The Inmaculada Mine is located in the Miocene belt of epithermal deposits that extends from southern Peru to northern Chile and Bolivia. This belt is known for its silver-rich epithermal veins that have been worked since colonial times. The Inmaculada Mine belongs to a mining district that includes, from north...
Disentangling sediment source from sediment transport is a fundamental marine geologic challenge critical to the interpretation of any sedimentary record. The Eirik Ridge, a sediment drift south of Greenland, receives terrigenous sediment primarily from subglacial erosion of south Greenland’s Precambrian bedrock and Paleogene volcanics that outcrop in east Greenland and...
With the increasing international focus on transboundary cooperation as a part of the Sustainable Development Goal (SDG) Framework, there is global recognition of transboundary water cooperation as a tool for improved governance and management of transboundary surface and groundwaters. Yet, there is not an agreed upon definition of transboundary water...
The Panamint Valley fault zone (PVFZ) is an active, dextral-oblique normal fault that partially accommodates dextral shear across the Eastern California Shear Zone (ECSZ). The fault system has a complex geometry, characterized by a relatively high-angle dextral oblique normal fault in the south and a low-angle detachment system that accommodates...
Oregon’s Coastal nearshore ecosystems are a nexus between living marine resources and coincident human recreational, industrial and socio-economic development. These nearshore regions also provide habitats vital to early life history stages of commercial non-whiting groundfish species, which supplied 21% of the Oregon fishing economy in 2018. The very shallow portions...
Globally, there are 40 million internally displaced people (IDPs) and 25.4 million refugees as of 2018. Of this global refugee population, 19.9 million are under mandate by UNHCR, the United Nations Refugee Agency, while 5.4 million Palestinian refugees are protected by United Nations Relief and Works Agency for Palestine Refugees...
Rotating disc electrodes (RDEs) exploit the induced flushing of a radially spun electrode to increase the overall rate of analyte flux to an electrode sensing surface and its resulting signal current (i). Here initial efforts to evaluate a rotating platinum (Pt) microelectrode for efficacy as a rapid in situ dissolved...
Ocean acidification (OA) is the result of increasing concentrations of anthropogenic carbon dioxide (CO₂) emissions, leading to a suite of alterations to specific parameters of ocean chemistry, which can negatively impact many marine organisms and ecosystems. Understanding how to measure and monitor the chemistry of OA will require specialized education...
Informal higher education science learning programs are increasingly being used as a tool to build scientific research capacity. However, there is low understanding of the impact that these programs on their target audiences, which is important to future capacity building efforts and program design. The purpose of this research project...
The Global Overturning Circulation (GOC) is a major component of the global climate system. Understanding its behavior is pertinent to our prediction of climate change in the future. The lack of long-term observations of GOC in the modern instrumental era necessitates studies of GOC using paleoceanographic records. Of great interest...
The Walla Walla Subbasin (WWSB) in Oregon is underlain by formations of the extensive Columbia River Basalt Group (CRBG) which have been deformed by post-Miocene folding and faulting. Extensive irrigation with groundwater from these basalt groups, as well as sedimentary aquifers and surface water diversions from the Walla Walla River,...
Today’s technology-based society makes information more accessible than ever, in turn creating a growing demand for a workforce that has the skills necessary to utilize data. Contributing to this influx of data is Oregon State University (OSU), who was selected to guide the design and construction process of three Regional...
With growing populations and consumer demand, there has been a turn to the deep sea to meet our natural resource needs. The deep sea provides a range of benefits to humans—called ecosystem services—including carbon sequestration, fisheries, waste absorption and detoxification, and nutrient cycling, all of which are vital to life...
Western Saudi Arabia hosts a number of young volcanic fields, known as “Harrats”. Harrats cover a significant proportion of western Saudi Arabia and are associated with significant volcanic hazards. However, the ultimate cause of volcanic activity remains unclear. Younger volcanism (<12 Ma) is clearly represented by the north-south-trending region known...
The complex challenges that Oregon’s commercial fishing community faces are mainly driven by four sources of change: climate change, change in management regulations, societal shifts, and market trends. Challenges include increasing competition for ocean use, management decisions that prioritize economic efficiency over community values, and an increasingly uncertain environment. The...
Cinder cones are useful geomorphic features for geological analysis because they generally have known initial states and follow a similar pattern of degradation as they are exposed to erosive processes. This is largely because cinder cones are produced by monogenetic eruptions. Characterizing large cinder cone fields in terms of age...
