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Chaco Canyon, New Mexico: A Caretaker City And A Pilgrimage Destination, Larry Benson, Deanna N. Grimstead, John R. Stein, David A. Roth, Terry I. Plowman 2019 University of Colorado at Boulder

Chaco Canyon, New Mexico: A Caretaker City And A Pilgrimage Destination, Larry Benson, Deanna N. Grimstead, John R. Stein, David A. Roth, Terry I. Plowman

United States Geological Survey: Staff Publications

Some Southwestern archaeologists continue to ascribe to the hypothesis that Chaco was agriculturally productive to the point that it could support at least a few thousand full-time residents. This paper suggests an alternative hypothesis; i.e., Chaco was marginally productive and could only support a few hundred permanent residents. Isotopic analysis of mammal teeth found in trenches cut through platform mounds fronting Pueblo Bonito indicate the possibility that much of the meat consumed by Chacoan residents and visitors came from higher elevation sites bordering the San Juan Basin. We suggest that resident population estimates based on great house room numbers and …


Spatial Conservation Planning Under Uncertainty: Adapting To Climate Change Risks Using Modern Portfolio Theory, Mitchell J. Eaton, Simeon Yurek, Zulqarnain Haider, Julien Martin, Fred Johnson, Bradley J. Udell, Hadi Charkhgard, Changhyun Kwon 2019 USGS Patuxent Wildlife Research Center

Spatial Conservation Planning Under Uncertainty: Adapting To Climate Change Risks Using Modern Portfolio Theory, Mitchell J. Eaton, Simeon Yurek, Zulqarnain Haider, Julien Martin, Fred Johnson, Bradley J. Udell, Hadi Charkhgard, Changhyun Kwon

United States Geological Survey: Staff Publications

Climate change and urban growth impact habitats, species, and ecosystem services. To buffer against global change, an established adaptation strategy is designing protected areas to increase representation and complementarity of biodiversity features. Uncertainty regarding the scale and magnitude of landscape change complicates reserve planning and exposes decision makers to the risk of failing to meet conservation goals. Conservation planning tends to treat risk as an absolute measure, ignoring the context of the management problem and risk preferences of stakeholders. Application of risk management theory to conservation emphasizes the diversification of a portfolio of assets, with the goal of reducing the …


Flood-Inundation Maps For The North Platte River At Scottsbluff And Gering, Nebraska, 2018, Kellan R. Strauch 2019 U.S. Geological Survey

Flood-Inundation Maps For The North Platte River At Scottsbluff And Gering, Nebraska, 2018, Kellan R. Strauch

United States Geological Survey: Publications

Digital flood-inundation maps for an 8.8-mile reach of the North Platte River, from 1.5 miles upstream from the Highway 92 bridge to 3 miles downstream from the Highway 71 bridge in Scottsbluff County, were created by the U.S. Geological Survey (USGS) in cooperation with the Cities of Scottsbluff and Gering, Nebraska. The flood-inundation maps, which can be accessed through the Flood Inundation Mapping (FIM) Program website at https://www.usgs.gov/mission-areas/water-resources/science/flood-inundation-mapping-fim-program?qt-science_center_objects=0#qt-science_center_objects, depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the USGS streamgage on the North Platte River at Scottsbluff, Nebr. (station number 06680500). Near-real-time …


Tectonics Of The Incipient Continental Rifting, Youqiang Yu, Cory Reed, Kelly H. Liu, Stephen S. Gao 2019 Missouri University of Science and Technology

Tectonics Of The Incipient Continental Rifting, Youqiang Yu, Cory Reed, Kelly H. Liu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

No abstract provided.


