Browsing by Subject "Trans-Pecos"
Now showing 1 - 8 of 8
- Results Per Page
- Sort Options
Item Addressing the Interconnected Issues of Energy Sprawl(The University of Texas at Austin, 2018-08-22) Young, MichealItem Data Collection Plan For Geological Remote Sensing in the Volcanic Terrain of Trans-Pecos Texas, ASVT Test Site 5(1980) Finley, Robert J.; Baumgardner, Jr., Robert W.This document describes a ground and aircraft data collection plan to be carried out as part of the Texas Applications System Verification and Transfer (ASVT) Project, which is a joint effort of the Texas Natural Resources Information System (TNRIS) Task Force and the National Aeronautics and Space Administration (NASA). The Texas Department of Water Resources/TNRIS has contracted with the Bureau of Economic Geology for the preparation of this Data Collection Plan (DCP), to be initially implemented during the period June-August 1980 as described herein. This DCP applies to a test site in the Trans-Pecos region of Texas, one of five designated test sites within the state. Previously, a ground data collection plan had been prepared for the coastal test site (Finley, 1978), and a plan is in preparation for the High Plains test site.Item Delineation of the ground-water flow systems of the Eagle Flat and Red Light Basins of Trans-Pecos Texas(1997) Darling, Bruce Kelley, 1951-; Sharp, John Malcolm, Jr., 1944-The hydrogeologic systems of the Eagle Flat and Red Light basins of Trans-Pecos are characterized by three-dimensional flow components, fracture and double-porosity flow, hydrochemically zoned water in alternating permeable and low-permeability rocks and poorly consolidated strata, and areal transitions between unconfined, confined, and leaky-confined aquifers. Ground-water depths greater than 900 ft (275 m) beneath the topographically lowest areas of the Eagle Flat Basin, along with closed potentiometric contours suggest drainage to a regional flow system that transports ground water beyond basin boundaries, probably beneath the Devil Ridge ground-water divide and the thick Tertiary basin fill deposits of the Red Light Basin, where hydraulic head along the Rio Grande is as much as 400 ft (122 m) below the lowest point of the potentiometric surface in the Eagle Flat Basin. Radiocarbon is unreliable as estimator of absolute age. This is attributable to contributions of dead carbon by the dissolution of carbonate rocks and/or to isotope exchange. Mixing with younger (tritiated) ground waters adds to the complexity. δ¹⁸O values of the apparently oldest ground waters, however, are about 3%₀ (SMOW) lower than those of demonstrably modem ground waters. This pattern is thought to be consistent with the influence of precipitation under an older and probably cooler climatic regime. This suggests that the oldest ground waters may have late Pleistocene recharge dates (e.g., 10,000 to 20,000 years). In addition, the temperature-fractionation gradient for δ¹⁸O suggests precipitation under climatic conditions that were from 5.5 to 7.3°C below those of average Holocene values. Isotopic data indicate that major recharge areas are focused in the upper elevations of the mountains and along mountain fronts. Recharge attributable to precipitation does not occur in the flats and draws, except where shallow water-table conditions exist in alluvial deposits adjacent to the Rio Grande. Low-permeability late-stage calcic soils limit the potential for precipitation recharge across the broad alluvial fans of the Eagle Mountains and the Indio Mountains. Estimates of precipitation recharge derived from a numerical flow model are about 0.07 in per year, or about 14% of estimates by the U.S. Geological SurveyItem Letter to H.B. Stenzel from L.G. Ragsdale on 1928-09-23(1928-09-23) Ragsdale, L.G.Item A New Genus of Eomyid Rodent from the Ogliocene Ash Spring Local Fauna of Trans-Pecos Texas(Texas Memorial Museum, The University of Texas at Austin, 1969-02) Harris, John M.; Wood, Albert E.This paper describes a new genus and species of eomyid rodent, Meliakrouniomijs tcilsoni, from the Ash Spring local fauna, the latest vertebrate faunule from the Vieja Group of Trans-Pecos Texas. The teeth indicate that it is an eomyid rodent in process of tooth pattern simplification. Resemblances in tooth pattern and jaw structure to heteromyids and eomyids suggest that Meliakrouniomys