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Articles 1081 - 1110 of 1546
Full-Text Articles in Earth Sciences
The Effects Of Fractures On The Occurrence And Distribution Of Arsenic In The Upper Floridan Aquifer During Aquifer Storage And Recovery, William Charles Hutchings
The Effects Of Fractures On The Occurrence And Distribution Of Arsenic In The Upper Floridan Aquifer During Aquifer Storage And Recovery, William Charles Hutchings
USF Tampa Graduate Theses and Dissertations
ABSTRACT
Aquifer storage and recovery (ASR) is used world-wide to supplement available water supplies by storing surplus water in aquifers and recovering it during periods of drought and increased demand. The use of ASR as an option for increasing available municipal irrigation and fresh water supplies is threatened as a result of the mobilization of arsenic in some aquifers during ASR. Arsenic is liberated from arsenic-bearing sulfide minerals as a result of the mixing of oxidizing injected water with reducing insitu groundwater. Fracture networks can have significant influence on the migration and distribution of arsenic in the Upper Floridan Aquifer …
A Geochemical Analysis Of Fulgurites: From The Inner Glass To The Outer Crust, Michael L. Joseph
A Geochemical Analysis Of Fulgurites: From The Inner Glass To The Outer Crust, Michael L. Joseph
USF Tampa Graduate Theses and Dissertations
Cloud-to-ground lightning strikes produce natural glasses on the surface of the Earth, called fulgurites. These natural glasses are tubular in shape with a central void surrounded by an inner glass, and the inner glass is surrounded by an outer crust or toasted region. Previous studies report different kinds of melts existing in several different types of fulgurites; however, little to no chemical data has been collected that tracks chemical variations from the inner glass to the outer crust of a fulgurite. This study uses microprobe and laser ablation inductively coupled plasma mass spectrometer analytical techniques to collect transects of chemical …
Speciation And Removal Mechanisms Of Rhenium In Anoxic Waters: Roles Of Zero-Valent Sulfur, Mineral Oxide Catalysis, And Pyrite Surfaces, Trent P. Vorlicek
Speciation And Removal Mechanisms Of Rhenium In Anoxic Waters: Roles Of Zero-Valent Sulfur, Mineral Oxide Catalysis, And Pyrite Surfaces, Trent P. Vorlicek
All Private Grants
Global warming is expected to intensify the effects of coastal anoxia. Knowledge of the causes of geohistorical anoxic episodes may prove critical in developing strategies for the mitigation of or adaptation to the consequences of climate change upon the global aquatic environment. The geochemistry of Re provides the means to acquiring this knowledge. Within oxic waters, Re exists as geochemically-inert ReO4-. Under reducing conditions, Re is removed from the aqueous phase and deposited in sediments. Unfortunately, an incomplete understanding of Re geochemistry hampers exploitation of Re as a paleoredox indicator. Authors purport Re sequestration begins in suboxic environments; others produce …
A Study Of Enhanced De-Chlorination And Bio-Remediation: Molasses Injections Into Groundwater, Brent Anderson
A Study Of Enhanced De-Chlorination And Bio-Remediation: Molasses Injections Into Groundwater, Brent Anderson
Natural Resources Management and Environmental Sciences
No abstract provided.
Estimating Land Surface Temperature Using A Thermal Sharpening Technique, Yitong Jiang, Qihao Weng
Estimating Land Surface Temperature Using A Thermal Sharpening Technique, Yitong Jiang, Qihao Weng
Symposium 2012
No abstract provided.