Reprocessing And Comparison Of The 2 Hz And 10 Hz Vertical Component Seismic Data Of The Blackfoot 3c-2d Survey, Mete Sarikaya 2019 Missouri University of Science and Technology

Reprocessing And Comparison Of The 2 Hz And 10 Hz Vertical Component Seismic Data Of The Blackfoot 3c-2d Survey, Mete Sarikaya

Masters Theses

"The Blackfoot seismic 3C-2D data were obtained from the Consortium for Research in Elastic Wave Exploration Seismology (CREWES) Project in 1995. The seismic data acquisition was performed in the Blackfoot Field, which is around 15 km southeast of Strathmore, Alberta. The 4 Hz and 10 Hz vertical component data are reprocessed to increase the quality and resolution of the seismic images. The Glauconitic sand reservoir at approximately 1.1 s, and a strong reflection about at 1.5 s are the focuses of the study.

The processing procedure includes different parameters and methods to obtain the best seismic sections of 2 Hz …


Experimental Preservation Of Muscle Tissue In Quartz Sand And Kaolinite: Supplemental Information, Sharon A. Newman, Mirna Daye, Sirine C. Fakra, Matthew A. Marcus, Mihkel Pajusalu, Sara B. Pruss, Emily F. Smith, Tanja Bosak 2019 Massachusetts Institute of Technology

Experimental Preservation Of Muscle Tissue In Quartz Sand And Kaolinite: Supplemental Information, Sharon A. Newman, Mirna Daye, Sirine C. Fakra, Matthew A. Marcus, Mihkel Pajusalu, Sara B. Pruss, Emily F. Smith, Tanja Bosak

Geosciences: Faculty Publications

Siliciclastic sediments of the Ediacaran Period contain exceptionally preserved fossils of macroscopic organisms, including three-dimensional casts and molds commonly found in sandstones and siltstones and some two-dimensional compressions reported in shales. The sporadic and variable associations of these exceptionally preserved macroscopic fossils with pyrite, clay minerals, and microbial fossils and textures complicate our understanding of fossilization processes. This hinders inferences about the evolutionary histories, tissue types, original morphologies, and lifestyles of the enigmatic Ediacara biota. Here, we investigate the delayed decay of scallop muscles buried in quartz sand or kaolinite for 45 days. This process occurs in the presence of …


New Source-To-Sink Approach In An Arctic Catchment Based On Hyperspectral Core-Logging (Lake Linné, Svalbard), Antonin Van Exem, Maxime Debret, Yoann Copard, Charles Verpoorter, Gregory De Wet, Nicolas Lecoq, Philippe Sorrel, Alan Werner, Steven Roof, Benoit Laignel, Michael Retelle 2019 CNRS Centre National de la Recherche Scientifique

New Source-To-Sink Approach In An Arctic Catchment Based On Hyperspectral Core-Logging (Lake Linné, Svalbard), Antonin Van Exem, Maxime Debret, Yoann Copard, Charles Verpoorter, Gregory De Wet, Nicolas Lecoq, Philippe Sorrel, Alan Werner, Steven Roof, Benoit Laignel, Michael Retelle

Geosciences: Faculty Publications

No abstract provided.


Spatial Conservation Planning Under Uncertainty: Adapting To Climate Change Risks Using Modern Portfolio Theory, Mitchell J. Eaton, Simeon Yurek, Zulqarnain Haider, Julien Martin, Fred A. Johnson, Bradley J. Udell, Hadi Charkhgard, Changhyun Kwon 2019 U.S. Geological Survey, North Carolina State University

Spatial Conservation Planning Under Uncertainty: Adapting To Climate Change Risks Using Modern Portfolio Theory, Mitchell J. Eaton, Simeon Yurek, Zulqarnain Haider, Julien Martin, Fred A. Johnson, Bradley J. Udell, Hadi Charkhgard, Changhyun Kwon

United States Geological Survey: Staff Publications

Climate change and urban growth impact habitats, species, and ecosystem services. To buffer against global change, an established adaptation strategy is designing protected areas to increase representation and complementarity of biodiversity features. Uncertainty regarding the scale and magnitude of landscape change complicates reserve planning and exposes decision makers to the risk of failing to meet conservation goals. Conservation planning tends to treat risk as an absolute measure, ignoring the context of the management problem and risk preferences of stakeholders. Application of risk management theory to conservation emphasizes the diversification of a portfolio of assets, with the goal of reducing the …


