Geology Commons^™

Geophysical Constraints On The Hueco And Mesilla Bolsons: Structure And Geometry, Victor Manuel Avila

Open Access Theses & Dissertations

The Hueco and Mesilla Bolsons are part of the intramountain basins of the Rio Grande Rift system. These bolsons are the primary source of groundwater for the El Paso-Ciudad Juarez metropolitan area and contain faults that show evidence of repeated earthquakes during the Quaternary. The region is also associated with has low-level (M<4) seismicity. The collection and analysis of precision gravity data, coupled with information from water wells, multichannel analysis of surface waves (MASW) studies and previously published seismic reflection lines, have been used to examine the structure and faulting within these bolson. This study reveals that the Hueco and Mesilla Bolsons are very different structurally. The southern Mesilla Bolson contains about 500 m of sediment. Faults are difficult to trace and have less than 50-100 m of displacement across them. The southernmost bolson contains numerous Tertiary intrusions and the thickness of Cretaceous bedrock appears to decrease from south to north, possibly delineating the edge of Laramide age deformation within the bolson. The northern Hueco Bolson contains 1800 to 2500 m of basin fill. Displacement along the East Franklin Mountains fault (EFMF), a fault with evidence for repeated earthquakes within the past 64,000 years, is about 1500 m, and displacement on intrabasin faults is 200-300 m. Several intrabasin faults appear to control the saline to freshwater contact within the bolson. The EFMF may extend over 30 km south of the end of its mapped trace at the end of the Franklin Mountains and a number of intrabasin faults also extend south into the urbanized regions of the study area. The EFMF and other basin structures appear to be offset or disrupted at the speculated edge of Laramide deformation that lies beneath the bolson. Horizontal Gradient Methods (HGM) were applied to the gravity data and were successful for tracing faults and older Laramide features within the Hueco Bolson beneath the urbanized regions of the cities. HGM were not as successful at tracing faults within the Mesilla Bolson, however they were helpful for tracing the subsurface extent of igneous intrusions including the Mt. Cristo Rey, River, Three Sisters, and the Westerner outcrops. Some of these features appear linked at depth by a series of dikes and faults. MASW data were used to determine the average shear wave velocity in the upper 30m (Vs 30) at ~70 sites within the Hueco Bolson. These observations were combined with similar data collected previously in Juarez to produce regional velocity and site classification maps. The results show low velocities are found close to the river within fluvial deposits with higher velocities close to the Franklin Mountains where bedrock is close to the surface and higher velocities in upland regions of northeast El Paso were soils appear to be more highly cemented. These data will be used in conjunction with information on bolson geometries to model the expected effects of strong ground motion from earthquakes in the El Paso-Ciudad Juarez region.

Sedimentologic And Stratigraphic Analysis Of Synrift Siliciclastic Fluvial And Lacustrine Strata In The Lower Cretaceous Upper Yucca Formation, Indio Mountains, West Texas, Matthew Robert Fox

Open Access Theses & Dissertations

Outcrops of the upper Yucca Formation in the Indio Mountains near Van Horn, Texas provide temporal, tectonic, and climatic similarities to Lower Cretaceous, synrift, greenhouse pre-salt lacustrine strata along in the subsurface of the South Atlantic margin. These "pre-salt" strata hold prolific petroleum reservoirs but despite extensive seismic studies performed for regional scale hydrocarbon exploration in these lacustrine reservoirs, sedimentologic and stratigraphic analyses have rarely been published. The Upper Yucca Formation in the Indio Mountains contain lacustrine reservoir analogs that intertongue with fluvial and deltaic sandstones. Near Squaw Canyon, fluvial-deltaic sandstones are reduced in abundance to lacustrine carbonates by nearly …

New Hampshire Beaches: Sediment Characterization, Larry G. Ward, Kaitlyn A. Mcpherran, Zachary S. Mcavoy, Maxlimer Coromoto Vallee-Anziani

Center for Coastal and Ocean Mapping

The grain size of the natural sediment composing the major New Hampshire beaches under summer equilibrium conditions was determined as a first step in assessing the optimal sediment size that would be needed for beach nourishment. In summer, 2015, seven major beaches including Wallis Sands, Foss Beach, Jenness Beach, North Hampton Beach, North Beach, Hampton Beach, and Seabrook Beach were sampled along three to five transects extending from the dunes or engineering structures (e.g., seawalls) to the low water line. In addition, the beach cross-section was profiled using a rover GPS system or the Emery method (profile rods and the …