A Mineralogical Textural And Chemical Characterization Of A Hypothesized Kimberlite At White Mountain, Sunlight Basin, Wyoming, Stuart Kenderes
A Mineralogical Textural And Chemical Characterization Of A Hypothesized Kimberlite At White Mountain, Sunlight Basin, Wyoming, Stuart Kenderes
Mahurin Honors College Capstone Experience/Thesis Projects
Geologists have examined the causes and mechanisms responsible for the Heart Mountain detachment for over a century with much debate and discussion. White Mountain is a part of the upper plate, which was emplaced during the detachment event. Within White Mountain, there exist several andesitic dikes and carbonate ultra-cataclasite injectites, which were integral in the emplacement of the Heart Mountain detachment. This research involves the characterization and identification of an enigmatic vertical outcropping of brecciated rock located on White Mountain, Sunlight Basin, Wyoming, which was originally interpreted as a kimberlite. Samples were collected for geochemical and textural comparison, and cut …
Deciphering The Evolution Of Ore Fluids At The Batu Hijau Copper-~Gold Porphyry Deposit, Sumbawa, Indonesia, Jordan Thomas Armstrong
Deciphering The Evolution Of Ore Fluids At The Batu Hijau Copper-~Gold Porphyry Deposit, Sumbawa, Indonesia, Jordan Thomas Armstrong
UNLV Theses, Dissertations, Professional Papers, and Capstones
Fluid inclusions contained within quartz veins from the Batu Hijau Cu-Au porphyry deposit in Indonesia were analyzed to track the evolution of fluid temperature, pressure, and composition during the formation of the deposit to better understand the formation of this and other Cu-Au porphyry deposits in order aid future exploration. A combination of petrography, microthermometry, synchrotron x-ray fluorescence, and laser ablation-inductively coupled plasma-mass spectrometry were used to determine the temperature, pressure, and compositional aspects of the deposit.
Four types of fluid inclusions were recognized at Batu Hijau based on the volume percent of the vapor bubble; inclusions were classified as …
Evaluating Recharge And Dynamics Of Flow In The Lower Virgin River Basin, Usa: Interpretation Of Hydrochemical And Stable Isotopic Data, Joseph Asante
Evaluating Recharge And Dynamics Of Flow In The Lower Virgin River Basin, Usa: Interpretation Of Hydrochemical And Stable Isotopic Data, Joseph Asante
UNLV Theses, Dissertations, Professional Papers, and Capstones
Because of the complex geologic setting of the Basin and Range province, groundwater flow systems of the Intermountain basins of the southwestern United States are complex and remain poorly understood. Understanding these flow systems is important for water budgeting on a regional and local scale, and development of robust numerical groundwater models for sustainable water use and protection of water-dependent ecosystems. Although for decades hydrochemistry and isotopes have been used to characterize and trace subsurface water and surface water, effectively interpreting these data are still challenging, which can be attributed to existing subjective grouping of these data and the lack …
Chemical Weathering Of The Mafic Minerals Serpentine And Olivine In Natural Environments, Julie Lynn Baumeister
Chemical Weathering Of The Mafic Minerals Serpentine And Olivine In Natural Environments, Julie Lynn Baumeister
UNLV Theses, Dissertations, Professional Papers, and Capstones
Chemical weathering is a critical process that plays a key role in controlling the chemistry of natural waters, the cycling of atmospheric carbon dioxide, and the formation of soil. The weathering of silicate minerals is important because the Earth's crust is composed of approximately 92 weight percent silicate minerals. Despite an extensive literature on mineral dissolution and kinetics, relatively few studies have examined weathering of the mafic minerals serpentine and olivine, especially in a natural environment. The first chapter of this thesis provides an introduction to the minerals serpentine and olivine. The second chapter of this thesis examines the important …
The Behavior Of Zircon During Partial Melting In Anatectic Migmatites: Insights To Metamorphism, Deformation And Tectonism In The Central Santa Fe Range, Northern New Mexico, Michelle Renee Stropky
The Behavior Of Zircon During Partial Melting In Anatectic Migmatites: Insights To Metamorphism, Deformation And Tectonism In The Central Santa Fe Range, Northern New Mexico, Michelle Renee Stropky