may represent a transitional stage between the two families.Item Structural evolution and metamorphism of mid-Proterozoic basement in the northwest Van Horn Mountains, Trans-Pecos, Texas(1987) Bristol, David Arthur, 1961-; Mosher, Sharon, 1951-Psammitic, pelitic and mafic schists in a NNW-trending horst in the NW Van Horn Mountains of west Texas show evidence of a multiphase, synmetamorphic, ductile Grenville-age deformation. Other basement exposures in the Van Horn area record a later phase of Grenville-age brittle deformation that has wholly or partly obscured the earlier-formed ductile features. Detailed mapping indicates that basement rocks exposed in the NW Van Horn Mountains underwent three phases of progressive isoclinal folding followed by two later, less intense, nearly coaxial folding episodes. The second phase of folding produced the dominant foliation and foliation intersection (S₁/S₂) lineation observed throughout the area. This deformation is inferred to have resulted from a large scale folding event, at or very near, peak metamorphic conditions, possibly associated with nappe formation. Garnet-biotite and garnet-hornblende Fe-Mg exchange thermometry indicate maximum temperatures of 640±50°C, corresponding to mid-amphibolite facies conditions, for this event. The intrusion of late syn- to post-orogenic pegmatite sills and dikes was widespread across the area. The associated pegmatitic fluids either facilitated or became the principal catalysts of a static recrystallization event. This event altered previously formed deformational fabrics and produced diagnostic strain-free textures in many minerals. The Grenville-age, polydeformational history recorded by the basement rocks of the NW Van Horn Mountains is similar to that noted in portions of the Llano Uplift of central Texas, about 650 km to the east. The strong similarity of deformational styles in these two areas suggests that large-scale folds with localized shear zones were produced in this region of the Grenville ProvinceItem Test Plan for Remote Sensing Information Subsystem Products Test Site 2 and 5 (High Plains and Trans-Pecos Texas)(1981) Finley, Robert J.; Baumgardner, Jr., Robert W.This plan outlines the map products to be generated from Landsat imagery, airborne multispectral scanner imagery, and aerial photography of test sites in the High Plains of the Texas Panhandle and in Trans-Pecos Texas. The objectives of producing these maps are: To determine the methodology necessary for developing each type of product. To designate the size, scale, level of detail, and final format of each map within an initial phase of development of remote sensing products. The map products and data analysis procedures described here are based on: Objectives outlined in the Applications System Verification and Transfer (ASVT) Project Plan (McCulloch and McKain, 1978). State agency information needs and listings of possible products developed in conjunction with the User Advisory Group. The Remote Sensing Information Subsystem (RSIS) Level I Design and Design Review documents. The descriptions contained herein are primarily conceptual and are derived from limited hands-on experience with Landsat imagery and digital image processing hardware and software. Analysis of the High Plains region will make maximum use of experience gained in the coastal test site using ISOCLS for unsupervised classification of land cover/land use. The image enhancement techniques to be used for geologic applications in the Trans-Pecos region have not previously been applied as part of RSIS.Item (Vol. 09, 2006-12) Species Of Philadelphus (Hydrangeaceae) From Trans-Pecos Texas(2006-12) Turner, Billie L.Three species of Philadelphus are accepted as occurring in Trans-Pecos, Texas: P. mearnsii, P. microphyllus, and P. serpyllifolius. Philadelphus mearnsii is known only from Culberson and El Paso counties; P. microphyllus and P. serpyllifolius are more widespread. Philadelphus microphyllus is treated as having three intergrading varieties: Philadelphus microphyllus var. argenteus, P. m. var. crinitus (C. L. Hitchc.) B. L. Turner, and P. m. var. microphyllus. Philadelphus serpyllifolius is treated as having two intergrading varieties: Philadelphus serpyllifolius var. intermedius B.L. Turner, and P. s. var. serpyllifolius. Maps showing their distributions in the area concerned are provided.