Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Geochemistry

Environmental Sciences

Institution
Publication Year
Publication
Publication Type
File Type

Articles 1 - 30 of 60

Full-Text Articles in Physical Sciences and Mathematics

Heat Source-Related Mechanisms And Genetic Modes For The Formation Of Hot Dry Rocks In The Reshuiwei Geothermal Field, Hunan Province, Du Jiang, Cai Ningbo, Zhang Baojian, Wang Keying, He Lihong, Liao Fengchu Jan 2024

Heat Source-Related Mechanisms And Genetic Modes For The Formation Of Hot Dry Rocks In The Reshuiwei Geothermal Field, Hunan Province, Du Jiang, Cai Ningbo, Zhang Baojian, Wang Keying, He Lihong, Liao Fengchu

Coal Geology & Exploration

Hot springs with temperatures exceeding 90℃ indicate that the Reshuiwei geothermal field in Hunan Province enjoys sound geothermal geological conditions, making this geothermal field a potential favorable area for hot dry rock (HDR) exploration. To carry out a reasonable evaluation of the geothermal reservoir and prospects for exploration and exploitation of HDRs in the Reshuiwei geothermal field in the Rucheng area, this study comprehensively analyzed the deep geological structures, geochemical characteristics, geophysical characteristics including gravity, magnetic, electrical, and seismic properties, and geothermal field characteristics of the geothermal field. Furthermore, it revealed the deep thermal structures of the geothermal field from …


Environmental Fate Of Sulfur In Sulphur Creek, Valles Caldera, Nm: Implications For Metal Transport And Water Quality, Daniel Lavery Dec 2023

Environmental Fate Of Sulfur In Sulphur Creek, Valles Caldera, Nm: Implications For Metal Transport And Water Quality, Daniel Lavery

Earth and Planetary Sciences ETDs

The 1.2 Ma Valles Caldera in north-central New Mexico hosts a young igneous volcanic hydrothermal system after the model proposed in Goff and Janik (2000). The Sulphur Springs area within Valles Caldera is an acid-sulfate area typical of this model, discharging acidic waters (pH 1.5-3) formed by oxidation of magmatic H2S at the surface. We report on samples obtained from springs and streams collected between October 2021 and May 2023 in the Sulphur Creek and Alamo watersheds. Sulphur Creek receives input from Sulphur Springs and exhibits low pH (2-4) and high concentrations of Al (≤110 mg/L), Fe (≤60 …


Hydrothermal Carbonization Of Biomass Wastes: Sustainability And Geochemistry, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Ruben Forjan-Castro, José Luis Gallego Sep 2023

Hydrothermal Carbonization Of Biomass Wastes: Sustainability And Geochemistry, Michael A. Kruge, Teresa A. Centeno, Alvaro Amado-Fierro, José Manuel González-Lafuente, Ruben Forjan-Castro, José Luis Gallego

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Introduction. To reduce the stream of solid waste going to landfills, innovative means for beneficial use are essential. The diversity and volume of organic wastes pose singular problems and opportunities for recovery and circularity. Common processes for organics include conversion to biofuels and carbonization to biochar, typically done by torrefaction (dry pyrolysis). Research on biochar explores its potential as pollutant adsorbent, agricultural or polluted soil amendment, biofuel (directly or as feedstock), and for carbon sequestration (Ighalo et al., 2022; Cavali et al., 2023). Recently, other processes at lower temperatures such as hydrothermal carbonization (HTC) offer new possibilities (Seshadri et al., …


The Impact Of Glacial Proximity On The Elemental Composition Of Leachate Derived From Sediment Weathering, Karoline Ford May 2023

The Impact Of Glacial Proximity On The Elemental Composition Of Leachate Derived From Sediment Weathering, Karoline Ford

