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The Effects Of Habitat Isolation On Fine-Scale Genetic And Geographic Structure Of Populations Of Two Threatened Endemic Insects In Southern Nevada, Pseudocotalpa Giulianii And Icaricia Shasta Charlestonensis, Kristen Tovar May 2023

The Effects Of Habitat Isolation On Fine-Scale Genetic And Geographic Structure Of Populations Of Two Threatened Endemic Insects In Southern Nevada, Pseudocotalpa Giulianii And Icaricia Shasta Charlestonensis, Kristen Tovar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Assessing the role geographic isolation and ecological specialization have on phylogeographic patterns contributes to our understanding of the evolutionary history of a species and the processes that erode genetic diversity. I used mitochondrial and nuclear genomic sequences to assess whether habitat isolation has shaped the fine-scale patterns of present-day genetic structure and diversity in two threatened insect species endemic to southern Nevada. Pseudocotalpa giulianii (Coleoptera; Scarabaeidae) is a dune obligate scarab beetle endemic to only two small, isolated sand dunes in Nye County, Nevada, with a usable habitat of less than 4.2 km sq that is impacted by on-going degradation. …


Use Of Healthcare Utilization Records For Analyzing Trends In Clinical Toxoplasmosis: A Comparison Of Nevada And The United States, Elijah Kreutzer Dec 2022

Use Of Healthcare Utilization Records For Analyzing Trends In Clinical Toxoplasmosis: A Comparison Of Nevada And The United States, Elijah Kreutzer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Toxoplasmosis, a zoonotic disease caused by the parasitic protist Toxoplasma gondii, is a ubiquitous, global public health concern with a wide variety of clinical manifestations. Surveillance for the disease is lacking even in developed countries, and what surveillance is present most often focuses on pregnant women. This research investigated trends in clinical toxoplasmosis in Nevada and nationally to address the lack of knowledge concerning how Nevada discharges compare to national discharges in cases of toxoplasmosis. Specifically, this research sought to determine what characterizes toxoplasmosis in Nevada across inpatient, outpatient, and emergency department settings, as well as how these cases differ …


Gardasil Vaccine Trends Within Nevada, California, And The U.S.: A Comparative Study, Karen S. Gutierrez Dec 2020

Gardasil Vaccine Trends Within Nevada, California, And The U.S.: A Comparative Study, Karen S. Gutierrez

UNLV Theses, Dissertations, Professional Papers, and Capstones

Despite decreasing incidence in cervical cancer in the U.S., there continues to be an increase in public health concern for cervical cancer worldwide. Recent studies report that individuals are disproportionately affected based on region, sex, and race. Additionally, the human papillomavirus (HPV) attributable cancers may be reduced between 70% and 90% through the universal use of HPV-vaccines. In order to expand current knowledge and implement intervention programs in Nevada, it is critical to examine the associations among the Gardasil vaccine, cervical cancer screening, and adverse events following immunization as well as to understand the different socio-demographic subgroups affected. To our …


An Analysis Of Postmastectomy Breast Reconstruction Due To Breast Cancer In Nevada And The United States From 2008-2013, Jenna Webb May 2019

An Analysis Of Postmastectomy Breast Reconstruction Due To Breast Cancer In Nevada And The United States From 2008-2013, Jenna Webb

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: In the United States, female breast cancer was the leading cause of new cancer cases from 2011-2015. Since the Women’s Health and Cancer Act of 1998 (WHCRA), the federal government mandates employee and private health insurance providers to cover breast reconstruction if they cover mastectomies. Postmastectomy breast reconstruction (PBR) rates increased after the WHCRA, but these rates have remained relatively low throughout recent years. Objective: The objective of this study was to determine factors associated with women having PBR due to breast cancer in Nevada and the United States from 2008 to 2013. Methods: Using two HCUP database, NIS …


Seismic Analysis Of The 30 July 1972 Sitka Earthquake Aftershocks, Stress Drop Of Aftershocks In Cook Strait, New Zealand Following The 2013 Cook Strait And Lake Grassmere And 2016 Kaikoura Earthquakes, And 2d Seismic Tomography In The Brady Hot Springs Geothermal Site, Nevada, Juan Alejandro Ochoa Chavez Jan 2019

