Methane derived authigenic carbonate (MDAC) precipitation occurs within marine sediments as a byproduct of the microbial anaerobic oxidation of methane (AOM). While these carbonates form in chemical and isotopic equilibrium with the fluids from which they precipitate, burial diagenesis and recrystallization can overprint these signals. Plane polarized light (PPL) and...
Quantifying the mass transport through marine sediments, and the geochemical response to such flow with numerical models has become a common and powerful approach for geochemical data interpretation. In this dissertation, I developed and applied transport-reaction models to unravel complex and interdependent reactions involving carbon, sulfur and silica transformations in...
The rare earth elements (REEs) have been established as powerful tracers for a range of physiochemical processes occurring in the natural environment. They also hold significant economic importance as many technological advancements are reliant upon the REEs for their unique magnetic, luminescent, and electrochemical characteristics. In sedimentary settings, understanding the...
Given the current state of our oceans, the Pew Oceans Commission (1993) has strongly recommended that increased efforts be made towards ocean literacy. Informal education and outreach programs like the Whale Watching Spoken Here program are important contributors to life-long learning. However, there is little research looking at how these...
The distribution of barite (BaSO₄) in marine sediments has long been studied as a proxy for paleoproductivity. While pure barite is known to be a stable mineral in oxic sediments, it is also known that variations in the Sr/Ba ratio influence its solubility and liability during early diagenesis. To extract...
Nares Strait is one of three main passages of the Canadian Archipelago that
channels freshwater from the Arctic Ocean to the North Atlantic. There are very few
observations regarding the role of this region on the present day Arctic freshwater budget,
and even less regarding the changes in freshwater fluxes...
Large barite (BaSO4) structures mark cold seeps in the southern San Clemente Basin. Barium flux to San Clemente sediments is two to three times greater than fluxes measured in surrounding California Borderland basins. Analyses of sediment trap material, water column samples, sediments and pore water indicate that expected bariumbearing mineral...
The number of Latinx students enrolling in higher education has grown significantly over the past two decades (Jabbar et al., 2019). This study explores a portion of that population by focusing on the experiences of Latinx transfer students at a 4-year institution within the Pacific Northwest of the United States....
This report describes the results of semiquantitative analysis of clay mineral composition by X-ray diffraction. The samples consist of hemipelagic mud and mudstone cored from Hydrate Ridge during Leg 204 of the Ocean Drilling Program. We analyzed oriented aggregates of the clay-sized fractions (<2 μm) to estimate relative percentages of...
The Cooperative Institute for Oceanographic Satellite Studies
(CIOSS) partners with The Science and Math Investigative Learning
Experiences (SMILE) Program to bring ocean sciences and satellite
oceanography to high school students and teachers around the
state of Oregon. This study was conducted as a formative program
assessment during the third year...
Abstract
Current methods employed in the textile industry are unsustainable because they use an abundance of water in the dying process, and discharge the waste into the environment, causing adverse health effect on aquatic life and local communities. The technology that is in place to remove dye from textile effluents...
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Dye Adsorbed (Dist. Water) Dye Adsorbed (Salt Water)
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This study reports on the creation and testing of a model concept-mapping process that will aid the development and documentation of ocean science educational content of The Science and Math Investigative Learning Experiences (SMILE) Program, a pre-college science and math enrichment program based at Oregon State University. The project uses...
Isotopic characterization of carbon in the dissolved inorganic carbon (DIC) pool is fundamental for a wide array of scientific studies directly related to gas hydrate research. In order to generate integrated and internally consistent data of δ¹³C of DIC in pore waters from Hydrate Ridge, we used the modern continuous...
The investigation described in this project will test the hypothesis that fluxes of carbon, barium, manganese, iron and uranium associated with fluid seepage at the San Clemente fracture zone significantly affect the geochemical budgets for these elements, and ultimately result in anomalously high benthic fluxes throughout the San Clemente basin.
Aquatic and riparian systems in the western United States have been highly modified by anthropogenic impacts since Euro-American settlement. Ecological restoration is a practice that has been widely conducted around the world to mitigate the degradation of these systems. The majority of stream restoration efforts have focused on improving in-stream...
Many trace elements (e.g., Zn, Cd, Mo) are essential phytoplankton micronutrients, making them crucial to the marine ecosystem and ultimately the carbon cycle. Because of this association trace metals are also utilized in paleoceanographic studies (e.g., Mo, Cd). However, not much is known about what controls the cycling of these...
To assist with risk-assessment with deepwater and ultra-deepwater prospects for offshore energy extraction as well as provide a useful tool for oil spill response, a spatially-explicit model was developed for comprehensive simulations of a blowout event from the wellhead to final fate and degradation. The Blowout and Spill Occurrence Model...