UNLV Theses, Dissertations, Professional Papers, and Capstones
Three lithologic assemblages exposed in the central Santa Fe Range, northern New Mexico include (1) a septum of Proterozoic low temperature (~700oC, 5.5 kbars), semi-pelitic anatectic migmatites surrounded by (2) deformed megacrystic biotite granite that is intruded by (3) discrete plutons of largely undeformed hornblende biotite tonalite. Metamorphic fabrics in the migmatite record three deformation events (D1 - D3); a composite S1/S2 fabric (D1 and D2) that formed contemporaneous with anatexis and is folded about a southwest plunging map-scale (D3) antiform. The megacrystic granite exhibits a pervasive S1 subsolidus foliation that parallels the S1/S2 fabric in the migmatite and is …
Bulk Rock Composition And Geochemistry Of Olivine-Hosted Melt Inclusions In The Grey Porri Tuff And Selected Lavas Of The Monte Dei Porri Volcano, Salina, Aeolian Islands, Southern Italy., Angela L. Doherty, Robert J. Bodnar, Benedetto De Vivo, Wendy A. Bohrson, Harvey E. Belkin, Antonia Messina, Robert J. Tracy
Bulk Rock Composition And Geochemistry Of Olivine-Hosted Melt Inclusions In The Grey Porri Tuff And Selected Lavas Of The Monte Dei Porri Volcano, Salina, Aeolian Islands, Southern Italy., Angela L. Doherty, Robert J. Bodnar, Benedetto De Vivo, Wendy A. Bohrson, Harvey E. Belkin, Antonia Messina, Robert J. Tracy
All Faculty Scholarship for the College of the Sciences
The Aeolian Islands are an arcuate chain of submarine seamounts and volcanic islands, lying just north of Sicily in southern Italy. The second largest of the islands, Salina, exhibits a wide range of compositional variation in its erupted products, from basaltic lavas to rhyolitic pumice. The Monte dei Porri eruptions occurred between 60 ka and 30 ka, following a period of approximately 60,000 years of repose. The bulk rock composition of the Monte dei Porri products range from basaltic-andesite scoria to andesitic pumice in the Grey Porri Tuff (GPT), with the Monte dei Porri lavas having basaltic-andesite compositions. The typical …
Reservoir Potential Of Sands Formed In Glaciomarine Environments: An Analog Study Based On Cenozoic Examples From Mcmurdo Sound, Antarctica, Christopher R. Fielding, Brian A. Blackstone, Tracy D. Frank, Zi Gui
Reservoir Potential Of Sands Formed In Glaciomarine Environments: An Analog Study Based On Cenozoic Examples From Mcmurdo Sound, Antarctica, Christopher R. Fielding, Brian A. Blackstone, Tracy D. Frank, Zi Gui
Department of Earth and Atmospheric Sciences: Faculty Publications
This paper provides documentation of unexpectedly high-reservoir-quality glaciomarine sands found in the Cenozoic succession beneath McMurdo Sound, Antarctica, as an analogue study for evaluations of hydrocarbon prospectivity in basins elsewhere. The Oligocene to Lower Miocene succession of the Victoria Land Basin, an extant portion of the West Antarctic Rift System, comprises diamictites, mudrocks, and sandstones with minor conglomerates. These lithologies are arranged in repetitive stacking patterns (cycles), interpreted to record repeated advance and retreat of glaciers into and out of the basin, with attendant eustatic and isostatic effects. Phases of ice retreat within the cycles comprise an array of mudrocks, …
Surficial Redistribution Of Fallout 131iodine In A Small Temperate Catchment, Joshua D. Landis, Nathan T. Hamm, Carl E. Renshaw, W. Brian Dade, Francis J. Magilligan, John D. Gartner
Surficial Redistribution Of Fallout 131iodine In A Small Temperate Catchment, Joshua D. Landis, Nathan T. Hamm, Carl E. Renshaw, W. Brian Dade, Francis J. Magilligan, John D. Gartner
Dartmouth Scholarship
Isotopes of iodine play significant environmental roles, including a limiting micronutrient (127I), an acute radiotoxin (131I), and a geochemical tracer (129I). But the cycling of iodine through terrestrial ecosystems is poorly understood, due to its complex environmental chemistry and low natural abundance. To better understand iodine transport and fate in a terrestrial ecosystem, we traced fallout 131iodine throughout a small temperate catchment following contamination by the 11 March 2011 failure of the Fukushima Daiichi nuclear power facility. We find that radioiodine fallout is actively and efficiently scavenged by the soil system, where it …
Geochemical And Strontium Isotope Characterization Of Produced Waters From Marcellus Shale Natural Gas Extraction, Elizabeth C. Chapman, Rosemary C. Capo, Brian W. Stewart, Carl S. Kirby, Richard W. Hammack, Karl T. Schroeder, Harry M. Edenborn
