Geology Commons^™

Carbon Storage Via Mineral Bonding In Subsoils A Review Of Soil Processes, Kiele Goins

Theses and Dissertations

Soil is an important but often poorly understood portion of the carbon cycle. Soil can store more carbon than twice today’s atmosphere, but the factors that control carbon storage are often unclear. Carbon enters the soil through input of organic matter, erosion, and aerosol deposition and is lost mostly via microbial decomposition. Carbon loss in soil is impacted by the chemical composition of organic compounds, environmental factors, and human activities. Furthermore, as climate changes soil, carbon storage may be vulnerable. Although carbon can be stored throughout soil, carbon storage varies with depth. In topsoil, carbon is stored for short periods …

Groundwater Discharge From Passive Continental Margins: Rethinking Marine Chemical Budgets, Andrew William Osborne

Theses and Dissertations

Geothermal convection and sediment compaction drive large-scale flow in continental shelves. We suggest that this flow is an overlooked control on the major ion chemistry of the ocean. Conventional ocean chemical budgets are constructed using river discharge, axial mid-ocean ridge (MOR) convection and CaCO3 production, but these budgets are still poorly quantified. We synthesized data from 17 passive continental margin basins to calculate a range of estimated groundwater and chemical fluxes from continental shelves, considering five major ions (Ca2+, Na+, K+, Mg2+, and Cl-). When extrapolated globally, volumetric groundwater flux estimates were comparable to those for MOR axial circulation, and …

Modeling The Lafourche Delta Network In The Mississippi Delta Complex, Byong-Suk Chun

Graduate Theses and Dissertations

The distributary channel network morphology on deltas is important for the delta evolution study because channels are the primary conduit for carrying and distributing water, sediment, and nutrients to the coast. Numerical models of river deltas and their channels have improved remarkably over the past two decades. However, the long-term (millennial scale) simulation of real delta systems remains rare. Here, we attempt to reconstruct the Lafourche Delta channel network, active 1600-600 years before present, with a simple numerical model (Moving Boundary Model for Distributary Network, MB_DCN). The model was run for 9 possible paleo basin boundaries and 6 water discharge …

Slip And Strain Accumulation Along The Sadie Creek Fault, Olympic Peninsula, Washington, W. Cody Duckworth, Colin B. Amos, Elizabeth R. Schermer, John P. Loveless, Tammy M. Rittenour

Geosciences: Faculty Publications

Upper-plate faulting in the Olympic Peninsula of Washington State results from relative motion of crustal blocks within the Cascadia forearc and earthquake cycle processes along the Cascadia subduction zone. We reconstruct fault slip rates since ∼14 ka on the Sadie Creek fault (SCF), north of the Olympic Mountains, using airborne lidar and field mapping of surficial deposits and landforms and optically stimulated luminescence and radiocarbon dating. The SCF is a ≥14 km-long northwest-striking, subvertical, dextral strike-slip fault with a subordinate dip-slip component. Laterally, offset debris flow channels cut into Late-Pleistocene and younger surfaces show dextral slip of 4.0–24.5 m and …

Geological And Geochemical Analysis Of Phosphorus Bearing Minerals And Natural Glasses On Earth And In Meteorites: Implications Of The Origin Of Life, Tian Feng

USF Tampa Graduate Theses and Dissertations

Phosphorus is a key element in biogenic molecules and the mineral schreibersite is a major reactive phosphorus source for organic compounds on the prebiotic Earth. In this dissertation, a suite of reactions of phosphorus species, which originate from schreibersite minerals on chondrite meteorites and on the early Earth, have been studied to determine the intermediate geochemical pathways between phosphides and common minerals on meteorites and on the early earth.

