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Articles 61 - 90 of 94
Full-Text Articles in Mineral Physics
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
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
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 …
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 …
Magnetic Ordering Phase Transitions Of Gd2sn2o7, Gordon Tam, Andrew Cornelius, Daniel Antonio
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.
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
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 …
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
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
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
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
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
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 …200>
Atmospheric Depositional Fluxes Of 7Be And 210Pb At Galveston And College Station, Texas, M. Baskaran, Charles H. Coleman, Peter H. Santschi
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
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
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
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.)
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
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
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 …
Depositional Model For The Auriferous Gravels In The Payan Mining District Department Of Narino, Columbia, South America, Jim R. Garrett
Depositional Model For The Auriferous Gravels In The Payan Mining District Department Of Narino, Columbia, South America, Jim R. Garrett
OES Theses and Dissertations
Unlike placer deposits in arid and semi-arid environments where gold concentration is closely tied to the position of the bedrock, Payan placer deposits have no association with bedrock. Gold concentration values show highest gold concentrations occur at the contact of a coarse sand unit and its underlying gravel unit. Comparisons of the size and shape distributions of gold grain populations with their associated black sand populations indicate the gold and black sand were not deposited in hydraulic equilibrium. The mean size of each gold population is consistently coarser than the mean size of its associated black sand population despite the …
Tourmaline - A Prospecting Guide For Massive Base-Metal Sulfide Deposits In The Penobscot Bay Area, Maine, John F. Slack
Tourmaline - A Prospecting Guide For Massive Base-Metal Sulfide Deposits In The Penobscot Bay Area, Maine, John F. Slack
Maine Collection
Tourmaline - A Prospecting Guide for Massive Base-Metal Sulfide Deposits in the Penobscot Bay Area, Maine
by John F. Slack, U.S. Geological Survey
Special Economic Studies Series No.8
Maine Geological Survey, Department of Conservation, Augusta, Maine (June, 1980).
Contents: Abstract / Introduction / Geologic Setting / Massive Sulfide Deposits / Tourmaline Occurrences / Tourmaline: A Guide to Ore / Acknowledgements / References Cited
Petrology Of The Rockport Quarry Limestone (Middle Devonian Traverse Group) Alpena, Presque Isle And Montmorency Counties, Michigan, Charles Willard Cookman
Petrology Of The Rockport Quarry Limestone (Middle Devonian Traverse Group) Alpena, Presque Isle And Montmorency Counties, Michigan, Charles Willard Cookman
Masters Theses
The basal unit of the dominantly carbonate Traverse Group, the Bell Shale, is gradationally overlain by the Rockport Quarry Limestone which has a thickness of approximately 14 m. The Rockport Quarry Limestone is composed of a dark unrestricted marine subtidal organic-mud packstone facies, comprised of an algal-mat-bearing coral packstone subfacies and a shallower water crinoid-bryozoan grainstone subfacies; a shoal forming stromatoporoid biolithite facies; and a lagoonal micrite facies comprised of a subtidal dense subfacies containing gastropods, ostracods, and calcispheres, and an Intertidal to supratidal fenestral subfacies. The local facies tract reconstructed for the Rockport Quarry Limestone is interpreted to be …
Maine Gems And Gem Minerals, Maine State Museum
Maine Gems And Gem Minerals, Maine State Museum
Maine Collection
Maine Gems and Gem Minerals
The Maine State Museum - Printed under Appropriation No. 1741.1
Sections Include : "An Introduction to the Gemstones of Maine", "Tourmaline", "Beryl", "Quartz Family Gems", "Topaz", "Gold", "Miscellaneous Gem Varieties", "Maine's 'Lost' Gem Mines", "Hamlin Necklace", etc
Native Indiana Iron Ores And 19th Century Ironworks, William J. Wayne
Native Indiana Iron Ores And 19th Century Ironworks, William J. Wayne
Department of Earth and Atmospheric Sciences: Faculty Publications
Introduction / 1
Phase one: Charcoal and native ores / 4
Northern Indiana ironworks and the postglacial bog ores / 4
Southern Indiana ironworks, Pennsylvanian and Mississippian ores / 10
Phase two: Block coals and Missouri ores / 15
Selected bibliography / 21
"The coming of iron manufacturers into the Indiana field should be encouraged. The reopening of ore deposits, the development of the coal fields, the building of furnaces within the state to smelt northern ores, the building of new railroads, and the extension of others, and the aggressive policy of existing roads to encourage industries along their lines, …
A Detailed Economic Investigation Of Geochemical And Aeromagnetic Anomalies North Central Maine, W. F. Stickney, R. S. Young, L. A. Wing
A Detailed Economic Investigation Of Geochemical And Aeromagnetic Anomalies North Central Maine, W. F. Stickney, R. S. Young, L. A. Wing
Maine Collection
A Detailed Economic Investigation of Geochemical and Aeromagnetic Anomalies North Central Maine
W.F.Stickney, R.S.Young and L.A.Wing
Special Economic Series No.4, Maine Geological Survey, Department of Economic Development, Augusta, Maine (March 1965).
