, Mark Sutherland

Mark Sutherland

Interview with Mark J. Sutherland about his earth science teaching career at College of DuPage.


Very Rapid Geomagnetic Field Change Recorded By The Partial Remagnetization Of A Lava Flow, Scott Bogue, Jonathan Glen Dec 2009

Very Rapid Geomagnetic Field Change Recorded By The Partial Remagnetization Of A Lava Flow, Scott Bogue, Jonathan Glen

Scott Bogue

A new paleomagnetic result from a lava flow with a distinctive, two-part remanence reinforces the controversial hypothesis that geomagnetic change during a polarity reversal can be much faster than normal. The 3.9-m-thick lava (“Flow 20”) is exposed in the Sheep Creek Range (north central Nevada) and was erupted during a reverse-to-normal (R-N) geomagnetic polarity switch at 15.6 Ma. Flow 20 began to acquire a primary thermoremanence while the field was pointing east and down but was soon buried, reheated, and partially-remagnetized in a north-down direction by the 8.2-m-thick flow that succeeded it. A simple conductive cooling calculation shows that the …


Fabric Development In Cm-Scale Shear Zones In Ultramafic Rocks, Red Hills, New Zealand, Caroline Webber, Julie Newman, Caleb Holyoke, Timothy Little, Basil Tikoff Dec 2009

Fabric Development In Cm-Scale Shear Zones In Ultramafic Rocks, Red Hills, New Zealand, Caroline Webber, Julie Newman, Caleb Holyoke, Timothy Little, Basil Tikoff

Caleb Holyoke

No abstract provided.


Accurate Differential Stress Measurement Using The Molten Salt Cell And Solid Salt Assemblies In The Griggs Apparatus With Applications To Strength, Piezometers And Rheology, Caleb Holyoke, Andreas Kronenberg Dec 2009

Accurate Differential Stress Measurement Using The Molten Salt Cell And Solid Salt Assemblies In The Griggs Apparatus With Applications To Strength, Piezometers And Rheology, Caleb Holyoke, Andreas Kronenberg

Caleb Holyoke

No abstract provided.


Deformation Of Single Crystal Sample Using D-Dia Apparatus Coupled With Synchrotron X-Rays: In-Situ Stress And Strain Measurements At High Pressure And Temperature, Jennifer Girard, Jiuhua Chen, Paul Raterron, Caleb Holyoke Dec 2009

Deformation Of Single Crystal Sample Using D-Dia Apparatus Coupled With Synchrotron X-Rays: In-Situ Stress And Strain Measurements At High Pressure And Temperature, Jennifer Girard, Jiuhua Chen, Paul Raterron, Caleb Holyoke

Caleb Holyoke

No abstract provided.


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 …