Theses/Capstones/Creative Projects

This study assesses chemical weathering trends as they relate to glacial retreat. The chemical environment of surfaces exposed to the atmosphere differs significantly from beneath a glacier. As a glacier melts, changes to the biogeochemical processes generate environmental gradients. This study analyzed chemical weathering signals at different distances from a glacial front by comparing the elemental composition of leachate derived from sediments in southeastern Greenland. Samples from proglacial, nonglacial, and moraine locations were weathered in a laboratory setting, and ion chromatography was used to determine the elemental composition of the products. Divergent trends in leachate composition were observed as distance …


Study Of Trace Elements In Southern Nevada Spring Waters And Lakes, Hyejeong Lee May 2023

Study Of Trace Elements In Southern Nevada Spring Waters And Lakes, Hyejeong Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Comprehending the natural water resource is imperative for the entire state of Nevada and of particular significance for Southern Nevada, where rapid population growth and climate change are placing significant strain on supplies. This research underscores the significance of water chemistry in identifying potential water source areas through trace elements. For the first time, the study proposed measuring the compositions of the entire suite of metal elements, ranging from Li to U, in over 40 springs in the Moapa Valley and its upper gradient valleys, utilizing the iCAP Qc ICP-MS (Inductively Coupled Plasma Mass Spectrometer) at UNLV. The research evaluated …


Geochemical Analysis And Numerical Modeling Of Central And East Tennessee Mississippi Valley-Type Ore Districts: Constraints On Ore Genesis, Jackson Price Copeland May 2023

Geochemical Analysis And Numerical Modeling Of Central And East Tennessee Mississippi Valley-Type Ore Districts: Constraints On Ore Genesis, Jackson Price Copeland

Geosciences Undergraduate Honors Theses

A simple two-way stochastic mixing model is presented for analysis of the lead (Pb) isotope compositions of the North American Mississippi Valley-Type (MVT) districts of East Tennessee, Central Tennessee, and Central Kentucky. Four distinct mixing scenarios were run to critically evaluate the stochastic model and examine different hypotheses regarding the genesis of Central Tennessee and Central Kentucky MVT deposits. Additionally, Pb isotope analysis was conducted on sphalerite samples from the Central and East Tennessee MVT districts. Model and sampling results suggest that Central Tennessee and Central Kentucky ores likely formed by mixing of three fluids. In contrast to conclusions from …


Geochemical Analysis Of Recent Volcanic Ash Blanketing Barbados And Constraints On Magma Composition (V32e-0112), Nazrul I. Khandaker, Krishna Mahabir, Surendranauth Mahabir, Lloyd Kiefer, Juan C. Campo, Andrew M. Singh Oct 2022

Geochemical Analysis Of Recent Volcanic Ash Blanketing Barbados And Constraints On Magma Composition (V32e-0112), Nazrul I. Khandaker, Krishna Mahabir, Surendranauth Mahabir, Lloyd Kiefer, Juan C. Campo, Andrew M. Singh

Publications and Research

Preliminary field and geochemical investigations were conducted on ash samples from Barbados to chemically characterize and decipher magma chemistry associated with a recent volcanic event. A thick plume of volcanic ash from the La Soufriere Volcano in St Vincent, which erupted on April 9, 2021, caused lower visibility due to ash clouds which engulfed the region for some time. Three authors from the research team visited Barbados during the summer subsequent and completed a reconnaissance investigation on recent ashfall. St Vincent is a small volcanic island in the Eastern Caribbean and lies in the southern part of the Lesser Antilles …


Research Progress Of Multi-Source And Multi-Stage Genesis Of Co2-Enriched Cbm And The Enlightenments For Its Exploration And Development, Tang Shuling, Tang Dazhen, Sun Bin, Tao Shu, Zhang Taiyuan, Pu Yifan, Zhang Aobo, Zhi Yuanhao Mar 2022

Research Progress Of Multi-Source And Multi-Stage Genesis Of Co2-Enriched Cbm And The Enlightenments For Its Exploration And Development, Tang Shuling, Tang Dazhen, Sun Bin, Tao Shu, Zhang Taiyuan, Pu Yifan, Zhang Aobo, Zhi Yuanhao