Geochemical And Strontium Isotope Characterization Of Produced Waters From Marcellus Shale Natural Gas Extraction, Elizabeth C. Chapman, Rosemary C. Capo, Brian W. Stewart, Carl S. Kirby, Richard W. Hammack, Karl T. Schroeder, Harry M. Edenborn
Faculty Journal Articles
Extraction of natural gas by hydraulic fracturing of the Middle Devonian Marcellus Shale, a major gas-bearing unit in the Appalachian Basin, results in significant quantities of produced water containing high total dissolved solids (TDS). We carried out a strontium (Sr) isotope investigation to determine the utility of Sr isotopes in identifying and quantifying the interaction of Marcellus Formation produced waters with other waters in the Appalachian Basin in the event of an accidental release, and to provide information about the source of the dissolved solids. Strontium isotopic ratios of Marcellus produced waters collected over a geographic range of ∼375 km …
Size And Exhumation Rate Of Ultrahigh-Pressure Terranes Linked To Orogenic Stage, Andrew R.C. Kylander-Clark, Bradley R. Hacker, Chris G. Mattinson
Size And Exhumation Rate Of Ultrahigh-Pressure Terranes Linked To Orogenic Stage, Andrew R.C. Kylander-Clark, Bradley R. Hacker, Chris G. Mattinson
All Faculty Scholarship for the College of the Sciences
A growing set of data indicates a stark contrast between the evolution of two types of ultrahigh-pressure (UHP) terranes: large terranes that evolved slowly (over 10–30 Myr), and small terranes that formed and were exhumed on timescales of < 10 Myr. Here we compare the characteristics – area, thickness, formation rate, exhumation rate, age, and tectonic setting – of these two endmember types of UHP terrane worldwide. We suggest that the two UHP terrane types may form during different orogenic stages because of variations in the buoyancy and traction forces due to different proportions of subducting crust and mantle lithosphere or to different rates of subduction. The initial stages of continent collision involve the subduction of thin continental crust or microcontinents, and thus tectonic forces are dominated by the density of the oceanic slab; subduction rates are rapid and subduction angles are initially steep. However, as collision matures, thicker and larger pieces of continental material are subducted, and the positive buoyancy of the down-going slab becomes more prominent; subduction angles become gentle and convergence slows. Assessing the validity of this hypothesis is critical to understanding the physical and chemical evolution of Earth's crust and mantle.
Included here is the post-print copy of this article. The final publication is available via ScienceDirect at http://www.sciencedirect.com/science/article/pii/S0012821X11007564
Geochemical Classification Of Placer And Lode Gold Deposits Within The Northern Dome Rock Mountains Of The Quartzsite Mining District, Az, Christina Marie Lopez Velasquez
Geochemical Classification Of Placer And Lode Gold Deposits Within The Northern Dome Rock Mountains Of The Quartzsite Mining District, Az, Christina Marie Lopez Velasquez
Theses Digitization Project
In this study the geochemistry and distribution of placer and lode gold deposits of the northern Dome Rock Mountains near Quartzsite, Arizona wre studied. The primary objectives of this study were to geochemically classify the placer and lode gold deposits of the Quartzsite Mining District, Arizona. Additional objectives were to determine estimates of the economic value and quantity of production of placer and lode gold deposits. Addressing the economic geology of placer gold deposits, the ultimate goal for this geochemical study is to determine the source(s) of the placer gold and determining the economic potential.
A Five-Year Analysis Of Carbon Stock Plots In The Gordon Natural Area’S Big Woods, Cathy Spahr, Chad Hudson, Andy Tamez
A Five-Year Analysis Of Carbon Stock Plots In The Gordon Natural Area’S Big Woods, Cathy Spahr, Chad Hudson, Andy Tamez
Forest Carbon Storage Study Documents
No abstract provided.
Geology Of National Parks Modules For The Spreadsheets Across The Curriculum Library, H. L. Vacher, Thomas C. Juster, Judy Mcllrath, Mark Rains
Geology Of National Parks Modules For The Spreadsheets Across The Curriculum Library, H. L. Vacher, Thomas C. Juster, Judy Mcllrath, Mark Rains
Geology Faculty Publications
No abstract provided.