Seismic Analysis Of The 30 July 1972 Sitka Earthquake Aftershocks, Stress Drop Of Aftershocks In Cook Strait, New Zealand Following The 2013 Cook Strait And Lake Grassmere And 2016 Kaikoura Earthquakes, And 2d Seismic Tomography In The Brady Hot Springs Geothermal Site, Nevada, Juan Alejandro Ochoa Chavez

Open Access Theses & Dissertations

The 1972 Mw 7.6 Sitka earthquake is the largest earthquake to have occurred along the Alaska portion of the Queen Charlotte fault (QCF) in historic time. The QCF system forms the plate boundary between the Pacific and North American plates within southeastern Alaska and has accumulated enough slip since 1972 to produce a comparable sized event in the near future. Thus, it is important to better understand the controls on the rupture process of the 1972 mainshock and its aftershocks. Following the mainshock the U.S. Geological Survey installed a network of 11 portable seismographs that recorded over 200 aftershocks of …


Crustal Seismic Anisotropy Of The Ruby Mountains Core Complex And Surrounding Northern Basin And Range, Justin T. Wilgus Oct 2018

Crustal Seismic Anisotropy Of The Ruby Mountains Core Complex And Surrounding Northern Basin And Range, Justin T. Wilgus

Earth and Planetary Sciences ETDs

Metamorphic core complexes (MCC) are distinctive uplifts that expose deeply exhumed and deformed crustal rocks due to localized extensional deformation. Consequently, their detailed structure provide a window into deep crustal mechanics. The North American Cordillera contains numerous MCC, one of which is the Ruby Mountains core complex (RMCC) located in the highly extended northern Basin and Range. To constrain the extent to which anisotropy below the RMCC deviates from the regional Basin and Range average and test the depth dependence of crustal anisotropy we conduct a radial anisotropy investigation below the RMCC and surrounding northern Basin and Range. Data from …


Structural Evolution And Regional Implications Of The Arrowhead Mine Fault Within The Pahranagat Shear Zone, Nevada, Usa, Michael Dennis Evans May 2018

Structural Evolution And Regional Implications Of The Arrowhead Mine Fault Within The Pahranagat Shear Zone, Nevada, Usa, Michael Dennis Evans

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Basin and Range province is characterized by normal faults associated with

extension, but the occurrence of strike-slip faults and the seismic hazard accompanying

them is less understood. One major strike-slip zone, the Pahranagat shear zone (PSZ),

lies in Lincoln County, Nevada and within the boundary zone between northern Basin

and Range (NBR) and central Basin and Range (CBR) sub-provinces. The PSZ is a 20-

25 km long zone of Cenozoic left-lateral faults. The Arrowhead Mine Fault (AMF) is one

of the three major faults in the PSZ. The western AMF and the faults that surround and

abut it are …


Late-Quaternary Seismic Stratigraphic Framework And Paleolimnology Of Walker Lake, Nevada, Mattie Friday May 2018

Late-Quaternary Seismic Stratigraphic Framework And Paleolimnology Of Walker Lake, Nevada, Mattie Friday

Theses - ALL

The western USA has experienced heightened sensitivity to drought in recent years, and these conditions are compounded by a rapidly expanding population. Lake deposits are sensitive archives useful for reconstructing past hydroclimate, and such paleorecords can provide constraints for future planning. Walker Lake, Nevada is a terminal basin in the westernmost Basin and Range province. It contains a long sediment record extending at least to the late Pleistocene. Ten sediment cores, and ~300 km of CHIRP seismic reflection data were acquired from the lake in 2013 to develop a detailed environmental history from the lake’s stratigraphic record. Seven sequences were …


The Impact Of Economic Recession On The Health Of Adult Nevadans, Ariana Goertz Dec 2017