Coal Geology & Exploration

CO2-enriched coalbed methane(CBM) carries important geological information on CBM genesis and accumulation, and is closely related to the exploration and evaluation of CBM resources. On the basis of the systematic summary of the current research progress of CBM genesis, the current research status of the genetic mechanism of CO2-enriched CBM reservoirs was scientifically analyzed by dissecting the special geological examples of CO2-enriched CBM reservoirs in the southern Junggar Basin, and the problems in the research process of CBM genesis were comprehensively pointed out. The study shows that the generation of CBM has multiple sources …


Geochemical Characteristics Of Marine-Continental Transitional Facies Shale And Shale Gas In Linxing Area, Chen Xin, Wu Peng, Gao Jixian, Hu Weiqiang, Ding Wangui, Li Yangbing, Liu Xueqing, Ma Litao, Liu Cheng, Kong Wei, Cao Di, Chen Jianqi, Li Yong Dec 2021

Geochemical Characteristics Of Marine-Continental Transitional Facies Shale And Shale Gas In Linxing Area, Chen Xin, Wu Peng, Gao Jixian, Hu Weiqiang, Ding Wangui, Li Yangbing, Liu Xueqing, Ma Litao, Liu Cheng, Kong Wei, Cao Di, Chen Jianqi, Li Yong

Coal Geology & Exploration

In order to reveal the geochemical characteristics of shale and shale gas on the east edge of Ordos Basin, thin section identification, full rock and clay content, scanning electron microscope, organic carbon, rock pyrolysis, kerogen macerals, and kerogen carbon isotopes were tested, and the gas component and carbon isotopes composition of shale were analyzed. The results show that the mineral component of the transitional facies shale in Linxing area is mainly quartz and clay minerals, containing a small amount of calcite, plagioclase, potassium feldspar, dolomite and pyrite. Affected by the mineral genesis and deposition environment, different mineral components and organic …


Geochemical Characteristics And Genesis Of Coalbed Methane In Baode Area, Li Yangbing, Zeng Lei, Hu Weiqiang, Chen Xin, Ma Litao, Liu Cheng, Huang Ying, Qiao Fang Apr 2021

Geochemical Characteristics And Genesis Of Coalbed Methane In Baode Area, Li Yangbing, Zeng Lei, Hu Weiqiang, Chen Xin, Ma Litao, Liu Cheng, Huang Ying, Qiao Fang

Coal Geology & Exploration

In order to find out the geochemical characteristics and origins of coalbed methane(CBM)in Baode area, coal, CBM and water samples were collected, gas component analysis, quality detection of CBM well-produced water and stable isotope analysis were carried out. The results show that CH4 is the main hydrocarbon gas in CBM composition and its volume fraction ranges from 88.60% to 97.59%; a small amount of ethane is contained, and the volume fraction is only 0.01%-0.14%. The drying coefficient is greater than 0.99, the CBM belongs to the extremely dry CBM. The non-hydrocarbon components mainly contain CO2 and N2 …


Internal Loading Of Nitrogen (N) And Phosphorus (P), Reduced N Forms, And Periodic Mixing Support Cyanobacterial Harmful Algal Blooms (Habs) In Shallow, Eutrophic Honeoye Lake (New York, Usa), Justin Adam Myers Jan 2021

Internal Loading Of Nitrogen (N) And Phosphorus (P), Reduced N Forms, And Periodic Mixing Support Cyanobacterial Harmful Algal Blooms (Habs) In Shallow, Eutrophic Honeoye Lake (New York, Usa), Justin Adam Myers

Browse all Theses and Dissertations

Cyanobacteria are important primary producers, but large cyanobacterial harmful algal blooms (HABs) have many negative ecological and health impacts and are becoming increasingly common. Honeoye Lake (New York, USA) is a shallow, eutrophic lake characterized by increasingly frequent HABs. Nitrogen (N) and phosphorus (P) loads often drive HABs in lakes, and sediment processes can contribute to N removal (e.g., denitrification) or loading (e.g., N fixation, remineralization). Sediment cores and lake water were collected during May–October (2016–2018) at two sites and incubated with no amendments (controls) or 15N stable isotopes to measure sediment nutrient fluxes and N cycling dynamics in Honeoye …