I first investigated a unique blue fulgurite that was studied to clarify if this blue color was caused by rich phosphorus content, as has been reported for impact glasses that also …

A Global Dataset Of Atmospheric 7be And 210pb Measurements: Annual Air Concentration And Depositional Flux, Fule Zhang, Jinlong Wang, Mark Baskaran, Qiangqiang Zhong, Yali Wang, Jussi Paatero, Jinzhou Du

Environmental Science and Geology Faculty Research Publications

7Be and 210Pb air concentration and depositional flux data provide key information on the origins and movements of air masses, as well as atmospheric deposition processes and residence time of aerosols. After their deposition onto the Earth's surface, they are utilized for tracing soil redistribution processes on land, particle dynamics in aquatic systems, and mixing processes in open ocean. Here we present a global dataset of air concentration and depositional flux measurements of atmospheric 7Be and 210Pb made by a large number of global research communities. Data were collected from published papers between 1955 and early 2020. It includes the …

239-30k, Scott Brande

RockDoc - 3D Rock Models

Model created by Dr. Scott Brande

Rock formed May 2021 during eruption of mantle-sourced magma from Fagradalsfjall volcano in the valley of Geldingadalir, Iceland. Many thanks to Ben Smith and Danny Smith for collecting the sample under the fall of hot debris. Sample size about 6 cm.

An Actionable Anti-Racism Plan For Geoscience Organizations, Hendratta N. Ali Ph.D., Sarah L. Sheffield, Jennifer E. Bauer, Rocío P. Caballero-Gill, Nicole M. Gasparini, Julie Libarkin, Kalynda K. Gonzales, Jane Willenbring, Erika Amir-Lin, Julia Cisneros, Dipa Desai, Maitri Erwin, Elisabeth Gallant, Kiara Jeannelle Gomez, Benjamin A. Keisling, Robert Mahon, Erika Marín-Spiotta, Leiaka Welcome, Blair Schneider

Geosciences Faculty Publications

Geoscience organizations shape the discipline. They influence attitudes and expectations, set standards, and provide benefits to their members. Today, racism and discrimination limit the participation of, and promote hostility towards, members of minoritized groups within these critical geoscience spaces. This is particularly harmful for Black, Indigenous, and other people of color in geoscience and is further exacerbated along other axes of marginalization, including disability status and gender identity. Here we present a twenty-point anti-racism plan that organizations can implement to build an inclusive, equitable and accessible geoscience community. Enacting it will combat racism, discrimination, and the harassment of all members.

Field And Remote Sensing Analysis Of The 2015 Pyroclastic Density Currents At Colima (Mexico) And Calbuco (Chile) Volcanoes: Implications For Hazard Assessment And Crisis Management, Elodie Macorps

USF Tampa Graduate Theses and Dissertations

Although one of the most spectacular phenomena of active volcanoes, Pyroclastic density currents, or PDCs, are considered the most dangerous volcanic hazards. PDCs are avalanches of hot volcanic gases, ash, and larger volcanic fragments that travel at incredible speed down the flank of a volcano. High dynamic pressures, high temperatures, and high velocities are the primary dangers associated with PDCs and lead to near-complete destruction and death.

I use a multi-disciplinary approach to study the deposits left behind by PDCs, in order to understand their dynamics, their interactions with the receiving landscape, and their final distribution, starting on the ground …

Revised Fractional Abundances And Warm-Season Temperatures Substantially Improve Brgdgt Calibrations In Lake Sediments, Jonathan H. Raberg, David J. Harning, Sarah E. Crump, Gregory De Wet, Aria Blumm, Sebastian Kopf, Áslaug Geirsdóttir, Gifford H. Miller, Julio Sepúlveda

Geosciences: Faculty Publications

Distributions of branched glycerol dialkyl glycerol tetraethers (brGDGTs) are frequently employed for reconstructing terrestrial paleotemperatures from lake sediment archives. Although brGDGTs are globally ubiquitous, the microbial producers of these membrane lipids remain unknown, precluding a full understanding of the ways in which environmental parameters control their production and distribution. Here, we advance this understanding in three ways. First, we present 43 new high-latitude lake sites characterized by low mean annual air temperatures (MATs) and high seasonality, filling an important gap in the global dataset. Second, we introduce a new approach for analyzing brGDGT data in which compound fractional abundances (FAs) …