Evolution With Depth From Detrital To Authigenic Smectites In Sediments From And-2a Drill Core (Mcmurdo Sound, Antarctica), Francesco Iacoviello, Giovanna Giorgetti, Fernando Nieto, Isabella Turbanti Memmi
Evolution With Depth From Detrital To Authigenic Smectites In Sediments From And-2a Drill Core (Mcmurdo Sound, Antarctica), Francesco Iacoviello, Giovanna Giorgetti, Fernando Nieto, Isabella Turbanti Memmi
ANDRILL Research and Publications
We have examined the nature and origin of smectites in glaciomarine sediments of the AND-2A drill core (McMurdo Sound, Antarctica) by means of X-ray diffraction (XRD) analyses on the clay fraction, field emission scanning electron microscopy (FESEM), scanning electron microscopy (SEM) observations and SEM-EDS microanalyses on smectite particles. Relying on the smectite variation throughout the drill core it was possible to split the sequence into three units. Smectites throughout the core are either detrital or authigenic. Detrital smectites are close to montmorillonite-beidellite in composition while newly-formed smectites frequently have higher Fe-Mg contents and intermediate compositions between the saponite and nontronite …
Isotope Geochemistry And Geochronology Of Lavas From The Line Islands Chain, Central Pacific Basin: Insight Into The Origin Of The Line Islands, Lauren Storm
Open Access Theses & Dissertations
Geochemical compositions of melts produced in the Earth's mantle provide key data for understanding Earth's internal structure. Particularly, the compositions of unusually large outpourings of basaltic lavas in large igneous provinces involve substantial source volumes, thereby contributing to our understanding of mantle structure and dynamics. Although the origin of such lavas remains enigmatic, geochemically they may originate from Earth's oldest and deepest mantle reservoir, transported by a mantle plume or by entrainment in passive upwelling beneath a fast spreading center. The Pacific Ocean basin hosts several large igneous provinces that formed near a triple junction of three oceanic plates, and …
Assessing Delta Oxygen-18 In The Coral Genus Isopora For Reconstructing Indo-Pacific Regional And Seasonal Climate, Gavin Lemley
Assessing Delta Oxygen-18 In The Coral Genus Isopora For Reconstructing Indo-Pacific Regional And Seasonal Climate, Gavin Lemley
Legacy Theses & Dissertations (2009 - 2024)
Paleoclimate reconstructions often utilize coral reefs with very long time spans such as the genus Porites and Diploastrea, because of their potential to provide centuries of continuous climate records via geochemical signatures. Smaller corals, such as the genus Isopora, have been essentially unexplored as climate archives because their small skeletons (<1 m) and short lifespans (years to decades) do not provide such continuous geochemical records. There has not been a practical application for such corals until recently. In early 2010, the Integrated Ocean Drilling Program Leg 325 (IODP-325) cored drowned fossil reefs off the Great Barrier Reef (GBR) with the objectives of reconstructing sea level and surface ocean conditions since the Last Glacial Maximum. Out of 213 massive fossil corals that were recovered, most were massive Isoporan colonies. A 30-specimen subset of these fossils range in age from ~32,000 to ~11,500 years before present with even temporal spacing, based on preliminary U/Th dating of core catcher samples. This age distribution is excellent for meeting IODP-325 objectives, but the suitability of Isopora for paleoclimate analyses remains unknown.
Assessing The Reproducibility Of Coral Oxygen And Carbon Isotope Time Series From Fiji And Tonga And Their Application To The Reconstruction Of South Pacific Convergence Zone Movements Since The Mid-1800s, Emilie Pauline Dassie
Assessing The Reproducibility Of Coral Oxygen And Carbon Isotope Time Series From Fiji And Tonga And Their Application To The Reconstruction Of South Pacific Convergence Zone Movements Since The Mid-1800s, Emilie Pauline Dassie
Legacy Theses & Dissertations (2009 - 2024)
A major feature affecting the hydrology of the southern hemisphere is the South Pacific Convergence Zone (SPCZ); a band of high rainfall extending southeastward from the Western Pacific Warm Pool (WPWP). It is a key source of atmospheric water vapor and latent heating. While it is clear that the SPCZ plays a fundamental role in Earth's climate, little is known about the patterns and mechanisms responsible for interannual to century-scale changes in its position and how it may respond to global climate change.