The Impact Of Economic Recession On The Health Of Adult Nevadans, Ariana Goertz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Recessions are generally considered to cause negative consequences, but recent studies have provided evidence that some health outcomes improve as the economy deteriorates. The relationship between economic downfalls and health is not straightforward; it is important to look at how health has been impacted in one of the areas hit hardest by the recession. Las Vegas, Nevada was previously considered recession-proof, seemingly unaffected by previous economic downturns exhibited by the rest of the country. However, during the Great Recession of 2007-2009, Las Vegas led the country in highest rates of unemployment and foreclosures. This was quite a collapse for a …


Investigations On The Mesozoic Geologic And Tectonic History Of The Jackson Mountains, Northwest Nevada, Thomas Anthony Colby May 2017

Investigations On The Mesozoic Geologic And Tectonic History Of The Jackson Mountains, Northwest Nevada, Thomas Anthony Colby

Boise State University Theses and Dissertations

New geologic mapping, high-precision U-Pb zircon geochronology, and isotope geochemistry provide insight into the early Mesozoic paleogeography and magmatic, stratigraphic, and structural evolution of the Jackson Mountains in the Black Rock Desert region of northwest Nevada. The magmatic history of the Jackson Mountains records Late Triassic to Early Jurassic (~215-195 Ma) marine deposition of the Boulder Creek Beds adjacent to the arc followed by the Early Jurassic (~193-189 Ma) eruption and emplacement of the Happy Creek Igneous Complex and associated plutons of the Early Mesozoic Intrusive Suite. Pb, Sr, and Nd isotopic data from Early Jurassic intrusive rocks of the …


Characterization Of Dust On Solar Devices In Southern Nevada, Jason Sylva May 2017

Characterization Of Dust On Solar Devices In Southern Nevada, Jason Sylva

UNLV Theses, Dissertations, Professional Papers, and Capstones

Dust can impact the efficiency of solar energy collection devices, and in some arid environments, dust can reduce solar energy efficiency up to 30%. Reducing the impact of dust is therefore critical in the expansion of solar technology throughout regions where solar energy is utilized. Characterization of suspended and settled particulate matter can assist in developing strategies for dust mitigation. With the characterization of suspended and settled particulate in remote, rural, and urban environments, more informed decisions can be made regarding the selection of coating material on solar panels as well as developing cleaning and maintenance procedures. Particulate matter that …


Architectural Form, Orientation, And Energy For Residential Design In The Southern Nevada Region., Ludwing Vaca Dec 2015

Architectural Form, Orientation, And Energy For Residential Design In The Southern Nevada Region., Ludwing Vaca

UNLV Theses, Dissertations, Professional Papers, and Capstones

With the population increase, the high demand of energy from the residential sector, as well as the harsh weather conditions of the Las Vegas region, there needs to be careful consideration in the design of new homes. Energy efficiency in a single family residential building can be augmented early in the design process by careful consideration of the building form and orientation. A systematic investigation and analysis was taken to study the effects of five building forms and different orientations along the cardinal points using the software BEopt version 2.4.0.1. To connect the study to real world circumstances, a residential …


Keeping In Touch: Exchange As An Adaptive Strategy In Southern Nevada, Timothy Joshua Ferguson Dec 2014

Keeping In Touch: Exchange As An Adaptive Strategy In Southern Nevada, Timothy Joshua Ferguson

UNLV Theses, Dissertations, Professional Papers, and Capstones

Archaeologists have always wondered about the extent of vessel movement in the American Southwest. Identifying vessel movement allows for the study of social interactions across a region and the role of ceramics in the adaptive processes of agriculturalists living in marginal, highly variable environments. In many instances, exchange may act as a way to reduce the risk of resource shortfalls by creating social ties in other areas. This research investigated the changing risk reduction strategies of households in the lowland Virgin region of southern Nevada by using geochemical methods to trace the exchange of locally produced pottery. It was hypothesized …


Controls On Fault Geometry During Early Stages Of Extension In The Larkspur Hills, Northwest Basin And Range, Diana Jean Strickley Jan 2014