A Study Of Stable Isotopes In Snow On Mt. Hood, Oregon, Maya Felix

University Honors Theses

Over the 2020-2021 Winter, event-based and end-of-season snow samples were collected on Mt. Hood near Government Camp, OR and analyzed for their stable isotopic compositions of ¹⁸O and ²H. It was found that surficial snow collected through the winter had higher variation in isotopic values than samples from a snow pit collected in spring. This suggests homogenization occurred in the snowpack over the season from snow metamorphism, sublimation, and/or melting. Homogenization of the snowpack will likely become more pronounced as temperatures increase and rain falls more often than snow due to climate change. Research that utilizes the snowpack …

Ductile And Brittle Deformation Of Slackwater Deposits In The Tucannon River Valley, Chelsi K. Howard

Geosciences Student Work

The Tucannon River valley in eastern Washington is home to a number of ductile and brittle soft-sediment deformation. This project aims to look at ductile deformation by classifying and comparing styles of clastic dikes in the field and to look at brittle deformation by analyzing small faults in localized outcrops. Clastic dikes are sedimentary intrusions into other sedimentary strata. There are three main types of clastic dikes: injection, extrusion, and sugtrusion. In addition, two subcategories of clastic dikes are described as sheeted dikes and fault injection dikes. Ductile and brittle deformation occurs in “slackwater” deposits associated with margins of glacial …

Geologic Study Of The Palisades Park, Spokane, Washington, Ethan Jeffrey Ducken, Alex Michael Navarra

Geosciences Student Work

The Palisades Park is a large City owned tract of land located on the western bluffs above Spokane. The purpose of this project was to create a geologic map and assess the features within the park for the benefit of a public conservation group, Friends of the Palisades. There are 3 main units identified by previous research in the vicinity. Volcanic rock units are part of the Columbia River Basalt Group (CRBG), which erupted primarily between 16.5 to 15.6 MA (Hammond 2013). Large sedimentary interbeds identified as Latah formation present between CRB flows (Swanson et al 1979a, 1979b). Latah formation …

Mineralogical Restrictions On Porosity In The Taylor Sand Of The Cotton Valley Group, Northern Louisiana Salt Basin, Claiborne Parish, Louisiana, Kaleb C. Mcclain

Electronic Theses and Dissertations

The Cotton Valley Group has been targeted for hydrocarbons since the 1940s. However, the reservoir was initially considered uneconomical to drill due to its low permeability and porosity. Since then, recent technological advances in hydraulic fracturing have allowed the Cotton Valley Sandstone members to become prolific, profitable plays, renewing interest in drilling and exploration across the northwest/northern Louisiana region.

In this research, mineralogical restrictions on the porosity in the Lower Taylor Sand of the Cotton Valley Group were studied from core (10,035’ft/3,059m -10,150’ft/3,094m) from Blackburn Field, northwest Claiborne Parish. Twelve samples were taken at intervals throughout the Taylor Sand, starting …

Precambrian Basement Influence On The Deposition Of The Upper Ordovician Utica Shale Play In East Central Ohio, William Kaleb Kirk

Electronic Theses and Dissertations

The Ordovician Utica shale play is a major oil and gas producing interval in the Appalachian Basin. The Utica shale play can be found as far as New York and Canada and to the south into Indiana and Kentucky. The play consists of the Trenton/Lexington limestones, Point Pleasant Formation, and Utica shale. The shallow marine fossiliferous limestones of the Trenton and shallow marine shaley limestones of the Lexington are overlain by an interbedded shale and limestone of the Point Pleasant Formation, which grade into the deeper marine interbedded shales and limey shales of the Utica. These formations are highly heterogeneous, …

Deposition And Diagenesis Of The Blossom Sand, Panola County, Texas, Hannah Chambers