Variations In Produced Water Chemistry And Relation To Regional Geology And Production In The Marcellus Shale, Northcentral West Virginia, Jonathan M. Brady Jan 2021

Variations In Produced Water Chemistry And Relation To Regional Geology And Production In The Marcellus Shale, Northcentral West Virginia, Jonathan M. Brady

Graduate Theses, Dissertations, and Problem Reports

An investigation of 74 Marcellus Shale wells across northcentral West Virginia indicates changes in produced water chemistry and quantity can be related to geologic conditions based on well logs and core data. These changes are determined by reviewing multiple produced water analyses for individual wells for periods up to ten years. Results show variations among the areas in this study. From west to east across central Harrison County to central Taylor County, then north into Monongalia County, gamma-ray logs show increasing intensity, especially in the middle and lower Marcellus. XRD mineralogy from core data shows increasing clay content from west …


Application Of High-Precision 3d Seismic Exploration Technology In Huainan Mining Area, Liu Jun, Zhao Wei, Han Biwu Dec 2020

Application Of High-Precision 3d Seismic Exploration Technology In Huainan Mining Area, Liu Jun, Zhao Wei, Han Biwu

Coal Geology & Exploration

In order to deeply analyze the indication of oil shale development characteristics on paleoenvironments and provide theoretical guidance for oil shale resource evaluation, the organic geochemistry and elemental geochemistry characteristics of the Neogene Zhangcun Formation oil shale in the central part of the Qinshui basin were analyzed by Rock-Eval and TOC and the paleoclimate and paleogeographic environments of the depositional period were discussed as well. The results show that the oil shale of Zhangcun Formation has the low oil content which Tar=4.15%, higher hydrocarbon potential, kerogen is of sapropel type(I1), which has relatively shallow burial depth. The element …


Evaluation And Analysis Of Paleoenvironments Of The Neogene Oil Shale Of Zhangcun Formation, Qinshui Basin, Liu Yanhai, Li Kunjie, Liu Dongna, Xue Shubin, Liu Yangfe, Chu Yonghui Oct 2020

Evaluation And Analysis Of Paleoenvironments Of The Neogene Oil Shale Of Zhangcun Formation, Qinshui Basin, Liu Yanhai, Li Kunjie, Liu Dongna, Xue Shubin, Liu Yangfe, Chu Yonghui

Coal Geology & Exploration

In order to deeply analyze the indication of oil shale development characteristics on paleoenvironments and provide theoretical guidance for oil shale resource evaluation, the organic geochemistry and elemental geochemistry characteristics of the Neogene Zhangcun Formation oil shale in the central part of the Qinshui basin were analyzed by Rock-Eval and TOC and the paleoclimate and paleogeographic environments of the depositional period were discussed as well. The results show that the oil shale of Zhangcun Formation has the low oil content which Tar=4.15%, higher hydrocarbon potential, kerogen is of sapropel type(I1), which has relatively shallow burial depth. The element …


Geochemical Characterization Of Base Metals In Stream Water And Sediments In The Caddo Lake Watershed, Cass, Harrison, And Marion Counties, Texas, Melinda S. Faulkner, Melanie L. Ertons, Joseph D. Watkins Sep 2020

Geochemical Characterization Of Base Metals In Stream Water And Sediments In The Caddo Lake Watershed, Cass, Harrison, And Marion Counties, Texas, Melinda S. Faulkner, Melanie L. Ertons, Joseph D. Watkins