Brooks Island, located in central San Francisco Bay, California, currently supports the largest breeding colony of Caspian terns (Hydroprogne caspia) in the Bay Area, and is one of several proposed relocation sites for some Caspian terns from the world's largest colony in the Columbia River estuary of Oregon. Juvenile salmonids...
This thesis develops a manual for interpreters at six National Park Service areas established to preserve and interpret fossils of the Cenozoic Era: Fossil Butte National Monument (Wyoming), John Day Fossil Beds National Monument (Oregon), Badlands National Park (South Dakota), Florissant Fossil Beds National Monument (Colorado), Agate Fossil Beds National...
Hydroxylamine is a constituent of the nitrogen cycle which has been shown to be an intermediate in both nitrification and nitrate reduction in several in-vitro studies. However, there have been no investigations into the concentrations and distributions of hydroxylamine
in the marine environment. The purpose of this work was to...
Ocean Drilling Program (ODP) Leg 204 to Hydrate Ridge, located on the continental slope offshore Oregon (USA), was the first drilling expedition dedicated to understanding gas hydrate processes in accretionary complexes and provided a testbed for a number of different techniques for estimating the gas hydrate content of sediments. It...
Oxygen and strontium isotopic composition of sedimentary pore fluids obtained by drilling at the Chile Triple Junction have been used to obtain information on the diagenesis and transport mechanisms of fluids. Samples were collected from three sites located on an east-west transect of the pre-collision zone (Sites 859, 860, and...
The isotopic compositions of interstitial waters collected from Hydrate
Ridge during Ocean Drilling Program Leg 204 were measured to
evaluate the fluid evolution of this accretionary prism. At shallow
depths, the dissolved Cl- concentrations and δD and δ¹⁸O values of the
interstitial water reflect changes in the salinity and the...
We report on geochemical data from anoxic sequences of the Nicobar Fan, recovered during International Ocean Discovery Program (IODP) expedition 362 to the Sumatra subduction zone. Analyses include strontium and carbon isotope composition of pore fluids, elemental and isotopic composition of carbonate concretions, and whole sediment analyses.
Biogeochemical mechanisms employed by key organisms, or symbiotic associations of organisms, transform the function and structure of their environment through processes recognized as ecosystem engineering. This dissertation seeks to investigate organism-ecosystem interactions that serve globally significant ecological functions in marine systems and impact how systems respond to environmental change. Using...
While water scarcity and energy demand are continuously increasing in the world, alternative sources are needed to meet the requirement of a growing population. Microbial Fuel Cell (MFC) is a sustainable technology that converts organic matter in wastewater into electricity, thus it can be a potential alternative source for water...
Despite more than two centuries of exploration, including more than six million deep wellbores with depths exceeding 40,000 feet in some parts of the world, our ability to constrain subsurface processes and properties remains limited. Characteristics of the subsurface vary and can be analyzed on a variety of spatial scales....
Marine sediments contain an abundance of methane that is biologically produced
and plays a significant role in the global carbon cycle. Microbes responsible for the
carbon cycle in marine sediments, and the processes that they carry out, need to be
characterized in order to fully understand the role of this...
In this thesis I present the results of a comprehensive assessment of the Pacific-North American (PNA) teleconnection pattern in general circulation models (GCMs) and a regional climate model (RCM). The PNA teleconnection pattern is a quasi-stationary wave field over the North Pacific and North America that has long been recognized...
The overall purpose of this research is to assess the Oregon public's capacity to address water resources disturbances through civil society. According to scientists and resource managers, Oregon's water resources are over taxed and at risk, with future projections placing additional stress from climate change and population growth. Oregon's 2009...
With an ever-growing urban population there is a continued interest in urban agriculture as a viable option to improve access to fresh produce and enhance food security in an increasingly urbanized world. As the primary method of urban agriculture in the United States, community gardens also provide a range of...
The working hypothesis for this study is that the introduction of GIS technology into the ancient procedures of map-making has changed the map-making context sufficiently to require a revision of the way we think about, learn from, and use maps, specifically in the public involvement process in natural resource management....
The research and analysis presented in this dissertation illustrate how individuals enact lived religion as they seek to navigate social inequalities. The enactment of lived religion involves directing attention towards orientations. I use the term orientations in the sense articulated by Ahmed (2004), to allude to how bodies are situated...
We present a kinetic model based upon pore water data collected from eight sites drilled
during the second Ulleung Basin gas hydrate drilling expedition (UBGH2) in 2010.
Three sites were drilled at locations where acoustic chimneys were identified in seismic
data, and the rest were drilled on non-chimney (i.e. background)...
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, with a kinetic modeling approach 2
3
Wei-Li Hong
1
, MartaE. Torres
1
, Ji-Hoon Kim
2
, Jiyoung
Sedimentary pore fluids from the Chile Triple Junction were sampled in situ, and analyzed for their noble gas composition. ³He/⁴He and ⁴He/Ne ratios were used to evaluate the fraction of helium in the samples that originated from mantle and radiogenic sources. The results show no primordial helium in samples recovered...