New ice cores retrieved from the Taylor Glacier (Antarctica) blue ice area contain ice and air spanning the Marine Isotope Stage (MIS) 5/4 transition, a period of global cooling and ice sheet expansion. Chronologies were determined for the ice and air bubbles in the new ice cores by visually matching...
The frontlines of climate change adaptation will occur in rural, impoverished regions of the world where households engage in climatically dependent livelihoods, such as peasant agriculture or pastoralism. As changing climate and changing markets affect the suite of household livelihood assets (environmental, social, and economic) which enable a household to...
By inverting EarthScope long-period magnetotelluric (MT) data from the southeastern United States (SEUS), we obtain electrical conductivity images that provides key insights into the geodynamics of this region. Significantly, we resolve a highly electrically resistive block that extends to mantle depths beneath the modern Piedmont and Coastal Plain physiographic provinces....
Mount Sinabung, Sumatra, Indonesia initiated eruptive activity in 2010 with the addition of a magmatic component in 2013, after a 3 year period of quiescence. Observations of magmatic activity began with phreatomagmatic eruption starting July 2013 closely followed by extrusion of andesitic lava in December 2013. Lava effusion has persisted...
Research across natural resource management disciplines has identified an implementation gap between researchers and managers, where institutional norms and practices limit the application and synthesis of novel data and observations in decision-making. With their increasing social media and internet presence, federal agencies have grown their communication portfolios past traditional communication...
Forests play an integral role in the global carbon cycle, regulating the atmospheric CO₂ concentration by sequestering nearly one third of anthropogenic carbon emissions and storing carbon for centuries. Forest ecosystems are integrated into the culture, ecology, and economy of western North America, supporting wildlife habitat, local economies, recreation, and...
Because of their convenience and durability, single-use plastic items have become a ubiquitous part of society since the 1930s. The overuse of these convenient and durable plastic items has created a social and environmental problem that plagues our oceans and waterways. While the issue is overwhelming and daunting, it is...
Euphausiids are recognized as essential components of marine food webs throughout the world’s oceans due to their role as prey for many species including whales, seabirds, and commercial fishes. The Kitimat Fjord System is an important fisheries area and is the only fjord habitat on the British Columbia coast that...
Reconstructing the sensitivity of past climate to forcings, and of ancient glaciers and ice sheets to this climate, can allow us to better understand the range of climate and cryosphere behavior we may see in the coming centuries. The Arctic is a region of particular importance due to its well-documented...
Large igneous provinces (LIPs) and intraplate seamounts reflect of anomalous mantle melting and illuminate interior processes of the Earth. These features are in all ocean basins and show the mantle’s evolution over time, then can provide information on plate tectonic processes, such as plate motion over time, spreading ridge formation,...
The Pacific coast groundfish fishery is a diverse, important and lucrative commercial and recreational fishery. Part of this fishery’s monitoring process includes regular fishery-independent surveys for stock assessment. Although these fishery-independent surveys are cost-effective, they are susceptible to scientific uncertainty, and they do not currently sample in nearshore (water depth...
Magnetotellurics is used in two geologic settings on scales ranging from 1000-km tectonic structures to local features hundreds of meters wide. These areas are the Midcontinent Rift System (MRS) and its related mantle plume in the northern Midwestern United States and Newberry Volcano in central Oregon.
The MRS study uses...
The objective of this dissertation was to understand the physical mechanisms affecting inversion events in a complex forested mountain landscape. This work was motivated by the long-term studies of climate at the Andrews Forest, short-term studies of vertical temperature, light, wind, and moisture gradient in old-growth trees, and interest in...
In 2013, a large upper-ocean thermal anomaly formed in the Gulf of Alaska (GOA) with sea surface temperatures (SSTs) warmer than 4 degrees Celsius above the climatological norm. This warm anomaly persisted for the next three years and has been linked to downstream effects on North American climate and negative...
The focus of this dissertation is the analysis of submesoscale and finescale features measured at oceanic fronts and the role they play in the transport of heat and salt. Two different geographical areas were used to analyze this transport: one, an area on the western side of the North Atlantic...
Commercial fisheries are coupled human-natural systems that cross state borders and integrate private, public, academic sectors and interests. These systems integrate complicated relationships between coastal socioeconomics, resource management and environmental realms. Previous findings from West Coast-based studies have identified aging trends in commercial fisheries participation, commonly referred to as the...