Controls On Fault Geometry During Early Stages Of Extension In The Larkspur Hills, Northwest Basin And Range, Diana Jean Strickley

All Master's Theses

Detailed analyses of normal faults in the Larkspur Hills, CA-NV, northwest Basin and Range, offer insight into factors controlling normal fault initiation, growth, and distribution. N-trending faults in the southern portion of the study area share trends of major range-bounding structures and Pliocene linear volcanic vents; in contrast, NNW- and NNE- trending faults dominate further north and into south-central Oregon. Stress analyses and comparison with experimental and field data suggest that preexisting structures control faults in the northern Larkspur Hills, while faults form perpendicular to σ3 in the southern hills. The change in fault orientations is abrupt, occurring across a …


Ichnology And Paleoecology Of The Jurassic Aztec Sandstone, Heather Marie Stoller Dec 2013

Ichnology And Paleoecology Of The Jurassic Aztec Sandstone, Heather Marie Stoller

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study I describe and interpret tracks and trackways of the Jurassic Aztec Sandstone of southern Nevada and southern California. This study involved mapping of all known tracks and trackways, including foot length, stride length, and trackway width. Photogrammetric data, collected by Bureau of Land Management scientists, were utilized for several trackways in Red Rock Canyon National Conservation Area.

More than three hundred tracks belonging to five ichnotaxa were documented within the Aztec Sandstone, including about 165 tridactylGrallator, 250 tetradactyl (four-toed)Brasilichniumtracks, and 7 arthropod trackways ofOctopodichnusandPaleohelcura. Four of the five ichnotaxa were not previously reported from the Aztec Sandstone. …


Paleoecology Of Late Pleistocene Megaherbivores: Stable Isotope Reconstruction Of Environment, Climate, And Response, Aubrey Mae Bonde Aug 2013

Paleoecology Of Late Pleistocene Megaherbivores: Stable Isotope Reconstruction Of Environment, Climate, And Response, Aubrey Mae Bonde

UNLV Theses, Dissertations, Professional Papers, and Capstones

Late Pleistocene megaherbivore communities of the Pacific and Mountain West states of California and Nevada are under-analyzed in regard to ecological function (diet, mobility, niche partitioning, and range of ecological tolerance). Stable isotope analysis is a powerful tool that is known to recover primary paleodiet and paleoenvironmental information from biogenic materials, such as enamel and dentin. This dissertation explores the use of carbon and oxygen stable isotopes in Late Pleistocene (40-10 Ka) megaherbivore teeth to gain a better understanding of inter- and intra-specific behavior and reconstruct Late Pleistocene ecosystems of California and Nevada. Radiocarbon dates exist for most of the …


Investigating The Feasibility Of Growing Algae For Fuel In Southern Nevada, Faegheh Moazeni May 2013

Investigating The Feasibility Of Growing Algae For Fuel In Southern Nevada, Faegheh Moazeni

UNLV Theses, Dissertations, Professional Papers, and Capstones

Microalgae capable of growing in waste are adequate to be mass-cultivated for biodiesel, avoiding fertilizers and clean water, two obstacles to sustainability of the feedstock production. This study replaces fertilizers and clean water with waste products. The investigated wastes include (1) the liquid fraction of sewage after solids and particles are removed, known as centrate, and (2) algal biomass residue, i.e. the algae remaining at the end of the lipids extraction process at biofuel plants. These wastes contain sufficient amount of nitrogen and phosphorus required for algal growth. This study proposes a system in which centrate would be used as …


Volcanic Evolution Of The Southern Quinn Canyon Range: Implications For Regional Correlation Of Volcanic Units, Christina Emery Dec 2012

Volcanic Evolution Of The Southern Quinn Canyon Range: Implications For Regional Correlation Of Volcanic Units, Christina Emery

