Mineral Physics Commons^™

The First Cave Occurrence Of Orpiment (As₂S₃) From The Sulfuric Acid Caves Of Aghia Paraskevi (Kassandra Peninsula, N. Greece), Georgios Lazaridis, Vasilios Melfos, Lambrini Papadopoulou

International Journal of Speleology

Orpiment, tamarugite and pickeringite occur in close association above the surface of thermal water cave pools in the active sulfuric acid caves of Aghia Paraskevi on the Kassandra peninsula, northern Greece. Gypsum also occurs as small interstitial crystals or encrustations. Orpiment is of high significance since it has not previously been reported as a cave mineral. In addition, tamarugite and pickeringite rarely occur in karst caves. Water from a borehole and a spring is of Na-Cl type and contains traces of CO₂ and H₂S. The B/Cl ratios indicate seawater participation with a possible mixing with geothermal water …

Trace Element And Stable Isotope Data From A Flowstone In A Natural Cave Of The Mining District Of Sw Sardinia (Italy): Evidence For Zn²⁺-Induced Aragonite Precipitation In Comparatively Wet Climatic Conditions, Guglielmo Angelo Caddeo, Jo De Waele, Franco Frau, Loren Bruce Railsback

International Journal of Speleology

A speleothem from Crovassa Azzurra, a mine cave in SW Sardinia (Italy), has been analysed for mineralogy, minor and trace elements and stable isotopes. It is composed of layers of primary calcite and aragonite, with a region of secondary calcite. The primary carbonate is strikingly rich in Zn and Pb, presumably as the result of transport in solution from overlying Pb-Zn deposits. Immediately below the transition between calcite and aragonite, concentrations of Zn, Cd and P increase. At the transition between aragonite and Pb-rich aragonite, concentrations of Pb and P increase. Stable isotopes indicate an evolution toward more humid periods …

2,2′,5,5′-Tetra­Chloro­Benzidine, Onome Ugono, Marcel Douglas, Nigam Rath, Alicia Beatty

Chemistry & Biochemistry Faculty Works

In the crystal structure of the title compound, C12H8Cl4N2, mol­ecules lie on crystallographic twofold axes at the centre of the C-C bonds linking the benzene rings, such that the asymmetric unit consists of a half-mol­ecule. The individual mol­ecules participate in inter­molecular N-H...N, N-H...Cl, C-H...Cl and Cl...Cl [3.4503 (3) Å] inter­actions.

High Pressure Structural Studies On Eus Nano Particles Up To 52 Gpa, Kristie Canaday, Ravhi S. Kumar

Undergraduate Research Opportunities Program (UROP)

Crystal size reduction in bulk materials changes the structural and magnetic properties considerably [1]. More importantly the transition pressure is strongly influenced by temperature, pressure, and the crystallite size effect. Rare earth europium chalcogenides crystallize in the NaCl (rock salt) type structure. The interest in Eu nanomaterials is motivated by the possibility of their use in magnetic devices [2,3]. Recent studies suggest that europium chalcogenide nanocrystals exhibit significant changes in their structural and magnetic properties, compared to bulk chalcogenides, when the nanocrystal diameter decreases. The crystal structure and phase transition behavior of EuS nanoparticles have been investigated and compared as …

Determination Of Olivine Orientation Dependence Through Raman Spectroscopy, Alexandra J. Leandre, Joseph Lussier, Brittany Morgan, Michael Rodriguez

Undergraduate Research Opportunities Program (UROP)

Raman spectra were taken of olivine for analysis of vibrational energy intensity ratios. This allowed for determination of its crystal orientation. Garnet inclusions in peridotite were mapped and Raman spectra were taken for these as well. The inclusions could not identified, and data from the Raman spectra proved inconclusive due to difficulty in removing background signal.

