Geochemistry Commons^™

Middle Crustal Ductile Deformation Patterns In Southern Tibet: Insights From Vorticity Studies In Mabja Dome, Jackie Langille

All Master's Theses

Mabja Dome, southern Tibet, exposes mid-crustal rocks proposed to have originated from a southward flowing mid-crustal channel. Kinematic, mean kinematic vorticity (Wm), and metamorphic petrography analyses on these mid-crustal rocks were performed to test this hypothesis. Kinematic indicators show a transition with structural depth from top-north and top-south shear to solely top-south shear. Along the northernmost transects, Wm in schists and orthogneisses range from 0.52–0.84 (63–36% pure shear). Wm for quartzites ranges from 0.9–0.99 (27–1% pure shear). Deformation temperatures increase from ~450 °C in the chloritoid-zone to ~700 °C in the sillimanite-zone and were recorded between ~35–16 Ma. These patterns …

Origin And Paleoclimatic Significance Of Late Quaternary Loess In Nebraska: Evidence From Stratigraphy, Chronology, Sedimentology, And Geochemistry, Daniel R. Muhs, E. Arthur Bettis Iii, John N. Aleinikoff, John P. Mcgeehin, Jossh Beann, Gary Skipp, Brian D. Marshall, Helen M. Roberts, William C. Johnson, Rachel Benton

United States Geological Survey: Staff Publications

Loess is one of the most extensive surficial geologic deposits in mid-continental North America, particularly in the central Great Plains region of Nebraska. Last-glacial-age loess (Peoria Loess) reaches its greatest known thickness in the world in this area. New stratigraphic, geochronologic, mineralogic, and geochemical data yield information about the age and provenance of Peoria Loess, as well as evaluation of recent climate models.

Adsorption Of Lead On Single And Mixed Solid Systems, Soumya Das

Dissertations

Metal oxy-hydroxides and phyllosilicate minerals play a significant role in the fate and transport of heavy metals in the environment (Bertsch and Seaman, 1999). Chemical speciation of metals affects their bioavailability and chemical reactivity (Stumm and Morgan, 1996). Surface complexation models (SCMs) based on equilibrium thermodynamic principles have been successfully used to quantify adsorption of heavy metals on pure solid minerals, including phyllosilicates and oxy-hydroxides. For natural sediments with mixed mineralogy, Davis et al. (1998) suggested two different SCM approaches, namely, the component additivity and generalized composite models. In this study, adsorption of lead on pure HFO, silica and kaolinite …

Geogram 2007, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Shallow Slab Fluid Release Across And Along The Mariana Arc-Basin System: Insights From Geochemistry Of Serpentinized Peridotites From The Mariana Fore Arc, Ivan P. Savov, Jeffrey G. Ryan, Massimo D'Antonio, Patricia Fryer

Geology Faculty Publications

Shallow slab devolatilization is not only witnessed through fluid expulsion at accretionary prisms, but is also evidenced by active serpentinite seamounts in the shallow fore-arc region of the Mariana convergent margin. Ocean Drilling Program (ODP) Leg 195 recovered serpentinized peridotites that present a unique opportunity to study the products of shallow level exchanges between the upper mantle and slab-derived fluids. Similar to samples recovered during ODP Leg 125, the protoliths of these fore-arc serpentinized peridotites are mantle harzburgites that have suffered large volume melt extraction (up to 25%) prior to interactions with fluids released from the downgoing Pacific Plate. Samples …

Contact Metamorphism In The Malashan Dome, North Himalayan Gneiss Domes, Southern Tibet: An Example Of Shallow Extensional Tectonics In The Tethys Himalaya, Tetsuo Kawakami, Mutsuki Aoya, Simon Wallis, Jeffrey Lee, Kentaro Terada, Yu Wang, Matt Heizler

All Faculty Scholarship for the College of the Sciences

Combined petrographic, structural and geochronological study of the Malashan dome, one of the North Himalayan gneiss domes, reveals that it is cored by a Miocene granite, the Malashan granite, that intruded into the Jurassic sedimentary rocks of Tethys Himalaya. Two other granites in the area are referred to as the Paiku and Cuobu granites. New zircon SHRIMP U-Pb and muscovite and biotite ⁴⁰Ar-³⁹Ar dating show that the Paiku granite was emplaced during 22.2–16.2 Ma (average 19.3 ± 3.9 Ma) and cooled rapidly to 350–400 °C at around 15.9 Ma. Whole-rock granite chemistry suggests the original granitic magma …