Faculty Publications

The Caddo Lake watershed is located in northeastern Texas and encompasses much of Cass, Harrison, and Marion counties. The watershed is drained by major streams and tributaries flowing in an easterly direction over Eocene-aged rocks and sediments of the Wilcox and Claiborne groups, and empty into the western arm of Caddo Lake. Since 1995, Caddo Lake and some of its tributaries have been included on the State of Texas Clean Water Act 303(d) list by the Texas Commission on Environmental Quality (TCEQ) for impairment due to mercury content in edible tissue, depressed dissolved oxygen, base metal concentrations, and low pH …


Geochemical Characteristics Of Elements In The Paleogene Yunlong Formation And The Restoration Of Paleoenvironment In Lanping Basin, Liu Xiaokang, Zhang Zhibo, Zhu Zhijun, Wu Chuanfu, Wei Xingxing, Liu Haiyan, Jin Tengrui, Baima Quzong Aug 2020

Geochemical Characteristics Of Elements In The Paleogene Yunlong Formation And The Restoration Of Paleoenvironment In Lanping Basin, Liu Xiaokang, Zhang Zhibo, Zhu Zhijun, Wu Chuanfu, Wei Xingxing, Liu Haiyan, Jin Tengrui, Baima Quzong

Coal Geology & Exploration

In order to restore the sedimentary environment of the Paleogene Yunlong Formation in the Lanping basin, inductively coupled plasma mass spectrometry(ICP-MS) was used to analyze trace elements in 13 samples of gypsum, limestone, gypsum mud, mudstone and sandstone from the Paleogene Yunlong Formation in Lanping Basin. The sedimentary environments and paleoclimate are estimated based on the spider diagram of trace elements in each lithology and the characteristics of the ratio of Cu/Zn, Sr/Cu and Sr/Ba and the content of Sr. The results show that:gypsum, limestone, gypsum mud, mudstone and sandstone are all rich in Rb, Pb, Zr; gypsum and gypsum …


Paleoenvironment Reconstruction Of The Eocene Southeastern Tethys Using Geochemistry Of Sedimentary Rocks, Liliana CalderóN Convers Aug 2020

Paleoenvironment Reconstruction Of The Eocene Southeastern Tethys Using Geochemistry Of Sedimentary Rocks, Liliana CalderóN Convers

Theses, Dissertations and Culminating Projects

The Early Eocene hyperthermals are a series of transient global warming events that occurred between 54.09 and 52.63 Ma, and are considered as ancient analogues for future climate change. These hyperthermal events are well studied in the deep sea sites, but have not been investigated in the eastern Tethys Ocean. Here, we report new major and trace element geochemistry and stable carbon isotope data of the Early Eocene strata deposited in a shallow marine foreland basin prior to the main stage of India-Asian continent collision at Qumiba section in the Tingri County, southern Tibet. These geochemical data are used to …


A Geochemical And Statistical Investigation Of The Big Four Springs Region In Southern Missouri, Jordan Jasso Vega Aug 2020

A Geochemical And Statistical Investigation Of The Big Four Springs Region In Southern Missouri, Jordan Jasso Vega

MSU Graduate Theses

The Big Four Springs region hosts four major first-order magnitude springs in southern Missouri and northern Arkansas. These springs are Big Spring (Carter County, MO), Greer Spring (Oregon County, MO), Mammoth Spring (Fulton County, AR), and Hodgson Mill Spring (Ozark County, MO). Based on historic dye traces and hydrogeological investigations, these springs drain an area of approximately 1500 square miles and collectively discharge an average of 780 million gallons of water per day. The rocks from youngest to oldest that are found in Big Four Springs region are the Cotter and Jefferson City Dolomite (Ordovician), Roubidoux Formation (Ordovician), Gasconade Dolomite …


High-Resolution Timeseries Analysis Of Dynamic Geochemistry: A 27-Well Survey Of Contaminated Groundwater Downstream Of The Former S-3 Ponds, Oak Ridge, Tennessee, Emma Dixon Aug 2020

High-Resolution Timeseries Analysis Of Dynamic Geochemistry: A 27-Well Survey Of Contaminated Groundwater Downstream Of The Former S-3 Ponds, Oak Ridge, Tennessee, Emma Dixon