Utilization Of Satellite-Derived Salinity For Enso Studies And Climate Indices, Caroline Mary Corbett

Theses and Dissertations

Conventionally, El Niño-Southern Oscillation (ENSO) is studied using sea surface temperature (SST) observations in the central and eastern equatorial Pacific Ocean. Recently, sea surface salinity (SSS) in the equatorial Pacific has been studied in relation to the phases of ENSO. Previously, SSS was observed in the equatorial Pacific using the Tropical Ocean Global Atmosphere (TOGA) / Tropical Atmosphere Ocean (TOA), the Argo float network, and Oceanic General Circulation Models (OGCM). The launch of NASA’s Aquarius Salinity Mission and ESA’s Soil Moisture Ocean Salinity (SMOS) opened a new era in which high resolution global near real-time SSS observations are readily available. …

Microstructure And Deformation Mechanism Analysis Of Carbonate Rock Located In An Anticline, Natalie R. Zidd

Williams Honors College, Honors Research Projects

Rock samples were collected from the Tensleep formation in the Seminoe Mountains located in Carbon County, Wyoming. These samples were analyzed to determine the deformation mechanisms operating during small scale displacement faulting. There are three distinct zones included in the sample which includes the undeformed Tensleep, fine grained layers with grain size variation, and porous layers with grain size variation. The microstructures in the fine grained layer were consistent with deformation by crystal plastic deformation mechanisms; whereas, the microstructures in the porous layer were consistent with brittle deformation mechanisms. The microstructures in these rocks are nearly identical to those observed …

The Map Portal Project At The Geological Survey Of Israel, Marcelo Rosensaft, Howard R. Feldman

Lander College for Women - The Anna Ruth and Mark Hasten School Publications and Research

The Geological Survey of Israel is mandated to prepare official geological maps of Israel at different scales. When, by the end of the 80’s, GIS systems became more popular and a realistic option for us, we started the development of a methodology and system that led to the completion of a new geological map of Israel at 1:200,000 in 1998. This resulted in a huge impetus for the preparation of the Geological Map of Israel at 1:50,000 in 79 separate sheets. In addition, using the above GIS system, other maps were prepared; outcomes of various projects - in hydrogeology, geological …

Paleoenvironmental Analysis Of Cretaceous Mudstones At Slope Mountain, Alaska Using Carbon Stable Isotopes, Ashley Ratigan

Honors Papers

This project uses field samples, microfacies analysis, and carbon stable isotopes of mudstones to determine past environmental conditions of North Slope, Alaska during the Albian-Cenomanian (Cretaceous). Samples were taken at Slope Mountain, Alaska located north of the Brooks Range. Slope Mountain includes the Torok Formation and the upper and lower Nanushuk Formations that consist of alluvial, deltaic, and shallow marine facies that were deposited into the North Slope foreland basin on the Arctic Alaska micro plate. An exhaustive search for identifiable microfossils, such as pollen, diatoms, and foraminifera in the samples yielded nothing but charcoal and carbon residue. No other …

An Investigation Of Ams In Oman Ophiolite Gabbros, Sarah D. Trutner

Honors Papers

Crustal accretion processes at mid-ocean ridges are still poorly understood, and several competing models exist that try to explain exactly how magma from the mantle is incorporated into oceanic crust at a crustal spreading center. Ophiolites, or fragments of oceanic crust exposed on land, are useful sites at which to conduct rock fabric studies to understand oceanic crust formation processes. This study focuses on samples of upper foliated gabbros taken from the Oman ophiolite in order to characterize their fabric orientations and contribute to a better model of crustal formation. Much of the focus of this study is on using …

Experimental Investigation Of Fracture Width Limitations Of Granular Lost Circulation Treatments, Mortadha Al-Saba, Runar Nygaard, Arild Saasen, Olav Magnar Nes

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Drilling fluid losses into fractured shales is a major challenge. Lost circulation treatments are widely applied to mitigate the losses; however, the effectiveness of these treatments is affected by different physical properties of the used lost circulation materials (LCM). This paper presents an experimental investigation to study the effect of LCM type, concentration, particle size distribution, temperature, and LCM shape on the formed seal integrity, with respect to differential pressure, at different fracture widths. The overall objective of this study is to address the effectiveness of LCM treatments in sealing fractured shales, with specific application to the over consolidated Barents …