UNLV Theses, Dissertations, Professional Papers, and Capstones

The southern Quinn Canyon Range lies in an area of the Great Basin subjected to large-volume Oligocene-Miocene silicic volcanism and smaller volume basaltic volcanism during the Pliocene. Three major ash-flow tuff units were correlated in the southern Quinn Canyon Range (the Pahranagat Tuff, Clifford Spring Tuff, and the Cow Canyon Tuff) with regional units by utilizing U/Pb and 40 Ar/ 39Ar geochronology, geochemical correlation, and field mapping. Isotopic analysis suggests that basalt in the southern Quinn Canyon Range is part of the Death Valley-Pancake Range Basalt Zone and is similar to Reveille Range Episode 1 and 2 basalts. Further comparison …


Detrital Carbonates In A Sequence Stratigraphic Framework: An Example From The Furongian Slope Environment In The Hot Creek Range Of Central Nevada, Leon Taufani Dec 2012

Detrital Carbonates In A Sequence Stratigraphic Framework: An Example From The Furongian Slope Environment In The Hot Creek Range Of Central Nevada, Leon Taufani

UNLV Theses, Dissertations, Professional Papers, and Capstones

An integrated sedimentological study of detrital carbonates of the late Cambrian (Furongian) Hales Limestone in central Nevada was conducted in order to model facies distribution and controlling mechanisms of carbonate gravity-flow deposits. Seven closely-spaced sections and numerous traceable short sections were measured to investigate temporal and spatial changes of detrital carbonates within a high-resolution stratigraphic framework supported by biostratigraphic and carbon isotope chemostratigraphic constraints and by key physical surfaces. Polished slabs and thin section petrographic analysis were used to identify micro- and macro-scale textures and diagenesis.

Ten lithofacies are identified from the Hales Limestone. Lateral tracing of these facies reveals …


Restoration Of Biological Soil Crust On Disturbed Gypsiferous Soils In Lake Mead National Recreation Area, Eastern Mojave Desert, Lindsay P. Chiquoine Dec 2012

Restoration Of Biological Soil Crust On Disturbed Gypsiferous Soils In Lake Mead National Recreation Area, Eastern Mojave Desert, Lindsay P. Chiquoine

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biological soil crusts (BSCs) are sensitive to anthropogenic disturbances. Natural recovery takes many years. Active restoration decreases recovery time. Native BSC inocula, which included lichens and mosses, salvaged from gypsiferous soil habitats in Lake Mead National Recreation Area (LMNRA) in the eastern Mojave Desert were stored dry for two years and applied to disturbed soil after a road reconstruction in LMNRA and also used in laboratory experiments to test inoculation technique effectiveness. After 18 months, field results revealed positive relationships between inoculation and the presence of macroscopic BSC cover, cyanobacteria abundance, soil stability, and ammonium concentrations. Chlorophyll fluorescence monitoring of …


Sustainability Program For Rio Secco Golf Club And Cascata, Jay Chiders Oct 2012

Sustainability Program For Rio Secco Golf Club And Cascata, Jay Chiders

UNLV Theses, Dissertations, Professional Papers, and Capstones

Caesars Entertainment is focused on building loyalty and value with its guests through a unique combination of great service, excellent products, operational excellence, and technology leadership. Caesars is committed to environmental sustainability and energy conservation and recognizes the importance of being a responsible steward to the environment. Sustainability at Caesars Entertainment integrates strategic direction with the energy, innovation, and passion of its 70,000 employees. These employees are what drive Caesars Entertainment’s comprehensive sustainability strategy, CodeGreen (CodeGreen factsheet, 2012).

Caesars Entertainment Corporation owns two golf courses in Nevada. Rio Secco Golf Club opened in 1997 in Henderson and Cascata opened in …


Paleoseismic Study Of The Stewart Valley And Northern Pahrump Segments Of The Stateline Fault System, Nevada, Jonathan Carter Aug 2012

Paleoseismic Study Of The Stewart Valley And Northern Pahrump Segments Of The Stateline Fault System, Nevada, Jonathan Carter

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Stateline fault system (SFS) is a ~200 km long zone of dextral faults running NW along the NV/CA border from Primm, Nevada to Amargosa Valley in the western Central Basin and Range province (CBR). Because of size and proximity, the SFS poses a hazard to the 2.5 million people, most of who live within 10 km, in Pahrump, Nevada and within 40 km, in Las Vegas, Nevada. The goals of this thesis are to (1) understand if the SFS is accommodating faulting slip change in the CBR; (2) test the along strike continuity of the SFS in Pahrump and …


