Physical Sciences and Mathematics Commons^™

Analysis And Evaluation Of The Workplace Exposure Assessment Workbook Developed By Keith Tait Including Some Recommended Revisions, Lisa Hebberd

UNLV Theses, Dissertations, Professional Papers, and Capstones

Some risk due to the contamination of workplace environments is an inevitable part of human lives. These risks can often be reduced by improving the control of environmental pollution in the workplace. An extremely important challenge for any industry is to develop a mechanism to identify acceptable levels of safety, or "acceptable risk" in the workplace for specific situations, and to assure adequate quality control over measured or calculated exposure concentrations and their possible contributions to adverse health effects.

Depositional Environments And Paleoecology Of The Lower Ordovician Pogonip Group, Opd Unit, Arrow Canyon Range, Clark County, Nevada, Jeffrey K. Donovan

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Opd Unit of the Pogonip Group is a slope-forming carbonate sequence that crops out in the Arrow Canyon Range 75 miles north of Las Vegas, Nevada. It is composed mainly of grainstones, packstones, and intraformational conglomerates and also contains Calathium-bearing bioherms composed dominantly of wackestones. These rocks were deposited in a shallow-water, high-energy, subtidal, tropical marine environment. Nuia and Nuia-crinoid shoals developed on this shallow ramp and the area was frequently disturbed by storms.

Calathium-dominated carbonate mudmounds emerged on the Nuia and Nuia-crinoid shoals. Although Calathium dominated the mounds on a macroscopic scale, the mounds …

Desorption Hysteresis In Five Ion Exchanged Montmorillonites, Jerry Paul Fairley

UNLV Theses, Dissertations, Professional Papers, and Capstones

It is generally believed that the formation of recalcitrant (slowly desorbing) fractions of volatile organic compounds (VOCs) in soils is due to diffusion of compounds to sorption sites inaccessible to bulk fluid. The exact nature of these sites, however, is not well understood. In clay minerals, researchers favor two probable areas for the storage of persistent contamination; sites between the clay lamella, or sites with clay particle aggregates.

To test the hypothesis that recalcitrant fractions are formed in interlamellar spaces, a Na/Ca Montmorillonite (Smectite) was ion exchanged with five different cations (K⁺, Na⁺, Ca⁺, …

The Sloan Sag: A Mid-Miocene Volcanotectonic Depression, North-Central Mccullough Mountains, Southern Nevada, Hayden L. Bridwell

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the Hidden Valley area of the north-central McCullough Mountains, southern Nevada, mid-Miocene andesite and dacite domes, flows and pyroclastic units (the Sloan volcanics) partially fill a sag in the underlying Hidden Valley volcanics. The 13.5 km diameter sag formed during and/or after the eruption of the Sloan volcanics. Sagging was accommodated by a combination of movement on the McCullough Wash fault system, and subsidence into evacuated chambers.

Major, trace and rare-earth element geochemistry suggests that the rocks of the Sloan volcanics belong to four groups, each of which were produced by partial melting of chemically distinct sources. With the …

Hydrogeology And Hydrogeochemistry Of The Shallow Alluvial Aquifer Zone, Las Vegas Valley, Nevada, Harry Stephen Wild Jr.

UNLV Theses, Dissertations, Professional Papers, and Capstones

In Las Vegas Valley, Nevada, the shallow alluvial aquifer zone is a possible source of contamination to the principal alluvial aquifers that provide 30% of the public drinking water supply for the valley. Development of the principal aquifers has lowered pressure head in the principal aquifers and created the potential for downward seepage from the shallow aquifer zone. This study was undertaken to characterize the hydrogeology and hydrogeochemistry of the shallow alluvial aquifer zone and to compare the hydrogeochemistry of the shallow and principal alluvial aquifer zones.