Quantifying Exceptionally Large Populations Of Acropora Spp. Corals Off Belize Using Sub-Meter Satellite Imagery Classification, James Busch, Lisa Greer, David Harbor, Karl Wirth, Halard Lescinsky, H. Allen Curran, Kirsten De Beurs

Geosciences: Faculty Publications

Caribbean coral reefs have experienced dramatic declines in live coral cover in recent decades. Primary branching framework Caribbean corals, Acropora cervicornis (Lamarck, 1816) and Acropora palmata (Lamarck, 1816), have suffered the greatest collapse. Coral Gardens, Belize, is one of few remaining, and perhaps the largest, refugia for abundant, healthy, but undocumented populations of both Acropora species in the Caribbean Sea. In the present study, GeoEye-1 multispectral satellite imagery of a 25 km2 reefal area near Ambergris Caye, Belize, was analyzed to identify live Acropora spp. cover. We used a supervised classification to predict occurrence of areas with live Acropora spp. …

Documentation Of Extensive Root Systems Of Thalassia Seagrass Along The Banks Of Pigeon Creek, San Salvador Island, Bahamas, Bosiljka Glumac, H. Allen Curran

Geosciences: Faculty Publications

Reprinted from: Bosiljka Glumac & Michael Savarese (eds.), Proceedings of the 16th Symposium on the Geology of the Bahamas and Other Carbonate Regions: San Salvador, Gerace Research Center

Modern And Fossil Callianassid Burrows Of The Bahamas: Comparisons And Implications For Paleoenvironmental Analysis, H. Allen Curran, Koji Seike

Geosciences: Faculty Publications

Reprinted from: Bosiljka Glumac & Michael Savarese (eds.), Proceedings of the 16th Symposium on the Geology of the Bahamas and Other Carbonate Regions:San Salvador, Gerace Research Center

Deep Subsurface Drip Irrigation Using Coal-Bed Sodic Water: Part Ii. Geochemistry, Carleton R. Bern, George N. Breit, Richard W. Healy, John W. Zupancic

United States Geological Survey: Staff Publications

Waters with low salinity and high sodium adsorption ratios (SARs) present a challenge to irrigation because they degrade soil structure and infiltration capacity. In the Powder River Basin of Wyoming, such low salinity (electrical conductivity, EC 2.1 mS cm⁻¹) and high-SAR (54) waters are co-produced with coal-bed methane and some are used for subsurface drip irrigation (SDI). The SDI system studied mixes sulfuric acid with irrigation water and applies water year-round via drip tubing buried 92 cm deep. After six years of irrigation, SAR values between 0 and 30 cm depth (0.5–1.2) are only slightly increased over non-irrigated …

Geochemical Evidence For Seasonal Controls On The Transportation Of Holocene Loess, Matanuska Valley, Southern Alaska, Usa, Daniel R. Muhs, James R. Budahn, Gary Skipp, John P. Mcgeehin

United States Geological Survey: Staff Publications

Loess is a widespread Quaternary deposit in Alaska and loess accretion occurs today in some regions, such as the Matanuska Valley. The source of loess in the Matanuska Valley has been debated for more than seven decades, with the Knik River and the Matanuska River, both to the east, being the leading candidates and the Susitna River, to the west, as a less favorable source. We report here new stratigraphic, mineralogic, and geochemical data that test the competing hypotheses of these river sources. Loess thickness data are consistent with previous studies that show that a source or sources lay to …

Retrospective: Adjusting Contaminant Concentrations In Bird Eggs To Account For Moisture And Lipid Loss During Their Incubation, Barnett A. Rattner, Stanley N. Wiemeyer, Lawrence J. Blus

United States Geological Survey: Staff Publications

By the 1960s, research and monitoring efforts on chlorinated

pesticide residues in tissues of wildlife were well

underway in North America and Europe. Conservationists

and natural resource managers were attempting to resolve

whether pesticide exposure and accumulated residues were

related to population declines in several species of predatory

and scavenging birds (e.g., bald eagle Haliaeetus

leucocephalus, peregrine falcon Falco peregrinus, brown

pelican Pelecanus occidentalis and osprey Pandion haliaetus).