Electronic Theses and Dissertations

The Late Cretaceous Blossom Sand within the Austin Group is a historic gas reservoir in the East Texas basin, located at depths of approximately 2,000 ft below the surface. Since the discovery of the Carthage Field in 1918 in the East Texas Basin, the Blossom Sand has produced approximately 26 BCF of gas with minor amounts of oil. Despite its notoriety in the Carthage Field, there is very little research that has been conducted on this unit, although it crops out in northeast Texas and is found in the subsurface of southwest Arkansas, western Louisiana, and the East Texas Basin. …

The Spatial And Temporal Evolution Of The Portland And Tualatin Forearc Basins, Oregon, Usa, Darby P. Scanlon, John Bershaw, Ray E. Wells, Ashley R. Streig

Geology Faculty Publications and Presentations

The Portland and Tualatin basins are part of the Salish-Puget-Willamette Lowland, a 900-km-long, forearc depression lying between the volcanic arc and the Coast Ranges of the Cascadia convergent margin. Such inland seaways are characteristic of warm, young slab subduction. We analyzed the basins to better understand their evolution and relation to Coast Range history and to provide an improved tectonic framework for the Portland metropolitan area. We model three key horizons in the basins: (1) the top of the Columbia River Basalt Group (CRBG), (2) the bottom of the CRBG, and (3) the top of Eocene basement. Isochore maps constrain …

Teleseismic P-Wave Attenuation Beneath The Southeastern United States, Ashutosh Shrivastava, Kelly H. Liu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Seismic attenuation is an important parameter for characterizing subsurface morphology and thermal structure. In this study, we use P-wave amplitude spectra from 588 teleseismic events recorded by 477 broadband seismic stations in the southeastern United States to examine the spatial variations of seismic attenuation in the crust and upper mantle. The resulting seismic attenuation parameter (∆t*) measurements obtained using the spectral ratio technique reveal a zone of relatively low attenuation in the Gulf of Mexico Coastal Plain and the southwestern terminus of the Piedmont province. Spatial coherency analysis of the ∆t* observations suggests that the center of the low attenuation …

Soarnet, Deep Learning Thermal Detection For Free Flight, Jake T. Tallman

Master's Theses

Thermals are regions of rising hot air formed on the ground through the warming of the surface by the sun. Thermals are commonly used by birds and glider pilots to extend flight duration, increase cross-country distance, and conserve energy. This kind of powerless flight using natural sources of lift is called soaring. Once a thermal is encountered, the pilot flies in circles to keep within the thermal, so gaining altitude before flying off to the next thermal and towards the destination. A single thermal can net a pilot thousands of feet of elevation gain, however estimating thermal locations is not …

Probabilistic Seismic Hazard Analysis For Northern Tanzania Divergence Region And The Adjoining Areas, Michael M Msabi, Richard W Ferdinand

Tanzania Journal of Science

This paper presents the seismic hazard levels for the Northern Tanzania Divergence (NTD) and adjoining areas by using area seismic source zones. The 15 source zones were considered based on the major geological and tectonic features, faulting style, and seismicity trends. For each source, earthquake recurrence parameters were computed by using the earthquake catalogue with events compiled from 1956 to 2011. The peak ground accelerations (PGA) and spectral accelerations (SA) at 0.2 and 2.0 second, respectively, were computed for a 10% probability of exceedance in 50 years at sites defined by a 0.1° x 0.1° grid. The recurrence parameters of …

Mapping Of Geological Structural Features In Lolgorien, Narok County, Kenya: Using Hillshade Analysis, Sammy O Ombiro, Akinade S Olatunji, Eliud M Mathu, Taiwo R Ajayi

Tanzania Journal of Science

Despite Lolgorien being one of the most active gold mining areas in Kenya, it is one of the most geologically understudied areas. To the best knowledge of the authors, Lolgorien geological map was last updated in the 1940s. Current technologies such as remote sensing allow new structural features such as faults to be easily identified. In this regard, this study employed remote sensed data to map structural features found in and around Lolgorien Subcounty, Narok, Kenya. This was done to identify any new structural features that might have been missed in the past. Shuttle Radar 152 Topography Mission Digital Elevation …