Effect Of Regional Tectonic Setting On Local Fault Response To Episodes Of Volcanic Activity, Diana C. Roman, Philip Heron

Geology Faculty Publications

In this study we examine the interaction of tectonic and volcanically-generated stress fields, and their combined effect on patterns of volcanotectonic (VT) seismicity, by calculating Coulomb stress changes on local faults induced by a constant dike inflation event in a background stress field of systematically varying magnitude and orientation. We find that patterns of VT seismicity (earthquake locations and fault-plane solutions) resulting from dike inflation depend strongly on the relative strength and orientation of background tectonic stresses. Patterns of VT seismicity similar to those predicted by our Coulomb stress models have been observed at several recently active volcanoes, and appear …

Along-Strike Trace Element And Isotopic Variation In Aleutian Island Arc Basalt: Subduction Melts Sediments And Dehydrates Serpentine, Brad S. Singer, Brian R. Jicha, William P. Leeman, Nick W. Rogers, Matthew F. Thirlwall, Jeffrey G. Ryan, Kirsten E. Nicolaysen

Geology Faculty Publications

Trace element and Sr-Nd-Pb isotope compositions of basaltic lavas from 11 volcanoes spanning 1300 km of the Aleutian Island arc provide new constraints on the recycling of elements in melts and fluids derived from subducted oceanic crust and sediment. Despite a nearly twofold variation in the flux of sediment subducted along the Aleutians, proxies indicating the presence of sediment melt in the magma source, including Th/La and Th/Nd, do not vary systematically along strike. In contrast, ratios including B/La, B/Nb, B/Be, Cs/La, Pb/Ce, and Li/Y suggest that the quantity or composition of fluid transferred from the slab into the mantle …

High Crystallinity Si-Ferrihydrite: An Insight Into Its Neel Temperature And Size Dependence Of Magnetic Properties, Thelma S. Berquo, Subir K. Banerjee, Robert G. Ford, R. Lee Penn, Thomas Pichler

Geology Faculty Publications

Ferrihydrite, an antiferromagnetic iron oxyhydroxide with resulting magnetization due to uncompensated spins, is of great importance for the cycling of many trace metals in the environment. Four ferrihydrite samples prepared with 1.3 to 3.5 wt% of Si at different synthesis temperatures (7.5°C, 22°C, 50°C, and 75°C) were studied by temperature-dependent hysteresis loops, ZFC/FC susceptibility curves, ac susceptibility and Mössbauer spectroscopy. The incorporation of Si into the ferrihydrite during synthesis changed the properties of this mineral. Interestingly, seven sharp lines were observed in the X-ray diffraction pattern of the ferrihydrite samples prepared at 50°C and 75°C. In general, both XRD and …

Interdecadal-Decadal Climate Variability From Multi-Coral Oxygen Isotope Records In The South Pacific Convergence Zone Region Since 1650ad, Peipei Zhang

Geology Theses and Dissertations

Annual average oxygen isotope (δ18O) time series from five coral cores collected from Fiji and Tonga are used to construct a Fiji-Tonga Interdecadal-Decadal Pacific Oscillation (F-TIDPO) index of low frequency (>9yr and <55yr) climate variability in this area back to 1650 A.D. Presently, both Fiji and Tonga are located in the South Pacific Convergence Zone (SPCZ) salinity front region where the Interdecadal Pacific Oscillation (IPO) variation is most pronounced. We first demonstrate the consistency between this F-T IDPO index and a MSL pressure-based SPCZ Position Index (SPI) (1891-2000), thus verifying the ability of coral δ18O to record past interdecadal-decadal climatic variations in this region back to 1891. The F-T IDPO index is then shown to be synchronous with the IPO index (1856-2000), suggesting that this coral-based index effectively represents the interdecadal-decadal scale climate variance back to 1650. The consistently anti-phase spectrums of the F-T five-coral composite and the interdecadal-decadal components in equatorial Pacific coral δ18O series from Maiana [Urban et al., 2000] and Palmyra [Cobb et al., 2001] suggest that the simultaneous eastern expansion (western contraction) of the eastern salinity front of Western Pacific Warm Pool (WPWP) occurs at the same time as the northeast (southwest) movement of the SPCZ during a positive IPO (negative IPO) phase.