Muddy Creek Formation: A Record Of Late Neogene Tectonics And Sedimentation In Southern Nevada, Thomas William Muntean May 2012

Muddy Creek Formation: A Record Of Late Neogene Tectonics And Sedimentation In Southern Nevada, Thomas William Muntean

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Late Neogene Muddy Creek Formation (MCF), exposed in the vicinity of Lake Mead in southern Nevada, represents the youngest widespread Cenozoic sedimentary sequence in the region and is the focus of this study. Historically, the MCF has been largely ignored, with limited previous studies providing only regional-scale constraint on the age, stratigraphy, and mode of deposition for the formation; resulting in a data gap for our understanding of the Late Cenozoic tectonic and sedimentological evolution of southern Nevada.


Burial And Exhumation History Of Mississippian Strata In East-Central Nevada, Yuki Yunika Agulia May 2012

Burial And Exhumation History Of Mississippian Strata In East-Central Nevada, Yuki Yunika Agulia

UNLV Theses, Dissertations, Professional Papers, and Capstones

Zircon (U-Th)/He analyses and vitrinite reflectance (Ro) analyses were performed on a suite of Mississippian sedimentary rocks collected in east-central Nevada in order to test Permian exhumation described in a previous study.

The zircon analyses produced three clusters of ages: 1) older than, 2) similar to, and 3) younger than depositional age. The majority of zircons shows ages that are older than the sandstone deposition age. Young ages were recorded in three localities that may indicate reset ages/residence within the (U-Th)/He partial retention zone (HePRZ). Moderate-high ratios of Th/U may indicate a magmatic source. Vitrinite reflectance (Ro) analyses show values …


Paired Positive Carbonate Carbon Isotope, Organic Carbon Isotope, And Oxygen Isotope Composition Study Across The Lower Mississippian Positive Carbon Isotope Excursion, Southeastern Nevada, Usa, Robert Alan Henry Dec 2011

Paired Positive Carbonate Carbon Isotope, Organic Carbon Isotope, And Oxygen Isotope Composition Study Across The Lower Mississippian Positive Carbon Isotope Excursion, Southeastern Nevada, Usa, Robert Alan Henry

UNLV Theses, Dissertations, Professional Papers, and Capstones

A prominent positive carbonate carbon isotope (delta13Ccarb) excursion of Early Mississippian age (ca 351 Ma) has been documented by previous studies from numerous sites globally. This delta13Ccarb excursion has been interpreted as resulting from enhanced organic carbon burial that removed 13C-depleted carbon from the ocean and atmosphere. Anticipated outcomes from enhanced organic carbon burial would include a similar positive excursion in organic carbon isotopes (delta13Corg) and a global cooling event resulting from reduced CO2 in the atmosphere and ocean. These predictions, however, were not tested sufficiently in previous studies. This research has tested these predictions through an integrated study of …


Geochronologic And Isotopic Investigation Of The Koipato Formation, Northwestern Great Basin, Nevada: Implications For Late Permian-Early Triassic Tectonics Along The Western U.S. Cordillera, Nicholas Quentin Vetz Aug 2011

Geochronologic And Isotopic Investigation Of The Koipato Formation, Northwestern Great Basin, Nevada: Implications For Late Permian-Early Triassic Tectonics Along The Western U.S. Cordillera, Nicholas Quentin Vetz

Boise State University Theses and Dissertations

The volcanics of the Early Triassic Koipato Formation of central Nevada unconformably overlie the Golconda Allochthon and, classically, this relationship has been used to define the timing of the Sonoma Orogeny as post-Middle Permian to earliest Triassic. However, the Koipato Formation represents a rather isolated magmatic succession, with other western U.S. Early Mesozoic igneous provinces determined to be younger or lacking rocks of Koipato age. This isolation, coupled with the fact that the Koipato Formation does not overlap the Golconda Allochthon, has left open two possible scenarios for its tectonic history: 1) the Koipato Formation represents the earliest, post-Sonoma Orogeny …