Detrital Zircon Geochronology For Neoproterozoic To Cambrian Sediment Sources Of The Deep Creek Range And The Pilot Range In The Southwestern United States, Kaysea Perry

Earth and Soil Sciences

Detrital zircon studies of miogeoclinal sediments can help provide a deeper look into the mechanisms leading to continental breakup by studying the evolution of the continental margin of North America. Few detrital zircon studies have been conducted to support previous research and theories about the sedimentation of the Miogeocline from the Neoproterozoic to the Cambrian. Studies targeted at the Basin and Range province of the western United States show a trend of increasing local sediment sources. We analyzed detrital zircons from the Pilot and Deep Creek Ranges in Nevada and Utah via LA-MC-ICP-MS at the University of Arizona LaserChron Center …

Fluid Budget Of Metasedimentary Rocks From A Tertiary Accretionary Prism And Connections To Seismicity, Olympic Peninsula, Northwest Washington State, Holly Makena Macfadden Rotman

All Master's Theses

Metamorphic dehydration reactions and fluid movement in accretionary prisms have been linked to the recently discovered episodic tremor and slip (ETS) earthquake events along subduction zones, but prior studies lack the detail to effectively test the hypothesis that fluid flow triggers ETS events. I conducted field work along a 52.5 km transect on the Olympic Peninsula metasedimentary accretionary prism of the Cascadia subduction zone, and collected approximately 40 representative samples of sandstone and mudrock that were buried to 6–15 km. This depth range intersects the 10–50 km depth range of ETS events. My objectives are to quantify the water flow …

Using Conservative And Biological Tracers To Better Understand The Transport Of Agricultural Contaminants From Soil Water Through The Epikarstic Zone, Brian Ham

Masters Theses & Specialist Projects

Agriculture contamination is very common in karst systems due to the vulnerability of these aquifers. Animal waste is often spread across crop land to enrich the soil with nitrates and phosphates. Herbicides and pesticides are also applied to the crops. The transport of these pollutants through the soil and epikarst is a difficult process to monitor due to the complex, heterogeneous behavior of the groundwater as it makes its way down to the aquifer below.

An experimental site at Crumps Cave lended a unique opportunity to monitor the vadose zone at a waterfall in the cave below. A previous dye …

X-Ray Diffraction Study Of Dysprosium Single Crystal Samples In A Diamond Anvil Cell (Dac), Ognjen Grubor-Urosevic

UNLV Theses, Dissertations, Professional Papers, and Capstones

X-ray diffraction is the basis of crystallography, the study of the structure of crystals. It uses X-rays of a wavelength on the order of the size of atoms, so it can resolve the positions of individual atoms in a crystal. Illuminating the crystal with a well-collimated X-ray beam produces X-rays diffracted in a certain direction for a specific crystal orientation. By analyzing the relative phase of the incoming and outgoing scattered X-rays, the unique arrangements of atoms can be determined and the structure of the crystal can be solved.

There is a long standing controversy regarding the crystal structures and …

High Pressure Phase Transistions In The Lanthanide Sesquioxides, Jason Patrick Mcclure

UNLV Theses, Dissertations, Professional Papers, and Capstones

Crystallizing into 5 known polymorphic forms, the rare-Earth sesquioxides RE 2 O 3 represent a family of 4-f electron compounds that have been the subject of study for many years. Aspects of the systematics in the structural phase transitions for RE 2 O 3 (RE=La, Sm, Eu, Gd, Y, Er, Yb, Lu) under pressure were studied using diamond anvil cells (DACs). As a part of this study, detailed equation of state (EOS) data for all these compounds were obtained through the use of angle-dispersive x-ray diffraction (XRD) where anomalies in compression data led to the detailed investigation into one particular …

Magnetic Ordering Phase Transitions Of Gd2sn2o7, Gordon Tam, Andrew Cornelius, Daniel Antonio

Undergraduate Research Opportunities Program (UROP)

Pyrochlores with magnetic rare earth ions are a topic of interest due to unusual results brought about by their high degree of geometrical frustration. The lattice structure prevents the magnetic spin interactions from finding a single minimum energy state, which leads to a nonzero residual entropy[1]. By analyzing the heat capacity at low temperatures, the type of magnetic interaction can be determined and the temperatures at which long-range magnetic ordering and magnetic field induced splitting of energy states occur.

Modeling The Deformation Of Fayalite, Greg Hoth, Mike Brawner, Pamela Burnley

Undergraduate Research Opportunities Program (UROP)

We are studying how the mineral fayalite deforms under stress while it is subject to high pressures and temperatures. Specifically, we are analyzing x-ray diffraction spectra obtained from experiments with the D-DIA apparatus at Brookhaven national labs. By fitting peaks to the diffraction spectra, we can calculate the spacing between lattice planes of fayalite and so we can observe how this spacing changes over time as the crystal structure deforms We hope to show that this deformation can be modeled using an Elastic Plastic Self Consistent model. In such a model, the material is treated as a cluster of independently …