Assessment Of Coal Geology, Resources, And Reserves In The Montana Powder River Basin, Jon E. Haacke, David C. Scott, Lee M. Osmonson, James A. Luppens, Paul E. Pierce, Jay A. Gunderson
Assessment Of Coal Geology, Resources, And Reserves In The Montana Powder River Basin, Jon E. Haacke, David C. Scott, Lee M. Osmonson, James A. Luppens, Paul E. Pierce, Jay A. Gunderson
United States Geological Survey: Publications
The purpose of this report is to summarize geology, coal resources, and coal reserves in the Montana Powder River Basin (MTPRB) assessment area in southeastern Montana. This report represents the fourth assessment area within the Powder River Basin to be evaluated in the continuing U.S. Geological Survey regional coal assessment program.
There are four active coal mines in the MTPRB assessment area: the Spring Creek and Decker Mines, both near Decker; the Rosebud Mine, near Colstrip; and the Absaloka Mine, west of Colstrip. During 2011, coal production from these four mines totaled approximately 36 million short tons (MST). A fifth …
The Evolution Of Grenville Basement In The Eastern Great Smoky Mountains; Constraints From U-Pb Zircon Geochronology, Whole Rock Sm-Nd, And Feldspar Pb Geochemistry, Ryan Joel Quinn
Theses and Dissertations--Earth and Environmental Sciences
Identifying the crustal affinity of Grenville basement rocks in the Dellwood quadrangle, western NC, provides insight into the tectonic evolution of eastern Laurentia during Grenville orogenesis. U-Pb zircon geochronology of orthogneiss, augen gneiss, and mafic xenoliths in orthogneiss reveal magmatic pulses at 1130, 1180, and 1330 Ma and metamorphic episodes at 450 and 1040 Ma. Xenoliths in 1330 Ma orthogneiss are as old as 1382 Ma and represent the oldest component of Blue Ridge basement identified to-date. Feldspar Pb isotope values span a range between juvenile-Laurentian and southern-central Appalachian basement/Amazonia. Most Pb isotope data define an array consistent with crustal …
A New Phase Speciation Leaching Procedure For The Determination Of Metals In Oxic And Anoxic Sediments, Brandon R. Gipson
A New Phase Speciation Leaching Procedure For The Determination Of Metals In Oxic And Anoxic Sediments, Brandon R. Gipson
OES Theses and Dissertations
Toxic trace elements such as cadmium, lead, chromium, and arsenic released by human activities can accumulate in marine and estuarine sediments, where these metals are often sequestered until local environmental changes (e.g., redox, salinity, and/or pH) allow these elements to be reintroduced into the food web. In order to assess the extent of toxic trace element contamination in sediment, numerous leaching schemes have been developed that separate sediment-bound trace metals into operationally defined geochemical phases. These "phase speciation" leaching schemes are typically designed with the purpose of being used on either oxic or anoxic sediments. However, natural sediments often contain …
Atr-Ftir Studies On The Kinetics Of Dimethylarsinic Acid (Dma) Surface Complexation With Iron(Oxyhydr)Oxides, Julia Tofan-Lazar Miss
Atr-Ftir Studies On The Kinetics Of Dimethylarsinic Acid (Dma) Surface Complexation With Iron(Oxyhydr)Oxides, Julia Tofan-Lazar Miss
Theses and Dissertations (Comprehensive)
Dimethylarsinic acid (DMA) is an organoarsenical compound that, along with monomethylarsonic acid, poses a health and an environmental risk, and a challenge to the energy industry. Little is known about the surface chemistry of DMA at the molecular level with materials relevant to geochemical environments and industrial sectors. The surface chemistry of phosphorus and arsenic compounds in their organic and inorganic forms is of great interest due to its role in controlling their transport, bioaccessibility and speciation. This thesis reports the first in-situ and surface-sensitive rapid kinetic studies on the adsorption and desorption of DMA to and from Fe-(oxyhydr)oxide films …
Stable Isotope Analysis Of Busycon Sinistrum To Determine Fort Walton-Period Seasonality At St. Joseph Bay, Northwest Florida, Ryan Michael Harke