Though numerous drought metrics have been developed by the research community, adoption of these metrics by water managers has been limited. The reasons for this vary, but some include mismatches in time scales and spatial scales between the metric supplied and the operational decisions (e.g. water managers often work within...
The largest source of uncertainty among climate models simulating the climate system response to increased atmospheric carbon dioxide concentrations is the cloud feedback, the amplification or dampening of the warming from the carbon dioxide forcing by clouds. Refining our knowledge of the cloud feedback is therefore essential to gaining a...
The literal distance inherent in online education can be an important difference between it and traditional classroom settings, such that proximate, on-site learning is thought to be where experiential, transformative education happens (Cohen, 2013). Yet it is possible that some of the most compelling, effective aspects of traditional, proximate education...
Modifications of an ocean model are described, as the objective for which the model was used changed to study the kinematics and dynamics of an eastern-boundary poleward undercurrent.
The vertical propagation of Coastal Trapped Waves (CTWs) due to subsurface ridges is explored with the help of linear numerical and analytical models. Results show that submerged ridges projecting from the shoreline can scatter a horizontally propagating single baroclinic mode Kelvin wave into both upward and downward propagating Kelvin wave...
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...
The south central Chilean margin is one of the most seismically active subduction zones on Earth, generating some of the largest earthquakes on the planet, including the largest ever recorded in 1960 near Valdivia, Chile (Mw 9.5). Using the 15 km streamer and 6600 in3 tuned seismic airgun array aboard...
This dissertation is concerned with the behavior of sulfur in intermediate-silicic arc magmas associated with subduction at convergent margins. In particular it focusses on oxidized, sulfur-rich magmas, the conditions at which they might reach sulfate saturation, and implications of sulfate saturation. It is divided into an investigation of natural samples...
Sea otters (Enhydra lutris) used to exist along coastlines throughout much of the North Pacific Ocean. During the Maritime Fur Trade, sea otters were extirpated from much of their historic range, including Oregon. There is renewed interest in reintroducing sea otters to Oregon. Managers seek improved understanding of the potential...
A carefully calibrated primitive-equation model from 41°N to 48°N is used to study the poleward undercurrent off the US west coast. Chapter 2 describes poleward flow over the slope from Eulerian and Lagrangian perspectives. The model is robust, in the sense of several characteristics being qualitatively consistent with observational and...
In Oregon, commercial fishing is estimated to contribute $544 million in income and 10,000 jobs per year to coastal communities. However not all fisheries are reaching their allocated quotas for catch. In 2017, 187.6 million pounds of non-whiting groundfish trawl quota worth $67 million was not attained, nearly three times...
Environmental crime around the world, such as trafficking in illegal timber, is directly related to political instability. Traffickers exploit weak, fragile, and chaotic political circumstances to illegally extract high-value commodities, challenging the extent to which conservation goals are achievable in resource rich developing countries. Rosewood is the largest traded endangered...
Currently, forecasts produced by the Oregon-Washington (OR-WA) Coastal Ocean Forecast System are constrained by assimilation of only surface observations. The 4-dimensional variational (4DVAR) data assimilation (DA) algorithm is utilized to combine the model and the data, with the time-independent forecast ("background'') error covariance B. In this study, two possible improvements...
Many marine bivalves are sensitive to ocean acidification (OA) stress and often show heightened sensitivity during brief early larval and post-larval life stages, potentially leading to population bottlenecks. Most of the evidence to date has been collected in laboratory experiments that focused on physiological responses at the organismal level under...
Oblique subduction of the Juan de Fuca plate beneath the North American plate characterizes the tectonic setting of the Pacific Northwest. North American plate deformation at the latitude of central Oregon consists of the clockwise-rotation of the Siletzia block in the forearc and the extensional Basin and Range province in...
Involuntary movement, also known as forced displacement, has affected millions of people worldwide. At the end of 20th century, approximately 80 million people had been displaced due to hydropower projects, including approximately 22.5 million people in China. Dam-induced migration not only causes material loss, such as loss of homes and...
The variability of coastal carbonate chemistry continues to provide significant hurdles for understanding interactions between anthropogenic and natural CO2 cycling and resultant effects on coastal acidification dynamics. Attribution of the anthropogenic component is vital for identifying the impacts of increasing atmospheric carbon on coastal habitats such as coral reefs, upwelling...
Numerous studies have explored how alluvial channel size and morphology are adjusted to different sediment and flow conditions, yet we still know very little about how and to what degree the flow regime controls channel form and processes. We use the term ‘channel form’ to refer to the size and...