Maps Showing The Physical Hydrogeology And Changes In Saturated Thickness (Predevelopment To Spring 2016 And Spring 2011 To Spring 2016) In The Middle Republican Natural Resources District, Southwestern Nebraska., Jesse T. Korus Dr., Leslie M. Howard 2019 University of Nebraska-Lincoln

Maps Showing The Physical Hydrogeology And Changes In Saturated Thickness (Predevelopment To Spring 2016 And Spring 2011 To Spring 2016) In The Middle Republican Natural Resources District, Southwestern Nebraska., Jesse T. Korus Dr., Leslie M. Howard

Conservation and Survey Division: Faculty and Staff Publications

This report accompanies fourteen new maps summarizing the hydrogeology and changes in saturated thickness in the Middle Republican Natural Resources District (MRNRD). The purpose of these maps is to assist the MRNRD in their groundwater management programs and in planning and installing an observation well network. Maps include:

• base of the principal aquifer;

• water table surfaces for predevelopment, Spring 2011, and Spring 2016;

• saturated thicknesses for predevelopment, Spring 2011, and Spring 2016;

• changes in saturated thickness (both in absolute magnitude and in percent) from predevelopment to Spring 2016 and from Spring 2011 to Spring 2016;

• …


A Critical Review Of Using High Viscosity Friction Reducers As Fracturing Fluids For Hydraulic Fracturing Applications, Mohammed Ba Geri, Abdulmohsin Imqam, Ralph E. Flori 2019 Missouri University of Science and Technology

A Critical Review Of Using High Viscosity Friction Reducers As Fracturing Fluids For Hydraulic Fracturing Applications, Mohammed Ba Geri, Abdulmohsin Imqam, Ralph E. Flori

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The primary purpose of using traditional friction reducers in stimulation treatments is to overcome the tubular drag while pumping at high flow rates. Hydraulic fracturing is the main technology used to produce hydrocarbon from extremely low permeability rock. Even though slickwater (water fracturing with few chemical additives) used to be one of the most common fracturing fluids, several concerns are still associated with its use, including usage of freshwater, high-cost operation, and environmental issues. Therefore, current practice in hydraulic fracturing is to use alternative fluid systems that are cost effective and have less environmental impact, such as fluids which utilize …


A Record Of The Precambrian-Cambrian Transition In Sw Montana: A Late Neoproterozoic To Early Cambrian Stratigraphic Window, Fortunian Biostratigraphic Assemblage And Treptichnus Pedum, R. Reid Trippe 2019 University of Montana, Missoula

A Record Of The Precambrian-Cambrian Transition In Sw Montana: A Late Neoproterozoic To Early Cambrian Stratigraphic Window, Fortunian Biostratigraphic Assemblage And Treptichnus Pedum, R. Reid Trippe

Graduate Student Theses, Dissertations, & Professional Papers

This study documents a Late Neoproterozoic through Early Cambrian stratigraphic record in the Humbolt anticline of southwestern Montana. The Precambrian-Cambrian transition includes a Fortunian-aged biostratigraphic trace-fossil assemblage with the ichnofossil Treptichnus pedum. The Humbolt anticline represents an inverted paleo-graben that exposes a stratigraphic window interpreted to be a record of rifting along the Cordilleran miogeoclinal margin, linked with the breakup of the Rodinia supercontinent. The graben subsided and captured sediment during late-stage rifting and final-stage dissociation along the rift margin. Its structural axis paralleled the rift margin. Sevier/Laramide orogenic thrusting inverted the graben into the Humbolt anticline. The Late …


Biodiversity And Distribution Of Benthic Foraminifera In Harrington Sound, Bermuda: The Effects Of Physical And Geochemical Factors On Dominant Taxa, Nam Le 2019 Colby College

Biodiversity And Distribution Of Benthic Foraminifera In Harrington Sound, Bermuda: The Effects Of Physical And Geochemical Factors On Dominant Taxa, Nam Le

