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A taxonomic and anatomic assessment of the extinct Zygodactylidae (Aves) from the Green River Formation of Wyoming and placement of Zygodactylidae within Aves
(2012-05)
Birds are the most diverse extant group of terrestrial vertebrates, and relationships amongst major extant and extinct avian lineages remain hotly debated. A clade of Aves which has received limited attention is the extinct ...
The use of δ]¹³C values of leporid teeth as indicators of past vegetation
(2013-05)
Records of change of [delta]13C values in vertebrate teeth offer an opportunity to gain insight into changes in past vegetation. Increasingly, teeth from small mammals are used for such purposes, but because their teeth ...
Developing a flash drought indicator for the US Great Plains
(2013-05)
Flash droughts refer to those droughts that intensify rapidly in spring and summer, coupled with a strong increase in summer extreme temperatures, such as those that occurred over Texas in 2011 and the Great Plains in 2012. ...
Hydrogeological analysis of groundwater chemistry and sulfate distribution, Blanco and Hays Counties, Texas
(2010-05)
High concentrations of sulfate in groundwater, up to ten times the amount recommended by the EPA, in Blanco and Hays Counties, Texas, are of concern as groundwater pumping and population increase. The goals of this study ...
Stratigraphic architecture, depositional systems, and lithofacies of the Mississippian upper Barnett Two-Finger Sand, Midland Basin, Texas
(2018-01-25)
The upper Barnett Two Finger Sand in West Texas forms oil and gas reservoirs that produce from natural fractures and low-permeability intraparticle matrix nano- to micropores. The section contains two mixed silt- to very ...
The seismic response to fracture clustering : a finite element wave propagation study
(2014-05)
Characterizing natural and man-made fracture networks is fundamental to predicting the storage capacity and pathways for flow of both carbonate and shale reservoirs. The goal of this study is to determine the seismic ...
Paleogene sedimentation patterns and basin evolution during Andean orogenesis, Middle Magdalena Valley basin, Colombia
(2010-08)
The Central Cordillera and Eastern Cordillera of the northern Andes form the western and eastern flanks of the north-trending Middle Magdalena Valley basin. Previous estimates for the timing of initial exhumation of the ...
Paleogeographic evolution during the Eocene Upper Wilcox in the Houston embayment with consideration of the Yoakum Canyon fill
(2015-05)
The Eocene Upper Wilcox clastic wedge represents the second major pulse of terrigenous material into the Gulf of Mexico basin. Recent interest in the Wilcox has been reinvigorated by the drilling of the Baha prospect in ...
Geochemical and isotopic tracing of Paleozoic groundwater flow in breached anticlines : a case study at Lower Kane Cave, Bighorn Basin, Wyoming
(2004-08-16)
Lower Kane Cave is forming in the upper Mississippian Madison Limestone by sulfuric acid speleogenesis. The cave is located along the axialtrace of the Little Sheep Mountain anticline where the Paleozoic units have been ...
Single-crystal elasticity of the lower-mantle ferropericlase (Mg0.92Fe0.08)O
(2014-05)
This study focuses on investigating the effect of the electronic spin transition of iron on the elasticity of the candidate lower mantle ferropericlase (Mg,Fe)O. This may be relevant to our understanding of the seismic ...