Masters Theses

Spatiotemporal variability of geochemistry of contaminated groundwater has large implications on overall water quality and ability to respond to remedial applications. Gaining knowledge of how geochemistry changes over time in an area can help establish response trends to changing external conditions like weather and level of contamination. In this study, a spatiotemporal survey was performed on 27 wells at the Y-12 Complex in Oak Ridge, Tennessee. This was completed to measure diurnal fluxes in geochemistry from seasonal changes and extreme weather conditions in three areas of historically different contamination levels from a single point contamination source. Measurements were gathered over …


Chemostratigraphy Of Carbonate Gravity Flows Of The Wolfcamp Formation In Crockett County, Midland Basin, Texas, Alex Blizzard, Julie Bloxson Jun 2020

Chemostratigraphy Of Carbonate Gravity Flows Of The Wolfcamp Formation In Crockett County, Midland Basin, Texas, Alex Blizzard, Julie Bloxson

Electronic Theses and Dissertations

Sediment gravity flows into deep-water environments are important stratigraphic traps in lithologically diverse reservoirs generating multiple plays for hydrocarbon exploration. These highly heterogeneous deposits can be studied by utilizing chemostratigraphy and higher-order sequence stratigraphy; being an accurate method for reservoir characterization. Studying these gravity flows along a carbonate platform’s slope can further expand an understanding of the stratigraphy that is filling adjacent basins. The application of elemental analyses can support in identifying mineralogy that impact reservoir quality, especially when conventional testing cannot be applied.

This study utilizes five cores containing the Wolfcamp Formation from the southeastern slope of the Central …


Investigating The Influence Of Environmental Factors On The Incidence Of Renal Disease With Compositional Data Analysis Using Balances, Jennifer M. Mckinley, Ute Mueller, Peter M. Atkinson, Ulrich Ofterdinger, Chloe Jackson, Siobhan F. Cox, Rory Doherty, Damian Fogarty, J. J. Egozcue, V. Pawlowsky-Glahn Jun 2020

Investigating The Influence Of Environmental Factors On The Incidence Of Renal Disease With Compositional Data Analysis Using Balances, Jennifer M. Mckinley, Ute Mueller, Peter M. Atkinson, Ulrich Ofterdinger, Chloe Jackson, Siobhan F. Cox, Rory Doherty, Damian Fogarty, J. J. Egozcue, V. Pawlowsky-Glahn

Research outputs 2014 to 2021

This research uses an urban soil geochemistry database of elemental concentration to examine the potential relationship between Standardised Incidence Rates (SIRs) of Chronic Kidney Disease (CKD) of uncertain aetiology (CKDu), and cumulative low level geogenic and diffuse anthropogenic contamination of soils with PTEs. A compositional data analysis approach was applied to determine the elemental balance(s) of the geochemical data showing the greatest association with CKDu. The research concludes that both anthropogenic and geogenic factors may be contributing influences to explain high incidences of CKDu, up to 12 times greater in some Super Output Areas (SOAs) than would be expected for …


Lithological And Geochemical Responses To Abrupt Global And Regional Paleoenvironmental Changes During The Aptian In A Hemipelagic Setting Of The Eastern Iberian Peninsula: A Multi-Proxy Approach, Jander Socorro Mar 2020

Lithological And Geochemical Responses To Abrupt Global And Regional Paleoenvironmental Changes During The Aptian In A Hemipelagic Setting Of The Eastern Iberian Peninsula: A Multi-Proxy Approach, Jander Socorro

FIU Electronic Theses and Dissertations

Intense episodes of environmental perturbations and regionally to globally distributed, oxygen-deprived marine facies characterize the Cretaceous sedimentary record. The Organyà Basin in the Spanish Pyrenees chronicles this period in expanded stratigraphic sequences that enabled high-resolution sampling and detailed analysis of disturbances poorly recorded in more lithologically condensed sections. Here, I present an integrated multi-proxy study aimed at understanding the Basin’s response to changing paleoenvironmental conditions during the early Aptian stage of the Cretaceous.