Outcrop Analog For Lower Paleozoic Hydrothermal Dolomite Reservoirs, Mohawk Valley, Ny, Brian E. Slater

Geology Theses and Dissertations

Geochemical analysis and field relations of linear dolomite bodies occurring in outcrop in the Mohawk Valley of New York suggest that they have undergone significant fault-related hydrothermal alteration. The dolomite occurs in the Lower Ordovician Tribes Hill Formation, which is regionally an early Ordovician shaley limestone with patchy dolomitization. The outcrop has an en echelon fault, fracture, and fold pattern. A 3D ground penetrating radar survey of the quarry floor has helped to map out faults, fractures, anticlines, synclines and the extent of dolomitization. Most of the dolomitization occurs in fault-bounded synclines or “sags” flanked by anticlines. The dolomite structures …

Concentrations Of Metals In Aquatic Invertebrates From The Ozark National Scenic Riverways, Missouri, Christopher J. Schmitt, William G. Brumbaugh, John M. Besser, Thomas W. May

United States Geological Survey: Publications

This report summarizes the findings of a study conducted as a pilot for part of a park-wide monitoring program being developed for the Ozark National Scenic Riverways (ONSR) of southeastern Missouri. The objective was to evaluate using crayfish (Orconectes spp.) and Asian clam (Corbicula fluminea) for monitoring concentrations of metals associated with lead-zinc mining. Lead-zinc mining presently (2007) occurs near the ONSR and additional mining has been proposed. Three composite samples of each type (crayfish and Asian clam), each comprising ten animals of approximately the same size, were collected during late summer and early fall of 2005 …

High- And Ultrahigh-Pressure Metamorphism In The North Qaidam And South Altyn Terranes, Western China, Chris G. Mattinson, C. A. Menold, Jian-Xin Zhang, D. K. Bird

All Faculty Scholarship for the College of the Sciences

The North Qaidam and South Altyn terranes extend approximately 1000 km across the northern Tibetan Plateau, and five localities preserve evidence of Early Paleozoic high-pressure (HP) or ultrahigh-pressure (UHP) metamorphism, including the presence of coesite, coesite pseudomorphs, and diamond. A review of the geology, petrology, and geochronology collected over the past 10 years since these localities were discovered supports a correlation of the North Qaidam and South Altyn terranes, offset 350-400 km across the Altyn Tagh fault. Geochronology interpreted to reflect eclogite-facies metamorphism yields ages between 500 and 420 Ma; detailed geochronology from one locality supports a protracted (tens of …

Geogram 2006, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Sinkhole Structure Imaging In Covered Karst Terrain, Sarah E. Kruse, M. Grasmueck, Matthew Weiss, D. Viggiano

Geology Faculty Publications

Ground penetrating radar (GPR) and resistivity techniques have been widely used to map the locations of sinkholes in covered karst terrain. To determine whether a sinkhole is a likely preferential conduit for groundwater flow, however, requires higher-resolution imaging than that used in conventional sinkhole mapping surveys. Field observations combined with simulated surveys for a 15-m diameter 3-m deep sinkhole in west-central Florida are used to assess the resolution of GPR and resistivity surveys targeting the semiconfining unit that floors the sinkhole depression. 2D resistivity surveys clearly show the central depression as well as resistivity contrasts between the cover sediments within …

Results Of Chemical Analyses For Alcove 8/ Niche 3 Tracer Studies, Jeanette Daniels, Amy J. Smiecinski

Publications (YM)

This is the final report detailing the analyses performed under ORD-FY04-011 "Chemical Analyses for Alcove 8/Niche 3 Tracer Studies," The work was performed under The University and Community College System of Nevada (UCCSN) and the Department of Energy (DOE) Cooperative Agreement DE-FC28-04RW12232, This task provided method development and analytical support for the Alcove 8/Niche 3 Tracer Studies in the Exploratory Studies Facility (ESF). Concentrations of tracers as well as major anions and cations were reported for samples provided by Lawrence Berkeley National Laboratory (LBNL) and the US Geological Survey (USGS). Samples were analyzed using High Performance Liquid Chromatography (HPLC) and …

Origin Of Gabbroic Xenoliths Within The Lone Mountain Dacite Intrusion, Big Sky, Montana: A Field And Petrographic Analysis, Emily Clement

Undergraduate Review

No abstract provided.