Honors Theses

Harrington Sound, Bermuda, is a nearly enclosed lagoon acting as a subtropical/tropical, carbonate-rich basin in which carbonate sediments, reef patches, and carbonate-producing organisms accumulate. Here, one of the most important calcareous groups is the Foraminifera. Analyses of common benthic orders, including miliolids (Quinqueloculina and Triloculina spp.) and rotaliids (Homotrema rubrum, Elphidium spp., and Ammonia beccarii), are essential in understanding past and present environmental conditions affecting the island's coastal environment. These taxa have been studied previously; however, factors explaining their individual patterns of abundance in the Sound are not well detailed. The goal of this study is …


Neotectonics And Pale Earthquakes Along Mae Hong Son Fault, Northern Thailand, Chanista Chansom 2019 Faculty of Science

Neotectonics And Pale Earthquakes Along Mae Hong Son Fault, Northern Thailand, Chanista Chansom

Chulalongkorn University Theses and Dissertations (Chula ETD)

Mae Hong Son Fault (MHSF) is a north-south-trending active fault in Northern Thailand. Last earthquake occurred on February, 1975 with a magnitude of 5.6 at Ban Tha Song Young in Tak Province. This study aims to describe morphological characteristics of MHSF using high (12.5m) resolution Digital Elevation Model (DEM) and to evaluate paleoearthquake magnitudes, recurrence intervals, and slip rates of MHSF by excavating paleoearthquake trenches. According to morphotectonic analysis, offset streams, linear valleys, triangular facets and scarplets were formed as a result of dextral movement within the active fault zone. There are two separate basins associated with the MHSF, which …


Petrology, Provenance, And Depositional Setting Of The Lower Tallahatta Formation (Meridian Sand) In Grenada County, Mississippi, Husamaldeen Zubi 2019 University of Mississippi

Petrology, Provenance, And Depositional Setting Of The Lower Tallahatta Formation (Meridian Sand) In Grenada County, Mississippi, Husamaldeen Zubi

Electronic Theses and Dissertations

The Meridian Sand represents the lowermost member of the Middle Eocene Tallahatta Formation, which is found in the Gulf Coast region of the United States. Five stratigraphic sections in Grenada County were measured and described. Twenty-one sand and sandstone samples, and 2 mud samples were collected from all sections. Textural analyses were performed on all 23 samples to determine their lithologic properties. Petrographic descriptions and modal analyses were performed on thin sections made from the 21 sand and sandstone samples, and 400 grains were point counted in each sample. Geochemical analyses were carried out on all sand, sandstone, and mud …


Generalized Radial Transport Model For Interpreting Convergent Flow Tracer Tests In Fractured Rock, Md Lal Mamud 2019 University of Mississippi

Generalized Radial Transport Model For Interpreting Convergent Flow Tracer Tests In Fractured Rock, Md Lal Mamud

Electronic Theses and Dissertations

The double-porosity Generalized Radial Transport (GRT) model is an extension of the generalized radial flow approach developed for hydraulic test interpretation. In both approaches, a flow dimension characterizes the change in flow area versus radial distance from the borehole. The GRT model collapses to a 1D, radial, and spherical advection dispersion equation (ADE) for integer flow dimensions of 1, 2, and 3, respectively. And, the model also transforms to sub-linear, sub-radial, sub-spherical and eventually transform to super-spherical transport model for non-integer flow dimension, n of 0 < n < 1, 1 < n < 2, 2 < n < 3 and n >3 respectively. Non-integer flow dimensions, especially sub-radial, are commonly reported from pumping tests in …


Detrital Zircon Provenance And Correlation Of Two Newly Discovered Ripley Formation Bentonites: Pontotoc County, Mississippi, Elizabeth Jayne Vitale 2019 University of Mississippi

Detrital Zircon Provenance And Correlation Of Two Newly Discovered Ripley Formation Bentonites: Pontotoc County, Mississippi, Elizabeth Jayne Vitale