A 37 well shallow ground water monitoring network was established and water-level, water-quality, …

Stromatolites Of The Lower Cambrian Deep Spring Formation; Mount Dunfee, Esmeralda County, Nevada, Lynn Oliver

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Middle Member of the Lower Cambrian Deep Spring Formation at Mount Dunfee, Nevada contains a diverse assemblage of stromatolites that formed on a tide- and storm-dominated, siliciclastic-influenced, carbonate shelf. The stromatolites formed in a shallow subtidal environment within and near active oolite shoals under strongly focused currents. The stromatolites occur in four different lithofacies: (1) bioherms of digitate stromatolites, (2) bioherms and biostromes of inclined stromatolites, (3) isolated forms of massive and hemispheroidal stromatolites, and (4) a biostrome of cryptomicrobial boundstones. The first three lithofacies are interpreted as microbial reefs. They had topographic relief, formed in active agitated waters, …

Late-Holocene Earthflows Of The Willard Playa/Dune Complex, Estancia Valley, New Mexico: A Geomorphic Response To Climatic Change, Kurt A. Goebel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Late-middle to late Holocene dune sediment that overlies Pleistocene lacustrine sediment marks the onset of xeric conditions in the Estancia Valley, central New Mexico. Incised into the underlying lacustrine sediments, the modern deflation basins are enclosed by parabolic dunes composed of clay and gypsum derived from the underlying sediment.

Located on the in-facing dune slopes of the deflation basins, the most striking geomorphic feature of this dune complex are numerous elongated scars. These relict scars document a geomorphically distinct earthflow event. Arroyos that cut into flow scars expose eolian earthflow sediment overlying lacustrine deposits. In the zone of depletion, erosional-flow …

The Geology And Structural Significance Of The Arch Mountain Area, Northern Black Mountains, Mohave County, Arizona, Edward Eschner

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Arch Mountain area of northwestern Mohave County, Arizona, is typified by rocks that range from Precambrian to Quatemary in age. Arch mountain is a north-trending horst bounded on the west by the Petroglyph Wash graben and on the east by the Virgin Basin. A low-angle normal fault, herein named the Arch Mountain detachment fault, is exposed for 6 km along strike just below the ridge crest of Arch Mountain, and it is typified by a 2-20 cm thick zone of hematite-impregnated breccia and cataclasite. The detachment fault places an upper plate of Precambrian gneiss, Paleozoic quartzite, shale and dolomite, …

Spring Flow In A Portion Of Grand Canyon National Park, Arizona, David Bruce Goings

UNLV Theses, Dissertations, Professional Papers, and Capstones

Hermit, Monument, Salt, and Horn Creeks flow through four side canyons of the Colorado River within the Grand Canyon. They lie just west of Grand Canyon Village on the south side of the canyon. Each of these creeks is fed by at least one spring.

Comparisons of flow at each of these springs for a 14 month period, and precipitation on the south rim show a close correlation. The lag period between recharge at the rim and discharge at the springs is less than one month for Hermit Creek and between one and two months for the other three creeks. …

Provenance And Description Of Landslide Masses, Rainbow Gardens, Clark County, Nevada, Joseph R. Parolini

UNLV Theses, Dissertations, Professional Papers, and Capstones

A landslide breccia of plutonic and metamorphic rocks located 20 km east of Las Vegas, Nevada is interstratified with the late Tertiary Thumb Formation. Rock types of similar mineral composition to the landslide masses in the Rainbow Gardens are found 60 km to the east in the Gold Butte (Nevada) area. The landslide masses were displaced into their present position by lateral strike-slip motion along either the left-lateral Lake Mead fault system or the right-lateral Las Vegas shear zone. In the Rainbow Gardens landslide masses, five plutonic rock types, including Rapakivi granite, match rocks from the Gold Butte area, both …

Provenance And Description Of Landslide Masses, Rainbow Gardens Clark County, Nevada., Joseph R. Parolini

UNLV Theses, Dissertations, Professional Papers, and Capstones

A landslide breccia of plutonic and metamorphic rocks located 20 km east of Las Vegas, Nevada is interstratified with the late Tertiary Thumb Formation. Rock types of similar mineral composition to the landslide masses in the Rainbow Gardens are found 60 km to the east in the Gold Butte (Nevada) area. The landslide masses were displaced into their present position by lateral strike-slip motion along either the left-lateral Lake Mead fault system or the right-lateral Las Vegas shear zone. In t.he Rainbow Gardens landslide masses, five plutonic rock types, including rapakivi granite, match rocks from the Gold Butte area, both …

Geology And Ore Deposits Of The Johnnie District, Nye County, Nevada, Stanley Wayne Ivosevic

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Johnnie district, in the northwestern Spring Mountains, Nye County, Nevada, may have produced a little under 100,000 troy oz of gold, since the discovery of the district in 1890.