Hydrogeophysical Investigation For The Aquifers In Part Of Ilorin, Central Nigeria: Implication On Groundwater Prospect, Ayodele Kehinde Olawuyi

Tanzania Journal of Science

Hydrogeophysical study involving the use of Vertical Electrical Sounding (VES) was carried out in part of the basement complex rocks of Ilorin, central Nigeria, with the aim of determining its geoelectric parameters and groundwater potential. A total of thirty (30) VES were carried out using Schlumberger electrode configuration, with half electrode separation (AB/2) varying from 1m to 100m. Information on the subsurface lithologies, overburden thickness and aquiferous layers were obtained from the different VES locations in the study area. From the quantitative interpretations of the data collected, using the method of curve matching with the Orellana-Mooney master curves and 1-D …

Probabilistic Seismic Hazard Assessment And Site Analyses Of Arusha International Conference Centre (Aicc), Arusha, Tanzania, Richard W Ferdinand

Tanzania Journal of Science

This work presents the evaluation of earthquake resistance of the Arusha International Conference Centre (AICC) complex, in Tanzania. The evaluation included probabilistic seismic hazard analysis (PSHA) and site response analysis. Seismic sources considered to constitute a seismic hazard in this study were randomly occurring seismicity located within five tectonic provinces around the site. For each province the seismic hazard is based on a cursory analysis of earthquake data from compiled ESARSWG bulletins and temporary deployed networks within the North Tanzania Divergence (NTD). Bedrock response signal together with the information of material characteristics from boreholes around the AICC site were used …

Upgrading Biogas Using Eburru Zeolitic Rocks And Other Adsorbent Materials To Remove Carbon Dioxide And Hydrogen Sulphide, James K Mbugua, Joseph M Mwaniki, Damaris M Nduta, Francis B Mwaura

Tanzania Journal of Science

The trace amounts of carbon dioxide and hydrogen sulfide in raw biogas lower its calorific value,cause corrosion and make it hard to compress biogas into the cylinder. Raw biogas was obtainedfrom anaerobic digestion of cow dung and market wastes. The gas was stored in tubes or urine bagbefore upgrading. Natural zeolite rocks, maize cobs, steel wire, desulphurizer, and worn-out tyreswere used as the upgrade materials. The composition of biogas was recorded before and afterupgrading using a GP180 portable biogas analyzer from Henan, China. The measured level of rawbiogas was 0.0227% H2S, >20% CO2 and 52-56% CH4. The most efficient upgrade …

Evaluation Of Petroleum Hydrocarbons Contamination In Soils And Groundwater Using Electrical Resistivity And Hydrochemical Methods-Case Study: Ayetoro, Osogbo Southwestern Nigeria, Mutiu A Fakunle, Muhydeen A Ibraheem, Wasiu B Agbaje, Luqman A Abidoye

Tanzania Journal of Science

The presence of Petroleum Hydrocarbons (PHCs) in hand-dug wells has become a concern to the residents of Ayetoro area, Osogbo. Consequently, the detection of PHCs was evaluated using, nine Vertical Electrical Soundings (VES) and 2D electrical resistivity tomography surveys. Soil samples collected were analyzed for porosity and permeability. Hand-dug well water samples were screened for PHCs. VES revealed that second layer had high apparent resistivity of 14415.0 Ωm, indicating presence of PHCs that had penetrated to maximum depth of 19.1 m. The highest resistivity of the control points was 48.0 Ωm, indicating absence of PHCs. The 2D resistivity revealed highest …

Geological Controls On Brine Discharge In Itumbula Salt Dam Within The Rukwa Rift In Momba District, Tanzania, Mwita S Maswi, Octavian Minja, Chakutema Batwenge