The Sparrow Surface Water-Quality Model: Theory, Application And User Documentation, G. E. Schwarz, A. B. Hoos, R. B. Alexander, R. A. Smith

United States Geological Survey: Publications

SPARROW (SPAtially Referenced Regressions On Watershed attributes) is a watershed modeling technique for relating water-quality measurements made at a network of monitoring stations to attributes of the watersheds containing the stations. The core of the model consists of a nonlinear regression equation describing the non-conservative transport of contaminants from point and diffuse sources on land to rivers and through the stream and river network. The model predicts contaminant flux, concentration, and yield in streams and has been used to evaluate alternative hypotheses about the important contaminant sources and watershed properties that control transport over large spatial scales.

This report provides …

Field, Petrographic, And Geochemical Characteristics Of Price Creek, Russ Mccormack

Undergraduate Review

No abstract provided.

Thermochronology And Provenance Of The Yakutat Terrane, Southern Alaska Based On Fission-Track And U/Pb Analysis Of Detrital Zircon, Stephanie Ellen Perry

Geology Theses and Dissertations

Northward transport of the Yakutat terrane along the Transition and Queen Charlotte-Fairweather transform faults led to Neogene collision of the Yakutat terrane with the southern continental Alaska margin. Northward translation resulted in a stratigraphy that records the erosion of thermotectonic terranes along its path. The strata of the Yakutat terrane includes the Lower Oligocene to Lower Eocene Kulthieth Formation, the Upper Eocene to Lower Miocene Poul Creek Formation and the Miocene-Pleistocene Yakataga Formation. Detrital zircon fission-track (DZFT) ages from stratigraphically coordinated samples collected in the Northern Robinson Mountains yield provenance information of the units that can shed light on their …

Assessing The Paleoceanographic Potential Of The Coral Montipora Venosa At Fanning Atoll, Central Equatorial Pacific, Alexa Stolorow

Geology Theses and Dissertations

As interest in global climate change increases, so does the need for better and more extensive climate proxies. The central equatorial Pacific has been established as the region with the largest ENSO-related sea surface temperature (SST) and precipitation (PPT) anomalies, which are known to impact global interannual climate variability. To date, the coral genus Porites has been most commonly utilized for coral-based paleo-reconstructions of ENSO and lower frequency phenomena. However, due to questions of biological artifacts in coral, to more fully understand coral-based reconstruction, different coral genera need to be analyzed.
In this study, oxygen (δ18O) and carbon (δ13C) isotopic …

The Effects Of Land Use Changes On Soil Carbon In The Russian Steppe, Andrew M. Ratigliano

Geology Theses and Dissertations

Increasing atmospheric CO2 levels within the past few centuries have led to many studies about the global carbon cycle. An important aspect in balancing the modern global carbon budget revolves around a missing sink of carbon. It is thought that the carbon accumulation in soil may be a significant component in this loss. As changes in land use under natural conditions have increased over the years, it is not well understood how these changes may affect the soil carbon. A useful technique in determining these changes are with the use of archived samples. Within a Russian steppe preserve that has …

Geochronology And Tectonic Significance Of Middle Proterozoic Granitic Orthogneiss, North Qaidam Hp/Uhp Terrane, Western China, Chris G. Mattinson, Joseph L. Wooden, Juhn G. Liou, D. K. Bird, C. L. Wu

All Faculty Scholarship for the College of the Sciences

Amphibolite-facies para- and orthogneisses near Dulan, in the southeast part of the North Qaidam terrane, enclose minor ultra-high pressure (UHP) eclogite and peridotite. Field relations and coesite inclusions in zircons from paragneiss suggest that felsic, mafic, and ultramafic rocks all experienced UHP metamorphism and a common amphibolite-facies retrogression. Ion microprobe U–Pb and REE analyses of zircons from two granitic orthogneisses indicate magmatic crystallization at 927 ± Ma and 921 ± 7 Ma. Zircon rims in one of these samples yield younger ages (397–618 Ma) compatible with partial zircon recrystallization during in-situ Ordovician-Silurian eclogite-facies metamorphism previously determined from eclogite and paragneiss …

Spectral Analysis Of Ground Penetrating Radar Response To Thin Sedimentary Layers, Swagata Guha, Sarah E. Kruse, E. E. Wright, U. E. Kruse

Geology Faculty Publications

Ground penetrating radar (GPR) systems utilized in studies of sedimentary deposits generate wavelengths (tens of centimeters) that are commonly much longer than the thickness of bedding (often millimeters to centimeters) within the target strata. Where this is the case, radar profiles represent interference patterns. Simple models of radar response to sequences of thin beds such as those found in coastal deposits show potentially detectable spectral shifts toward higher frequencies in radar returns. Spectral analysis of radar data over barrier beach deposits at Waites Island, South Carolina, shows that returns from packages with heavy mineral laminations are shifted toward higher frequencies …