Petrogenesis Of The Greenwater Range: Comparison To The Crater Flat Volcanic Field And Implications For Hazard Assessment, Ashley Kaye Tibbetts May 2010

Petrogenesis Of The Greenwater Range: Comparison To The Crater Flat Volcanic Field And Implications For Hazard Assessment, Ashley Kaye Tibbetts

UNLV Theses, Dissertations, Professional Papers, and Capstones

Pliocene basalts of the Greenwater Range, California erupted from 24 volcanic vents now represented by volcanic plugs, craters and scoria mounds. Basaltic magmas originated in the asthenospheric mantle, but show evidence of a lithospheric component. Depths and temperatures of melting calculated using a silica activity geobarometer are 54.3–89.6 km and 1367-1435oC, placing melting in the asthenosphere. The preferred petrogenetic model involves melting of lithospheric mantle thermally and mechanically, but not chemically, converted to asthenospheric mantle. Melting depths correspond to low velocity zones in the mantle as revealed in seismic profiles. Chemical and lithologic similarities between basalt in the Greenwater Range …


Phyllosilicate Mineralogy, 40ar/39ar Geochronology, And Genesis Of Petrocalcic Soils In The Southwest U.S.A., Colin R. Robins May 2010

Phyllosilicate Mineralogy, 40ar/39ar Geochronology, And Genesis Of Petrocalcic Soils In The Southwest U.S.A., Colin R. Robins

UNLV Theses, Dissertations, Professional Papers, and Capstones

Obtaining isotope ages for arid soils and paleosols, including carbonate-cemented (calcic and petrocalcic) horizons, constitutes a significant challenge for soil scientists, geomorphologists, and stratigraphers. Carbonate-cemented soils foster diverse suites of authigenic minerals with exciting potential for geochronology, however, this potential has not been realized. This dissertation describes the timing of pedogenic palygorskite and sepiolite crystallization in extremely old, extant petrocalcic soils of the southwest U.S.A., and assumes that these fibrous, high-magnesium phyllosilicates contain sufficient lattice-bound K to warrant vacuum-encapsulated 40Ar/39Ar geochronology. This three-part study evaluated the (1) selective extraction, (2) 40Ar/39Ar analysis, and (3) pedogenesis of palygorskite and sepiolite.

Effects …


An Exploratory Study On Energy Consumption Of Energy Star And Non-Energy Star Homes, Prajakta Kulkarni May 2010

An Exploratory Study On Energy Consumption Of Energy Star And Non-Energy Star Homes, Prajakta Kulkarni

UNLV Theses, Dissertations, Professional Papers, and Capstones

The reduction of energy consumption is one of the economic necessities in the United States due to depleting energy sources in the world. The construction industry is stepping forward to reduce the energy consumption of buildings by efficient designs or by constructing buildings with energy efficient materials and features. In 1992, the U.S. Environmental Protection Agency (EPA) and Department of Energy (DOE) introduced the Energy Star Program to promote energy efficient products with the same or improved services. According to the EPA, Energy Star homes, which use these products, will consume 20 to 30 percent less energy than non-Energy Star …


Water Use And Natural Limits In The Las Vegas Valley: A History Of The Southern Nevada Water Authority, Christian Harrison Jan 2009

Water Use And Natural Limits In The Las Vegas Valley: A History Of The Southern Nevada Water Authority, Christian Harrison

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis examines the history of the Southern Nevada Water Authority (SNWA) and how it has helped transform various aspects of southern Nevada's economy and environment. Prior to the establishment of the SNWA in 1991 the Las Vegas Metropolitan Area (LVMA) possessed several competing water providers whose opposition to one another adversely affected the management of water in the region. These water providers recognized this problem, came together, and negotiated the creation of a regional water agency, the SNWA. This organization, comprised of representatives from each of the LVMA's water providers has the power to institute policy across municipal boundaries. …