Electronic Theses and Dissertations

Two newly discovered bentonite deposits in northern and southern Pontotoc County, Mississippi occur in the Upper Cretaceous outcrop in a banded pattern on the northeastern margin of the Mississippi Embayment (MSE). The entire Ripley Formation (Fm) consists of ~73 m of fossiliferous clay, sand, and calcareous sand beds. The bentonites are located stratigraphically within the Chiwapa Sandstone Member (CSM) at the top of the Ripley Fm and stratigraphically lie above previously mined bentonites in central Pontotoc County. Since the northern and southern bentonites differ stratigraphically from the previously mined bentonites, it is possible that there are other unknown bentonite deposits …


Carbon In The Deep Biosphere: Forms, Fates, And Biogeochemical Cycling, Susan Q. Lang, Magdalena R. Osburn, Andrew D. Steen 2019 University of South Carolina - Columbia

Carbon In The Deep Biosphere: Forms, Fates, And Biogeochemical Cycling, Susan Q. Lang, Magdalena R. Osburn, Andrew D. Steen

Faculty Publications

Building on the synthesis of carbon reservoirs in Earth's subsurface, this chapter focuses on the forms, cycling, and fate of the carbon supporting microbial life in the terrestrial and marine subsurface. As the subsurface is estimated to host a vast reservoir of life on Earth, identifying the carbon compounds that life uses for energy and growth is key to understanding ecosystem functioning in the past and at present, and also for extrapolating these findings to the search for life in the universe. This chapter highlights advances in quantifying small carbon compounds, measuring rates of carbon turnover, and the fate of …


Ua66/8/3 Ogden College Of Science & Engineering Geography & Geology Publications, WKU Archives 2019 Western Kentucky University

Ua66/8/3 Ogden College Of Science & Engineering Geography & Geology Publications, Wku Archives

WKU Archives Collection Inventories

Publications created by and about the Geography & Geology department.


Testing For Sedimentary Recycling Using Detrital Monazite Geochronology, Zircon “Double Dating”, And Textures In Pennsylvanian Arenites Of The Central Appalachian Basin, Eastern Kentucky: Implications For Single Mineral Sedimentary Provenance Analysis, Steve C. Zotto 2019 University of Kentucky

Testing For Sedimentary Recycling Using Detrital Monazite Geochronology, Zircon “Double Dating”, And Textures In Pennsylvanian Arenites Of The Central Appalachian Basin, Eastern Kentucky: Implications For Single Mineral Sedimentary Provenance Analysis, Steve C. Zotto

Theses and Dissertations--Earth and Environmental Sciences

Detrital monazite Th-Pb and detrital zircon U-Pb and U-Th/He double-dating coupled with sandstone petrography and exhumation rates can be used to test for sediment recycling in Pennsylvanian sandstones within the Alleghenian clastic wedge. The Alleghenian clastic wedge is a logical system in which to test for sediment recycling as four major collisional events (Grenville, Taconic, Acadian and Alleghenian orogenies) likely reworked the continental margin and recycled siliciclastic sediment. The combination of these geochronologic and thermochronologic methods provide a more accurate assessment of the proportion of recycled sediment in the Grundy Formation (sublitharenite) and the Corbin Sandstone (quartz arenite), which past …


Mineral Exploration And Sustainable Development: A Case Study In The Republic Of South Sudan, Cosmas Pitia Kujjo 2019 University of Kentucky

Mineral Exploration And Sustainable Development: A Case Study In The Republic Of South Sudan, Cosmas Pitia Kujjo

Theses and Dissertations--Earth and Environmental Sciences

South Sudan, a new country formed in 2011, has been planning to develop its mineral sector by allocating exploration licenses to investors. This decision requires preliminary knowledge of geology and mineral occurrences, both of which are unavailable because the country has been engaged in a civil war for more than 50 years. Exploration of mineral resources in South Sudan has lagged behind its petroleum industry, except for artisanal gold mining, which is practiced intermittently by local communities. Freely available satellite gravity and remote-sensing data were used to map the basement architecture as well as zones of hydrothermal alteration in the …


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