A New Method Of Synthesizing Black Birnessite Nanoparticles: From Brown To Black Birnessite With Nanostructures, Shizhi Qian, Marcos A. Cheney, Pradip K. Bhowmik, Sang W. Joo, Wensheng Hou, Joseph M. Okoh

Mechanical Engineering Faculty Research

A new method for preparing black birnessite nanoparticles is introduced. The initial synthesis process resembles the classical McKenzie method of preparing brown birnessite except for slower cooling and closing the system from the ambient air. Subsequent process, including wet-aging at 7◦C for 48 hours, overnight freezing, and lyophilization, is shown to convert the brown birnessite into black birnessite with complex nanomorphology with folded sheets and spirals. Characterization of the product is performed by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), thermogravimetric analysis (TGA), and N2 adsorption (BET) techniques. Wet-aging and lyophilization times are shown to …

Thermochronological Evolution Of Calcite Formation At The Potential Yucca Mountain Repository Site, Nevada: Part 2 Fluid Inclusion Analyses And Upb Dating, Jean S. Cline, Amy J. Smiecinski, Robert Bodnar

Publications (YM)

The presence of two-phase fluid inclusions in thin secondary mineral crusts at the potential Yucca Mountain nuclear waste repository has raised questions regarding the origin, timing, and temperature of past fluid flow through the repository horizon. The geologically recent passage of fluids with high temperatures would call into question the suitability of the site for the storage of high level nuclear waste. This study determined the thermal history of fluid flow through the site using fluid inclusion analyses and constrained the timing of thermal fluids by dating silica minerals spatially associated with the fluid inclusions using U-Pb techniques. Results provide …

Thermochronological Evolution Of Calcite Formation At The Proposed Yucca Mountain Repository Site, Nevada: Part 1, Secondary Mineral Paragenesis And Geochemistry, Jean S. Cline, Amy J. Smiecinski, Robert Bodnar

Publications (YM)

In the near future a decision will be made as to whether or not Yucca Mountain, 90 miles northwest of Las Vegas, Nevada is a suitable site for a permanent, underground, high level nuclear waste repository. A major factor in determining the suitability of Yucca Mountain as a repository is the potential for the site to be flooded by water during the regulatory lifetime. The current study was undertaken to examine the past fluid history at the site, to gain a better understanding of the possibility of flooding in the near geologic future. To estimate the past fluid flux into …

Analysis Of Lunar Basalt Flows In Oceanus Procellarum Using Clementine Data, Noel William Jackson

OES Theses and Dissertations

Remote sensing analyses of data set taken by Clementine in 1994 permit new observations about mineral distribution on the lunar surface, basalt flow stratigraphy, and thus the geologic evolution of the Moon. The northern section of Oceanus Procellarum contains numerous impact craters which penetrated the basalt and thus can be used as natural probes to estimate the number and thicknesses of flows.

I constructed a mosaic taken in three frequencies ( 415 nm, 750 nm, 950 nm), and a Ratio Image (750/415 = red, 750/950 = green, 415/750 = blue). On such an image, red indicates the iron-poor mature highland …

Microanalytical Investigations Of Gold-Bearing Rocks From The An Najadi Region In Saudi Arabia, Nazrul I. Khandaker, M. Ahmed, M. M. Hariri, M. A. Garwan, K. R. Khan, M. M. Al-Ohali

Publications and Research

The Proton Induced X-ray Emission technique with a scanning microbeam (micro-PIXE) and Scanning Electron Microscopy (SEM) were employed to study gold-bearing rocks from the An Najadi and adjacent regions situated within the exposed northeastern part of the Arabian Shield. These microanalytical investigations, together with routine petrological and ore microscopic studies, demonstrated the presence of important partitioning of major minerals and trace elements in several samples. These measurements also revealed microstructural features including brecciation within quartz grains and metal concentrations within these fracture-controlled micro-conduits. Results showed promise in terms of using distinctive geochemical signatures for ore body recognition. Of particular interest …

Study Of Volcanic Sediments By Microbeam-Pixe Technique, Nazrul I. Khandaker, M. Ahmed, M. A. Garwan

Publications and Research

Single mineral grains in a suite of Cretaceous (85–90 Ma) volcanic sedimentary rocks were analyzed using the microbeam-PIXE technique to understand fundamental geological processes responsible for micro-scale variation in elemental composition across mineral zones, twinning, cleavage planes, fractures and grain boundaries. Distributions of major and trace elements show distinct geochemical features indicative of a specific geological setting and a subsequent diagenetic process in these volcanic sediments. Examples of mineral zoning, microstructures of variable chemistry and post-depositional fluid flow are discussed using the data on feldspar group of minerals.