An approximately 13,000-ft-thick (4,000 m) section of east-dipping upper Precambrian through Middle Cambrian miogeosynclinal clastic and carbonate rocks is exposed in the district. The strata are, in order of decreasing age, the Johnnie Formation, Stirling Quartzite, Wood Canyon Formation, Zabriskie Quartzite, and Carrara and Bonanza King Formations. These are overlain by Cenozoic units which include and older unit and a younger unit of fanglomerate, the older containing a megabreccia deposit, …

Stratigraphic Comparison Of The Precambrian Wyman And Johnnie Formations In The Western Great Basin, California, Johnnie Nathan Moore

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Precambrian Johnnie Formation in the Death Valley area and to the south is separable into two facies. The southern facies contains six distinct members: the transitional, quartzite, lower carbonate-bearing, siltstone, upper carbonate-bearing, and Rainstorm members. Dolomite, quartzite, and mudstone characterize the southern facies, as does the presence of the Johnnie oolite. To the north the Johnnie oolite pinches out and the amount of mudstone in the formation increases. The dominantly mudstone northern facies contains local gray limestone lenses closely similar to limestone in the Wyman Formation in the White-Inyo Mountains. Generally outcrops of the northern facies of the Johnnie …

The Structural And Metamorphic History Of The Oakhurst Roof Pendant, Mariposa And Madera Counties, California, Lee R. Russell

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Oakhurst roof pendant, near Oakhurst, California, consists of three pre-Cretaceous clastic metasedimentary rock units, surrounded and intruded by rocks of the Sierra Nevada batholith. Two zones of probable "sheared granitic" and "ultramafic" rocks trend northwesterly and are approximately aligned with the Foothills fault system farther north.

The dominant mesocopic feature of the pendant is a northwesterly striking foliation which forms a downward converging fan. Earlier-formed hornblende lineations have been transposed into this foliation plane, as shown by Schmidt-net projections.

Rocks comprising the three unites show three textural stages:

1) Early amphiboles and diopside overgrown by later static amphibole pophyroblasts. …

Late Cenozoic Geomorphic History Of Lee Canyon, Spring Mountains, Nevada, John Henry Gucwa

UNLV Theses, Dissertations, Professional Papers, and Capstones

Located in the west central portion of Clark County, Nevada, the Spring Mountain Range borders the western edge of the Las Vegas Valley. Within the mountain range, a fault block, there are several canyons whose geomorphic history is closely related to the geomorphic history of the major alluvial fans which flank the mountains. Lee Canyon, which is the study area is one of these canyons. In Lee Canyon is preserved a complex canyon fill which has been subjected to several periods of down-cutting and valley-widening. The details of the canyon's geomorphic history recorded by filling and fill removal has not …

Ground Water Flow Systems Of Central Nevada, G. William Fiero Jr

UNLV Theses, Dissertations, Professional Papers, and Capstones

The U.S. Atomic Energy Commission has been evaluating a large area of central Nevada in order to define a supplemental test site for the underground testing of high-yield nuclear devices. Safety considerations involving the radiocontamination of the ground water in the vicinity of the test site necessitated that research be conducted to determine the direction and rate of flow of the ground water. This investigation defines the ground water flow systems in eighteen valleys comprising 12,000 square miles of central Nevada.

The definition of the systems was made following a compilation of existing hydrologic and geologic data for the area. …

Surficial Geology Of The Las Vegas Quadrangle, Nevada, Charles Edgar Price Jr

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Las Vegas 15-minute quadrangle, located in the south part of the state of Nevada, includes about 240 square miles in and around the city of Las Vegas; it is in the basin and range province. The quadrangle includes a broad valley floor that was once a lake bottom, a bordering area of badlands and rolling hills developed in Tertiary and Quaternary deposits, an outer marginal area of alluvial fans, and the surrounding mountains.

The mountains constitute about three per cent of the total land surface and are composed of rock ranging in are from Precambrian to Tertiary. The remainder …

Geology Of The White Pine District, Fred L. Humphrey

UNLV Theses, Dissertations, Professional Papers, and Capstones

The White Pine district of Nevada is about 30 miles east of Eureka, midway between eureka and Ely, and includes approximately 270 square miles. the area comprises essentially the southeast quarter of the Seligman No. 1 quadrangle, the southwest quarter of the Illipah No. 2 quadrangle, the northwest quarter of the Treasure Hill quadrangle, and the northeast quarter of the Mount Hamilton quadrangle in T. 15, 16, 17, N., and R. 57, 58 E., M.D.B. and M.

The original purpose of the geological work, done under the direction of the Nevada Bureau of Mines, was to prepare a map of …