Tanzania Journal of Science

The Itumbula salt dam of the Rukwa Rift Basin is a depression formed through extraction of spring-derived salt crystals. Brine yield by springs which is the primary cause of significant amounts of salt in the dam required further geological investigations to understand yield controls. In this study, detailed field geological investigations in the salt dam and its surroundings were conducted to ascertain brine discharge controls. These included documentation of lithology and surface manifestations of brine deposition. Geophysical methods (i.e. magnetic and electric surveys) for studying geologic structures associated with brine deposits, and laboratory analysis of cations and anions (e.g. chlorides, …

Mineralogical And Geochemical Characteristics Of Graphite-Bearing Rocks At Chenjere Area, South-Eastern Tanzania: Implications For The Nature And Quality Of Graphite Mineralization, Charles D Moye, Michael M Msabi

Tanzania Journal of Science

This study focused on the mineralogical and geochemical characteristics of graphite-bearing rocks at Chenjere area by conducting surface geological mapping, geochemical and petrographical analyses with the intention of characterizing the nature of graphite occurrence in these lithological units. This paper presents results of the flake size, grade and mineralization extension of graphite in the graphitic gneiss. Field observations, petrographic investigation and comparison with other studies indicate that graphite occurrence at the Chenjere area is of sedimentary origin which fall under syngenetic type. The petrographic study revealed that nature of metamorphism of rocks in the Chenjere area is of high grade …

Larvicidal Potency Of Dioscorea Sansibarensis Leaf Extract Against Vector Mosquitoes: Anopheles Gambiae S.S. And Culex Quinquefasciatus, Anitha Philbert

Tanzania Journal of Science

Mosquitoes are responsible for transmission of illnesses of public health importance including malaria, lymphatic filariasis, dengue, chikungunya, and many other diseases caused by viruses. Vector control using synthetic insecticides has been the cornerstone for management of vector-borne diseases. However, the chemical based interventions have not been sustainable due to emergency of resistance against insecticides among disease vectors. Plant based mosquitocidal products can be potential alternative tools in vector control. Therefore, the present study aimed at exploring the larvicidal properties of Dioscorea sansibarensis leaf extract against malaria and lymphatic filariasis vectors; Anopheles gambiae s.s. and Culex quinquefasciatus. The larvicidal activities of …

Integration Of Geophysics And Remote Sensing Techniques In Mapping Zones Mineralised With Disseminated Gold And Sulphide Minerals In Lolgorien, Narok County, Kenya, Sammy O Ombiro, Akinade S Olatunji, Eliud M Mathu, Taiwo R Ajayi

Tanzania Journal of Science

Even though ground geophysical surveys (especially Induced polarization and resistivity) are applied in mineral exploration, their effectiveness in identification of mineralised zones is often enhanced by integrating other mineral exploration techniques such as remote sensing and geological investigations. Integrating different techniques helps in reducing uncertainty that is often associated with mineral exploration. The methods being integrated also depend on characteristics of mineralisation and those of host rock. In this study, geophysical survey methods (induced polarization and resistivity) were integrated with remote sensing and geological methods to delineate mineralised zones in Lolgorien beyond reasonable doubt. By integrating these methods, it was …

Coupled Deep-Mantle Carbon-Water Cycle: Evidence From Lower-Mantle Diamonds, Wenzhong Wang, Oliver Tschauner, Shichun Huang, Zhongqing Wu, Yufei Meng, Hans Bechtel, Ho Kwang Mao

Geoscience Faculty Research

Diamonds form in a variety of environments between subducted crust, lithospheric and deep mantle. Recently, deep source diamonds with inclusions of the high-pressure H O-phase ice-VII were discovered. By correlating the pressures of ice-VII inclusions with those of other high-pressure inclusions, we assess quantitatively the pressures and temperatures of their entrapment. We show that the ice-VII-bearing diamonds formed at depths down to 800 ± 60 km but at temperatures 200–500 K below average mantle temperature that match the pressure-temperature conditions of decomposing dense hydrous mantle silicates. Our work presents strong evidence for coupled recycling of water and carbon in the …