Comments On “Measurements Of 7Be And 210Pb In Rain, Snow, And Hall”, M. Baskaran

Environmental Science and Geology Faculty Research Publications

No abstract available

A Search For The Seasonal Variability On The Depositional Fluxes Of 7Be And 210Pb, M. Baskaran

Environmental Science and Geology Faculty Research Publications

Investigations of the atmospheric fallout of ⁷Be and ²¹⁰Pb in many places around the globe indicate that there are seasonal variations on the depositional fluxes of these nuclides: high in winter in a few places, while in most places the high occurs in spring. However, these earlier studies did not address quantitatively the corresponding seasonal variations of the amount of precipitation during these periods. Data on the depositional fluxes of ⁷Be and ²¹⁰Pb in Galveston, Texas, during the years 1989–1991 indicate that the seasonal variation is not uniform from year to year, and the amount of …

Speleothems As Proxy For The Carbon Isotope Composition Of Atmospheric Co2, M. Baskaran, R. V. Krishnamurthy

Environmental Science and Geology Faculty Research Publications

We have measured the stable isotope ratios of carbon in a suite of recent cave deposits (<200 >years) from the San Saba County, Texas, USA. The methodology for dating these deposits using excess ²¹⁰Pb was recently established [Baskaran and Iliffe, 1993]. The carbon isotope ratios of these samples, spanning the time period ∼1800–1990 AD, reflect the carbon isotope ratio of atmospheric CO₂ for the same period. The pathways by which the δ¹³C of atmospheric CO₂ is imprinted on these speleothems can be explained using a model developed by Cerling (1984). The results suggest that the …

Atmospheric Depositional Fluxes Of 7Be And 210Pb At Galveston And College Station, Texas, M. Baskaran, Charles H. Coleman, Peter H. Santschi

Environmental Science and Geology Faculty Research Publications

The bulk depositional fluxes of ²¹⁰Pb and ⁷Be were measured at a coastal (Galveston) and an inland (College Station) station for about 3 years, between 1989 and 1991. The annual depositional fluxes of ⁷Be and ²¹⁰Pb at Galveston during this period varied by a factor of about 2.5, between 8.9 and 23.2 disintegrations per minute (dpm) cm⁻² yr⁻¹, with a mean of 14.7 dpm cm⁻² yr⁻¹ for ⁷Be, and 0.67 and 1.71 dpm cm⁻² yr⁻¹, with a mean of 1.03 dpm cm⁻² yr⁻¹ for ^{210 …}

Age Determination Of Recent Cave Deposits Using Excess 210Pb - A New Technique, M. Baskaran, Thomas M. Iliffe

Environmental Science and Geology Faculty Research Publications

Cave deposits have been widely used as proxy recorders in deciphering palaeoclimate during the last glacial/interglacial maxima (∼ 120 ka) [Harmon et al., 1975; Atkinson et al., 1978; Goede and Harmon, 1983; Ayliffe and Veeh, 1989]. Palaeoclimatic studies of cave deposits for the past 1–1000 yr time scale require a precise dating technique, that until now has been lacking. Due to the multiple sources of carbon in speleothems, ¹⁴C dates obtained for recently deposited calcite are highly variable and thus, ¹⁴C dating techniques are not suitable to obtain speleothem ages for the past 1–1000 years.

Here, we show …

Fluid Inclusion Studies Of The Morefield Pegmatite Amelia County, Virginia, John Richard Smerekanicz

OES Theses and Dissertations

The Morefield Pegmatite is a planar, nearly vertical body situated in Grenville age gneisses and schists in the southeast Piedmont of Virginia. It consists of a mineralogically simple albite-quartz outer zone and a texturally and mineralogically complex inner zone of microcline-topaz-quartz, with trace amounts of rare-element minerals. Fluid inclusions in samples of quartz, topaz, beryl, spessartite and albite that span the length, width and depth of both zones can be classified by chemical composition into two main groups: H₂O-rich solutions and CO₂- H₂O -rich fluids. The H₂O -rich inclusions consist of H …

Mineralogy, Geochemistry, And Dispersal Of Opaque Oxides On The Continental Shelf Of The Cascadia Margin, Kommajosyula Subramanya Ravi

Dissertations and Theses

Opaque oxide minerals (ilmenite, chromite, and magnetite) in sands from the Oregon continental shelf have been studied to establish the provenance, dispersal, and grade of potential shelf placer deposits. The study area extends southward from offshore of the Columbia River in northern Oregon to the Klamath River in northern California.