The avian egg was a favored sampling matrix even

before the realization that eggshell thinning was linked to

population declines (Ratcliffe 1967; Hickey and Anderson

1968) and that the …

Bioaccessibility Tests Accurately Estimate Bioavailability Of Lead To Quail, W. Nelson Beyer, Nicholas T. Basta, Rufus L. Chaney, Paula F.P. Henry, David E. Mosby, Barnett A. Rattner, Kirk G. Scheckel, Daniel T. Sprague, John S. Weber

United States Geological Survey: Staff Publications

Hazards of soil-borne lead (Pb) to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, the authors measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison with blood Pb concentrations in quail fed a Pb acetate reference diet. Diets containing soil from 5 Pb-contaminated Superfund sites had relative bioavailabilities from 33% to 63%, with a mean of approximately 50%. Treatment of 2 of the soils with phosphorus (P) significantly reduced the bioavailability …

Component Greenhouse Gas Fluxes And Radiative Balance From Two Deltaic Marshes In Louisiana: Pairing Chamber Techniques And Eddy Covariance, Ken W. Krauss, Guerry O. Holm Jr., Brian C. Perez, David E. Mcwhorter, Nicole Cormier, Rebecca F. Moss, Darren J. Johnson, Scott C. Neubauer, Richard C. Raynie

United States Geological Survey: Staff Publications

Coastal marshes take up atmospheric CO₂ while emitting CO₂, CH₄, and N₂O. This ability to sequester carbon (C) is much greater for wetlands on a per area basis than from most ecosystems, facilitating scientific, political, and economic interest in their value as greenhouse gas sinks. However, the greenhouse gas balance of Gulf of Mexico wetlands is particularly understudied. We describe the net ecosystem exchange (NEE_c) of CO₂ and CH₄ using eddy covariance (EC) in comparison with fluxes of CO₂, CH₄, and N₂O using …

Mapping Marginal Croplands Suitable For Cellulosic Feedstock Crops In The Great Plains, United States, Yingxin Gu, Bruce K. Wylie

United States Geological Survey: Staff Publications

Growing cellulosic feedstock crops (e.g., switchgrass) for biofuel is more environmentally sustainable than cornbased ethanol. Specifically, this practice can reduce soil erosion and water quality impairment from pesticides and fertilizer, improve ecosystem services and sustainability (e.g., serve as carbon sinks), and minimize impacts on global food supplies. The main goal of this study was to identify high-risk marginal croplands that are potentially suitable for growing cellulosic feedstock crops (e.g., switchgrass) in the US Great Plains (GP). Satellitederived growing season Normalized Difference Vegetation Index, a switchgrass biomass productivity map obtained from a previous study, US Geological Survey (USGS) irrigation and crop …

Elevation Dynamics In A Restored Versus A Submerging Salt Marsh In Long Island Sound, Shimon C. Anisfeld, Troy D. Hill, Daonald R. Cahoon

United States Geological Survey: Staff Publications

Accelerated sea-level rise (SLR) poses the threat of salt marsh submergence, especially in marshes that are relatively low-lying. At the same time, restoration efforts are producing new low-lying marshes, many of which are thriving and avoiding submergence. To understand the causes of these different fates, we studied two Long Island Sound marshes: one that is experiencing submergence and mudflat expansion, and one that is undergoing successful restoration. We examined sedimentation using a variety of methods, each of which captures different time periods and different aspects of marsh elevation change: surface-elevation tables, marker horizons, sediment cores, and sediment traps. We also …

Processes Contributing To Resilience Of Coastal Wetlands To Sea-Level Rise, Camille L. Stagg, Ken W. Krauss, Donald R. Cahoon, Nicole Cormier, William H. Conner, Christopher M. Swarzenski

United States Geological Survey: Staff Publications

The objectives of this study were to identify processes that contribute to resilience of coastal wetlands subject to rising sea levels and to determine whether the relative contribution of these processes varies across different wetland community types. We assessed the resilience of wetlands to sea-level rise along a transitional gradient from tidal freshwater forested wetland (TFFW) to marsh by measuring processes controlling wetland elevation. We found that, over 5 years of measurement, TFFWs were resilient, although some marginally, and oligohaline marshes exhibited robust resilience to sea-level rise. We identified fundamental differences in how resilience is maintained across wetland community types, …