Results from the El Pui section indicate that large-scale (> 1‰), negative carbon isotope excursions (CIEs) that show no corresponding shifts in local sources of organic matter …


Development Of A Synthesis Method For O2-Releasing Compound For Microbiological Experiments, Danae Greco Jan 2020

Development Of A Synthesis Method For O2-Releasing Compound For Microbiological Experiments, Danae Greco

Williams Honors College, Honors Research Projects

Many celestial bodies within our solar system may have habitable environments due to the presence of liquid water. Europa, one of Jupiter’s moons, may be habitable because of its liquid ocean and other potentially biologically favorable conditions. The ocean on Europa is hypothesized to contain large amounts of oxidants and low pH due to the radiolytically processed icy ocean shell. This suspected environment on Europa is similar to the composition of acid mine drainage on Earth, which can house microbial communities in environments of extreme acidity. Similar chemical reactions in Europa’s ocean may occur to produce the appropriate reduction-oxidation gradients …


Pedogenic Processes In A Posidonia Oceanica Mat, Nerea Pineiro-Juncal, Carmen Leiva-Duenas, Oscar Serrano, Miguel Angel Mateo, Antonio Martinez-Cortizas Jan 2020

Pedogenic Processes In A Posidonia Oceanica Mat, Nerea Pineiro-Juncal, Carmen Leiva-Duenas, Oscar Serrano, Miguel Angel Mateo, Antonio Martinez-Cortizas

Research outputs 2014 to 2021

Scientists studying seagrasses typically refer to their substratum as sediment, but recently researchers have begun to refer to it as a soil. However, the logistics of sampling underwater substrata and the fragility of these ecosystems challenge their study using pedological methods. Previous studies have reported geochemical processes within the rhizosphere that are compatible with pedogenesis. Seagrass substratum accumulated over the Recent Holocene and can reach several meters in thickness, but studies about deeper layers are scarce. This study is a first attempt to find sound evidence of vertical structuring in Posidonia oceanica deposits to serve as a basis for more …


Natural Salinization Of The Jemez River, New Mexico: An Insight From Trace Element Geochemistry, Jon K. Golla Jul 2019

Natural Salinization Of The Jemez River, New Mexico: An Insight From Trace Element Geochemistry, Jon K. Golla

Earth and Planetary Sciences ETDs

The Jemez River, a tributary of the Rio Grande in north-central New Mexico, receives thermal water input from the geofluids of the Valles Caldera, an active, high-temperature, liquid-dominated geothermal system. We focus on a ∼50-km portion of the northern Jemez River. This research extends previous decadal work (Crossey et al., in prep., 2013) on major chemistry in the river by characterizing the response of 16 trace elements to geochemical contributions from geothermal waters (McCauley, Spence, Soda Dam, and Jemez Springs springs and San Ysidro mineral waters), an area with copious hydrothermal degassing (Hummingbird), and two major tributaries (Rio San Antonio …


Characterizing The Waters Of 6 Rivers In Upstate New York With A Focus On Physical Hydrology And Controls On Water Quality, Connor Horan Jun 2019

Characterizing The Waters Of 6 Rivers In Upstate New York With A Focus On Physical Hydrology And Controls On Water Quality, Connor Horan

Honors Theses

Rivers are key passageways connecting inland waters to the world’s oceans. They are responsible for the mobilization and transport of nutrients, sediments, and weathered materials. Rivers have been influential in the development of human civilization and are hubs for people and businesses to populate. As our population puts a heavier burden on these waterways, there is a need to better understand the controls on their water quality.