Contributions To The Quaternary Geology Of Northern Maine And Adjacent Canada, J. Steven Kite (Ed.), Thomas V. Lowell (Ed.), Woodrow B. Thompson (Ed.)

Maine Collection

Contributions to the Quaternary Geology of Northern Maine and Adjacent Canada

Bulletin 37 - Maine Geological Survey, Department of Conservation,

Augusta, Maine 04333 (1988).

Contents: Introduction / A GEOMORPHIC METHOD FOR RECONSTRUCTING PALEO ICE SHEETS, Part I: GLACIAL GEOLOGY. - T. Hughes and J. Fastook / A GEOMORPHIC METHOD FOR RECONSTRUCTING PALEO ICE SHEETS, Part II: GLACIOLOGY. - J. Fastook and T. Hughes / TILL STRATIGRAPHY AT THE BALD MOUNTAIN MINE SITE, NORTHERN MAINE - W. R. Holland and F. F. Bragdon / GLACIAL DISPERSAL FROM THE PRIESTLY LAKE AND DEBOULLIE PLUTONS, NORTHERN MAINE - E. F. Halter / GLACIATION …

Metasomatism Between Amphibolite And Metaultramafic Rocks During Upper Amphibolite Facies Metamorphism, Tobacco Root Mountains, Southwest Montana, William Robert Mcculloch

Dissertations and Theses

The purpose of this study is to characterize the metasomatism that has taken place as a result of the chemical incompatibility between mafic and metaultramafic bulk compositions during high-grade regional metamorphism in the Tobacco Root Mountains, southwest Montana. Metasomatism of these rocks took place by both diffusionand infiltration-dominated processes. The result of these processes are characterized mineralogically and geochemically in the rocks.

Textural And Mineralogical Characteristics Of Altered Grande Ronde Basalt, Northeastern Oregon : A Natural Analog For A Nuclear Waste Repository In Basalt, Paul M. Trone

Dissertations and Theses

Altered flows that are low-MgO chemical types of the Grande Ronde Basalt crop out in the steep walls of the Grande Ronde River canyon near Troy, Wallowa County, Oregon. The alteration effects in these flows are being investigated as a natural analog system to a high level nuclear waste repository in basalt. The flows within the study are referred to as the analog flow, in which the alteration effects are the strongest, and the superjacent flow. The analog flow crops out at Grande Ronde River level and a roadcut-outcrop is developed in the flow-top breccia of this flow. The two …

The Geology And Hydrothermal Alteration Of The Bear Creek Butte Area, Crook County, Central Oregon, Richard Matthew Wilkening

Dissertations and Theses

The Eocene Clarno Formation, the Oligocene John Day Formation and basalts of the High Lava Plains are exposed in the Bear Creek Butte area in Central Oregon. In this area the Clarno Formation can be divided into a lower sequence composed of intermediate lava flows with intercalated mudflows and volcaniclastic sediments and an upper sequence of rhyolite and basalt flows and felsic ruffs. Separating the two units is a well developed saprolite. The change from intermediate to rhyolite-basalt volcanism reflects a change in the tectonic environment of the Cascade volcanic arc from compression to relaxation as subduction of the Farallon …

Rock Phosphates : Fertilisers For Sandy Soils?, J S. Yeates, D. M. Deeley, G. T.B. Cockerton, M. F. Clarke

Journal of the Department of Agriculture, Western Australia, Series 4

Rock phosphates, from which water solubls phosphorus fertilisers such as superphosphate are manufactured, sometimes appear attractive to farmers because of their relatively low cost. But redearch has shown t6hat on most western australian soils they are not economical fertilisers. However, some deep sandy soils of the State's high rainfall area are exeptions. On these soils, rock phosphates compare favourably with superphosphate for plant growth. But how can these deep sands be identified.

This article describes research to define the soil characteristics necessary for rock phosphates and fertilisers containing rock phosphate, such as Coastal superphosphate, to be effective substitutes for superphosphate.