Tunnel Geology As Seen By Geologists: Manhattan, New York City, Nazrul I. Khandaker, Stanley Schleifer, Masud Ahmed, Alan R. Slaughter, Belal A. Sayeed, Dorean J. Flores, Mario Jo-Ramirez

Publications and Research

Current exploratory boring operations in and around Manhattan, New York City are providing geologists and geotechnical engineers with a plethora of new and interesting geological information, which has not been previously reported. The rocks encountered, mostly medium to high-grade metamorphic rocks, with both mafic and felsic intrusives, are highly variable in competency and mechanical durability. One of the most frequently encountered rock types is a garnetiferous-muscovite-biotite schist which grades into schistose gneiss and displays a wide variety of structural, compositional, and textural attributes. Metamorphic minerals showing the variable degree of metamorphism include graphite, talc, garnet, kyanite, tourmaline, emory, and occasionally …

Geogram 2005, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Modeling Tephra Sedimentation From A Ruapehu Weak Plume Eruption, Costanza Bonadonna, J. C. Phillips, B. F. Houghton

Geology Faculty Publications

We present a two-dimensional model for sedimentation of well-mixed weak plumes, accounting for lateral spreading of the cloud, downwind advection, increase of volumetric flux in the rising stage, and particle transport during fallout. The 17 June 1996 subplinian eruption of Ruapehu produced a bent-over plume that rose to a height of 8.5 km in a wind field with an average velocity of 24 m s⁻¹ and generated a narrow deposit on land extending up to 200 km from vent. The sedimentation from the Ruapehu plume was dominated by coarse ash, with all the blocks and most of the lapilli …

Geochemistry Of Serpentinized Peridotites From The Mariana Forearc Conical Seamount, Odp Leg 125: Implications For The Elemental Recycling At Subduction Zones, Ivan P. Savov, Jeffrey G. Ryan, Massimo D'Antonio, Katherine Kelley, Patrick Mattie

Geology Faculty Publications

Recent examinations of the chemical fluxes through convergent plate margins suggest the existence of significant mass imbalances for many key species: only 20–30% of the to-the-trench inventory of large-ion lithophile elements (LILE) can be accounted for by the magmatic outputs of volcanic arcs. Active serpentinite mud volcanism in the shallow forearc region of the Mariana convergent margin presents a unique opportunity to study a new outflux: the products of shallow-level exchanges between the upper mantle and slab-derived fluids. ODP Leg 125 recovered serpentinized harzburgites and dunites from three sites on the crests and flanks of the active Conical Seamount. These …

Sulfide Mineralization In Deep-Water Marine Sediments Related To Methane Transport, Methane Consumption, And Methane Gas Hydrates, Matthew K. Thompson, Walter S. Borowski, Charles K. Paull, William Ussler Iii

EKU Faculty and Staff Scholarship

Patterns of sulfide sulfur concentration and sulfur isotopic composition (d³⁴ S) are perhaps related to upward methane transport, especially in sediments underlain by methane gas hydrate deposits. Increased methane delivery augments the effect of anaerobic methane oxidation (AMO) occurring at the sulfate-methane interface (SMI). Sulfate and methane co-consumption results in production of dissolved sulfide at the interface that is eventually sequestered within sulfide minerals (elemental sulfur, iron monosulfide, pyrite).

We examine the sediments of two piston cores collected over the Blake Ridge gas hydrate deposits (offshore southeastern United States) by extracting total sedimentary sulfide using chromium reduction. We use …

Probabilistic Modeling Of Tephra Dispersal: Hazard Assessment Of A Multiphase Rhyolitic Eruption At Tarawera, New Zealand, Costanza Bonadonna, Charles B. Connor, B. F. Houghton, Laura Connor, Marc A. Byrne, A. Laing, T. K. Hincks

Geology Faculty Publications

The Tarawera Volcanic Complex comprises 11 rhyolite domes formed during five major eruptions between 17,000 B.C. and A.D. 1886, the first four of which were predominantly rhyolitic. The only historical event erupted about 2 km³ of basaltic tephra fall (A.D. 1886). The youngest rhyolitic event erupted a tephra fall volume more than 2 times larger and covered a wider area northwest and southeast of the volcano (∼A.D. 1315 Kaharoa eruption). We have used the Kaharoa scenario to assess the tephra fall hazard from a future rhyolitic eruption at Tarawera of a similar scale. The Plinian phase of this eruption …