Compositional changes in Trans-Pecos Texas Magmatism Coincident with Cenozoic stress realignment

Early Basin and Range Development in Trans-pecos Texas and Ad3acent Chihuahua: Magmatism and Orientation, Timing, and Style of Extension

Magmatism during early Basin and Range extension in Trans-Pecos Texas consisted of widespread but volumetrically minor alkali basalts (24-17 Ma), an alkalic mafic to intermediate composition stratovolcano (28-27 Ma), and a dominantly rhyolitic, possibly bimodal, caldera complex in adjacent Chihuahua (3128 Ma). This magmatism contrasted sharply with the much more voluminous and compositionally m...

Chromosome numbers in Chihuahuan Desert Cactaceae. III. Trans-Pecos Texas.

Chromosome numbers are reported for 112 collections of Cactaceae, including 102 collections of Opuntia. Reports are presented for 33 species in five genera and a total of 36 taxa. Two specimens were sterile. Emphasis was given to the documentation of intraspecific ploidy-level consistencies and differences, because of the current poor state of knowledge about the populational integrity of chrom...

Predation of Big Game and Livestock in the Texas Trans-pecos

Predation of livestock and big game remains a matter of concern for ranch managers and operators in the Trans-Pecos. Current evidence indicates that mountain lions (Felis concolor), bobcats {Lynx rufus), and coyotes (Canis latrans) are the primary predators involved, although little information is available on bobcats. A gradual shift from sheep to cattle management has resulted in a correspond...

Regional groundwater flow paths in Trans-Pecos, Texas inferred from oxygen, hydrogen, and strontium isotopes

r a 200 .015 : +1 570 qu.edu Summary Stable isotopes, radiogenic isotopes, and major ion chemistry are used to constrain flow paths in a fracture-controlled regional groundwater flow system in far west Texas. The flow system occurs in Permian and Cretaceous sedimentary rocks and Cenozoic alluvial basin fill. Samples from springs and wells in the study area were analyzed for major ions and hydro...

Compositional Diversity of Late Cenozoic Basalts in a Transect Across the Southern Washington Cascades: Implications for Subduction Zone Magmatism