The overarching goal of this research is to improve our understanding of the hydrology and water resources of the Upper Hudson and Mohawk watersheds. This is critical to our understanding of the ecological …


Mercury In Big Cypress Bayou And Caddo Lake Watersheds In Marion And Harrison Counties Texas, Joseph Watkins Dec 2018

Mercury In Big Cypress Bayou And Caddo Lake Watersheds In Marion And Harrison Counties Texas, Joseph Watkins

Electronic Theses and Dissertations

Caddo Lake has been included on the Texas Commission on Environmental Quality 303(d) list for impairment due to mercury (Hg) content since 1996. One of the primary tributaries, Big Cypress Bayou, flows across Eocene-aged rocks and sediments associated with the Wilcox Group; the Wilcox is of interest because it contains lignite coal, which has a direct link to mercury. Previous research has focused on dry deposition from fossil fuel combustion as the primary source of mercury but has not addressed the potential watershed contribution to mercury concentrations in Caddo Lake.

Big Cypress Bayou flows through Harrison and Marion counties in …


Source, Transport, And Age Of Sediment From Cascade Volcano Watersheds To The Nearshore: Insights For Contaminant And Ecological Studies, Renee Takesue, Kathy Conn, Margaret Dutch Apr 2018

Source, Transport, And Age Of Sediment From Cascade Volcano Watersheds To The Nearshore: Insights For Contaminant And Ecological Studies, Renee Takesue, Kathy Conn, Margaret Dutch

Salish Sea Ecosystem Conference

Inputs of sediment and sediment-bound contaminants from urbanized watersheds to the nearshore region are a growing concern as coastal populations increase around the Salish Sea and worldwide. Geochemical sourcing and aging of nearshore sediment is one potential way to: a) distinguish land-derived sediment in nearshore environments, b) gain insights about how sediment and contaminants are redistributed, and c) determine how recently they were deposited. Sediments from Cascade volcanoes have distinct geochemical compositions that allow discrimination between land-derived (volcanic) and marine (lowland) sediment. As sediment is transported by rivers to the nearshore, it adsorbs particle-reactive contaminants and short-lived radionuclides, and the …


Carbon Flux And Weathering Processes In Icelandic Glacial-Fed Rivers, Allison Quiroga Apr 2018

Carbon Flux And Weathering Processes In Icelandic Glacial-Fed Rivers, Allison Quiroga

Masters Theses & Specialist Projects

An investigation into the carbon dynamics and weathering processes occurring in Icelandic glacial-fed streams was conducted during the spring to summer seasonal transition in June of 2017. Four major outlet rives were sampled from the glaciers of Gígjökull, Steinsholtsjökull, Sólheimajökull, and Falljökull. Markarfljót, the major river that Gígjökull, Steinsholtsjökull, and many other glaciers drain into, was also sampled. Longitudinal sampling occurred at all sites to capture downstream trends in the hydrogeochemistry and carbon dynamics. Distinct differences in geochemistry between glacier surface meltwater, sub-glacial waters, pro-glacial lake water, and post-mixed downstream samples were evident in the data. Glacier surface streams were …


Geochemistry And Mineralogy Of Late Quaternary Loess In The Upper Mississippi River Valley, Usa: Provenance And Correlation With Laurentide Ice Sheet History, Daniel R. Muhs, E. Arthur Bettis Iii, Gary L. Skipp Mar 2018

Geochemistry And Mineralogy Of Late Quaternary Loess In The Upper Mississippi River Valley, Usa: Provenance And Correlation With Laurentide Ice Sheet History, Daniel R. Muhs, E. Arthur Bettis Iii, Gary L. Skipp

United States Geological Survey: Staff Publications

The midcontinent of North America contains some of the thickest and most extensive last-glacial loess deposits in the world, known as Peoria Loess. Peoria Loess of the upper Mississippi River valley region is thought to have had temporally varying glaciogenic sources resulting from inputs of sediment to the Mississippi River from different lobes of the Laurentide Ice Sheet. Here, we explore a new method of determining loess provenance using K/Rb and K/Ba values (in K-feldspars and micas) in loess from a number of different regions in North America. Results indicate that K/Rb and K/Ba values can distinguish loess originating from …