Stable Isotope Analysis Of Busycon Sinistrum To Determine Fort Walton-Period Seasonality At St. Joseph Bay, Northwest Florida, Ryan Michael Harke
USF Tampa Graduate Theses and Dissertations
ABSTRACT
Recent archaeological investigations indicate that coastal Fort Walton cultures in the St. Joseph Bay region of northwest Florida emphasized marine and estuarine foraging. These late prehistoric (A.D. 1000-1500) peoples collected fish, shellfish, and other aquatic resources. At the Richardson's Hammock site (8Gu10), radiocarbon-dated to about A.D. 1300, as at dozens of other shell middens around this salty bay, large gastropods were a major subsistence component. This adaptation is in sharp contrast with that of contemporaneous inland Fort Walton societies, who relied on maize agriculture. It is unknown whether coastal groups represent separate hunter-gatherer-fisher populations or seasonal migrations by inland …
Identifying And Tracking Proteins Through The Marine Water Column: Insights Into The Inputs And Preservation Mechanisms Of Protein In Sediments, Eli K. Moore, Brook L. Nunn, David R. Goodlett, H. Rodger Harvey
Identifying And Tracking Proteins Through The Marine Water Column: Insights Into The Inputs And Preservation Mechanisms Of Protein In Sediments, Eli K. Moore, Brook L. Nunn, David R. Goodlett, H. Rodger Harvey
OES Faculty Publications
Proteins generated during primary production represent an important fraction of marine organic nitrogen and carbon, and have the potential to provide organism-specific information in the environment. The Bering Sea is a highly productive system dominated by seasonal blooms and was used as a model system for algal proteins to be tracked through the water column and incorporated into detrital sedimentary material. Samples of suspended and sinking particles were collected at multiple depths along with surface sediments on the continental shelf and deeper basin of the Bering Sea. Modified standard proteomic preparations were used in conjunction with high pressure liquid chromatography-tandem …
Scientific Drilling Of Speleothems – A Technical Note, Christoph Spötl, David Mattey
Scientific Drilling Of Speleothems – A Technical Note, Christoph Spötl, David Mattey
International Journal of Speleology
This short article provides detailed descriptions of custom-made and commercially available hand-held drilling gear and options for water-flushing units specifically designed to obtained good-quality core material from speleothems even in remote cave regions. We use small-diameter (6-7 mm) diamond drill bits to obtain aliquots of calcite (as little as a few hundreds of milligram) from the interior of the basal part of in-situ stalagmites. These small cores are used to date the onset of stalagmite growth and occasionally to obtain other compositional information. Larger diameter drill bits produce cores 25-32 mm in diameter and up to 1.3 m in length …
Gypsum-Carbonate Speleothems From Cueva De Las Espadas (Naica Mine, Mexico): Mineralogy And Palaeohydrogeological Implications, Fernando Gázquez, Jose Maria Calaforra, Paolo Forti, Fernando Rull, Jesús Martínez-Frías
Gypsum-Carbonate Speleothems From Cueva De Las Espadas (Naica Mine, Mexico): Mineralogy And Palaeohydrogeological Implications, Fernando Gázquez, Jose Maria Calaforra, Paolo Forti, Fernando Rull, Jesús Martínez-Frías
International Journal of Speleology
Some of the most outstanding hypogenic gypsum speleothems worldwide have been recently discovered in the Naica mines. The Cueva de las Espadas (Swords Cave), which lies at 120 m depth, hosts a rare type of speleothem called “espada” (“sword”). This study contributes to the understanding of the mineralogical composition of these singular speleothems, by means of their examination using micro-Raman spectroscopy, FT-IR spectroscopy and EDX microprobe. Our data revealed a complex mineralogy comprising a high-purity selenite core covered by several layers of calcite, aragonite and gypsum. Solid inclusions of polymetallic oxides (Mn-Pb-Zn) and graphite were also detected. The position of …