Methane fluxes into the oceans are largely dependent on the methane phase as it migrates upward through the sediments. Here we document decoupled methane transport by gaseous and aqueous phases in Storfjordrenna (offshore Svalbard) and propose a three-stage evolution model for active seepage in the region where gas hydrates are...
Recent studies have suggested that the marine contribution of methane from shallow regions and melting marine-terminating glaciers may have been underestimated. Here we report on methane sources and potential sinks associated with methane seeps in Cumberland Bay, South Georgia's largest fjord system. The average organic carbon content in the upper...
Drilling in the Cascadia accretionary complex enable us to evaluate the contribution of dehydration reactions and gas hydrate dissociation to pore water freshening. The observed freshening with depth and distance from the prism toe is consistent with enhanced conversion of smectite to illite, driven by increase in temperature and age...
The significance of the various carbon cycling pathways in driving the sharp sulfate methane transition (SMTZ) observed at many locations on continental margins is still a topic of debate. Unraveling these processes is important to our understanding of the carbon cycle in general and to evaluate whether the location of...
We present a kinetic model based upon pore water data collected from eight sites drilled
during the second Ulleung Basin gas hydrate drilling expedition (UBGH2) in 2010.
Three sites were drilled at locations where acoustic chimneys were identified in seismic
data, and the rest were drilled on non-chimney (i.e. background)...
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RUNTIME
time_units years
timestep_max 500.0
timestep_init 1.E-12
time_tolerance
We present a kinetic model based upon pore water data collected from eight sites drilled
during the second Ulleung Basin gas hydrate drilling expedition (UBGH2) in 2010.
Three sites were drilled at locations where acoustic chimneys were identified in seismic
data, and the rest were drilled on non-chimney (i.e. background)...
We present a kinetic model based upon pore water data collected from eight sites drilled during the second Ulleung Basin gas hydrate drilling expedition (UBGH2) in 2010. Three sites were drilled at locations where acoustic chimneys were identified in seismic data, and the rest were drilled on non-chimney (i.e. background)...
Marine sediments are vast sources and reservoirs of methane, a potent greenhouse gas. Most of this methane is anaerobically oxidized by archaea before it can reach the overlying ocean, though the efficiency of this process often depends on methane fluxes and mechanisms of fluid transport. Anaerobic methanotrophic archaea, or ANME,...
Hydrate Ridge is an accretionary thrust ridge located on the lower slope of the central Cascadia convergent margin. Structural mapping based on two-dimensional and three-dimensional multichannel seismic reflection profiles and gridded bathymetry coupled with deep-towed sidescan sonar data and Ocean Drilling Program (ODP) biostratigraphy suggests that seafloor fluid venting patterns...
Total organic carbon (TOC) content of marine sediments represents residual carbon, originally derived from terrestrial and marine sources, which has survived seafloor and shallow subseafloor diagenesis. Ultimately, its preservation below the sulfate reduction zone in marine sediments drives methanogenesis. Within the gas hydrate stability zone (GHSZ), methane production along continental...
Sediments at the southern summit of Hydrate Ridge display two distinct modes of gas hydrate occurrence. The dominant mode is associated with active venting of gas exsolved from the accretionary prism and leads to high concentrations (15%–40% of pore space) of gas hydrate in seafloor or near-surface sediments at and...
Sporosarcina pasteurii is known to produce calcite or biocement in the presence of urea and Ca²⁺. Herein, we report the use of novel ultramicrosensors such as pH, Ca²⁺, and redox sensors, along with a scanning electrochemical microscope (SECM), to monitor a real-time, bacteria-mediated urea hydrolysis process and subsequent changes in...
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, Yvan Allau2, Circe
Verba3, Frederick Colwell2, MartaE. Torres2, Dipankar Koley1,*
1 Department of
The isotopic composition of the dissolved inorganic carbon (DIC) collected at sites of active methane discharge on Hydrate Ridge, Oregon, reveals anaerobic methane oxidation mediated by bacteria, with δ13CDIC reaching values as low as –48‰ in the upper 4 cm of the sediment. In spite of the high sulfide levels...
Analytical challenges in obtaining high quality measurements of rare earth elements (REEs) from small pore fluid volumes have limited the application of REEs as deep fluid geochemical tracers. Using a recently developed analytical technique, we analyzed REEs from pore fluids collected from Sites U1325 and U1329, drilled on the northern...
Geophysical and biogeochemical processes associated with fluid venting from active and passive continental margins will receive significant scientific and economic attention
into the next century and are of major societal relevance. An important unknown among these interrelated processes is the role played by methane gas hydrates, at and below the...