Contents: Foreword / Part I - Geology (W.F. Stickney) / Part II - Geophysics (R.S. Young) / Part III - Geochemistry (L.A. Wing) / References
Report On Some Iron And Nickel Minerals From The Soapstone Deposits Of Saline County, Arkansas, Phillip Wicklein, Alden B. Carpenter
Report On Some Iron And Nickel Minerals From The Soapstone Deposits Of Saline County, Arkansas, Phillip Wicklein, Alden B. Carpenter
Journal of the Arkansas Academy of Science
No abstract provided.
Trace Elements For Cereal Crops And Pastures, Edgar Noel Fitzpatrick
Trace Elements For Cereal Crops And Pastures, Edgar Noel Fitzpatrick
Journal of the Department of Agriculture, Western Australia, Series 4
TRACE element deficiencies are widespread in Western Australia and application of copper, zinc, molybdenum and cobalt have played a major part in land development in this State.
Research Officer E. N. Fitzpatrick, M.Sc. (Agric.) reviews recent Department of Agriculture research on the use of Trace elements for crop and pasture growth on deficient soils in Western Australia.
Applying Copper And Zinc Fertilizers To Cereals, H M. Fisher
Applying Copper And Zinc Fertilizers To Cereals, H M. Fisher
Journal of the Department of Agriculture, Western Australia, Series 4
Most light soils with a sandy or gravelly surface are likely to need copper and zinc; heavier clay or loamy soils mostly do not.
Petrology Of The Precambrian Rocks Of Part Of The Monte Largo Area, Nm, Paul Wayne Lambert
Petrology Of The Precambrian Rocks Of Part Of The Monte Largo Area, Nm, Paul Wayne Lambert
Earth and Planetary Sciences ETDs
Approximately 7 to 8 square miles of Precambrian rocks are exposed in the vicinity of the Monte Largo Hills in north-central New Mexico. The Precambrian rocks are bounded mainly by Pennsylvanian sedimentary rocks in both fault and noncomformable contact.
The area is made up largely of quartz-feldspar gneiss, hornblende gneiss, and quartzite. Quartz-feldspar gneiss is the most abundant rock type. Mica schist and sillimanite hornfels occur in minor amounts. Other Precambrian rocks include medium-grained granite, splite and pegmatite dikes, and quartz veins. A minor amount of migmatite is present as a result of the intimate association of quartz-feldspar gneiss and …
Genetic Study Of Some Pyrrhotite Deposits Of Maine And New Brunswick, Dept. Of Development Of Industry And Commerce
Genetic Study Of Some Pyrrhotite Deposits Of Maine And New Brunswick, Dept. Of Development Of Industry And Commerce
Maine Collection
Genetic Study of Some Pyrrhotite Deposits of Maine and New Brunswick
by Robert S. Houston
Maine Geological Survey - Bulletin 7
Department of Development of Industry and Commerce, Augusta, Maine (January, 1956).
Contents: Abstract / Introduction / Field and Laboratory Studies / Regional Geography / Regional Geology / Pyrrhotite Deposits / Description of Individual Deposits / Literature Cited
Anisotropism In Garnets, Arthur B. Merkle
Anisotropism In Garnets, Arthur B. Merkle
Earth and Planetary Sciences ETDs
Six anisotropic garnets are studied by optical, thermal, and X-ray diffraction methods in an attempt to determine the cause of anisotropism. The garnets are all ungrandites with compositions ranging from chromian grossularite to nearly pure andradite, the composition having been estimated from indices of refraction and unit cell dimensions. In all cases the birefringence is 0.004 or less. Both positive and negative uniaxial and biaxial figures are sometimes observed. Heating of the garnets at 900°C for periods of 96 to 264 hours reduced the anisotropism in five of the six garnets studied; this observation is in agreement with previously reported …