Understanding the degree to which topography of erosional landscapes in active mountain belts encode the rates and patterns of active deformation in the upper crust is a primary goal in the field of tectonic geomorphology. In particular, the convolved influence of variations in rock mass quality and the erodibility of...
The nature of upper plate deformation along the Cascadia subduction zone (CSZ) is poorly understood. Systematic covariation among topographic relief, geodetically determined uplift rates, decadal to millennial erosion rates, and the frequency of episodic tremor and slip (ETS) along the Cascadia forearc suggest a genetic association between forearc topography and...
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...
The Eastern California Shear Zone (ECSZ) is a broad zone of dextral shear inboard of the North American - Pacific plate boundary. Despite decades of study, the significance of a mismatch between geodetic velocities and geologic fault slip rates across the ECSZ remains incompletely understood. Geodetically determined interseismic strain across...
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...
The Hi-CLIMB broadband seismic experiment (2002-2005) operated 233 stations along an 800 km long north-south line from the Himalayan foreland into the central Tibetan Plateau and in a 350x350 km sub-array within southern Tibet and central and eastern Nepal. Station spacing was approximately 8 km along the line and 50...
To investigate the dynamic response of the outer accretionary wedge updip from the patch of greatest slip during the Mw8.8 2010 Maule earthquake, 10 Ocean Bottom Seismometers (OBS) were deployed from May 2012 to March 2013 in a small array with an inter-instrument spacing of ~10 km. Nine instruments were...
Measuring surface heat flow at the Hikurangi Trough is key toward characterizing the local thermal regime and the influence of thermally sensitive processes such as fluid flow and slow slip. Marine heat flow data were collected during May– June 2015 in the northern Hikurangi Trough at sites seaward and landward...
This thesis consists of three studies to better understand the environmental sustainability potential for algal-based biofuels. Initially, a comparison of recent life cycle assessments (LCA) of theoretical full-scale algal biofuel facilities was developed. These studies include varying boundaries and scope, functional units, and technology maturity assumptions. The comparison converted results...
University supervisors are critical to improvement in K-12 teaching and learning due to their roles in designing field experiences, managing relationships, mentoring, and supervising teacher candidates. The encouragement, support, and feedback shared by university supervisors in respect to the teaching performance of teacher candidates is especially powerful, and is a...
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...
Discrete fault systems accommodate both N-S contraction and dextral shear in concert with clockwise rotational deformation of the North American plate above the Cascadia Subduction Zone. In Washington, the Yakima Fold and Thrust Belt (YFTB) accommodates N-S contraction as a series of ENE-WSW trending thrust faults and folds. NW-striking, predominantly...
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....
Marine and coastal sedimentary archives show that the Cascadia Subduction Zone can generate great earthquakes of ~M9, most recently in 1700 CE, yet we still know little of the impacts of these events inland of the Pacific coast. Inland lakes have recently been exploited for their use as paleoseismic records...
The Toba Caldera Complex is the youngest resurgent caldera in the last 100 kyrs, formed from four overlapping eruptions starting 1.2 Myrs ago. The last caldera-forming eruption, the Youngest Toba Tuff eruption, occurred ~74 kyrs ago, emitting 2800 km3 of ash and pumice into the atmosphere and forming the caldera...
Although variations in insolation and emergent feedbacks among soil moisture,
vegetation, and soil cohesion are commonly invoked to explain topographic asymmetry that
depends on aspect, few studies have directly quantified the efficiency of regolith transport along
hillslopes of opposing aspect. We utilize meteoric ¹⁰Be concentrations in regolith (n = 74)...
A fundamental debate exists regarding the geometry and depth extent of seismogenic faults in eastern Tibet. Along the Longmen Shan, geologic and seismic reflection data reveal a belt of low to moderate angle thrust faults, some of which may have been activated in devastating earthquakes in 2008 (Mw ~7.9, Wenchuan)...
This dissertation reports on four related, though separate projects. The first project details the process of carrying out a digitally augmented soil mapping (DSM) effort alongside an ongoing survey in Oregon's Ochoco National Forest (ONF) using a Random Forest algorithm. The second chapter describes a initial soil survey in Oregon's...
Tsunami loading can cause sediment instability, which can compromise the structural integrity of coastal buildings and infrastructure. To understand the process by which a tsunami can cause sediment instability, it is necessary to understand how the pore water pressure in the soil changes during tsunami loading. Tsunami run-up causes the...
Controversial end member models for the growth and evolution of the Tibetan Plateau demand quantitative constraints of the lithospheric rheology. Direct determinations of bulk crustal rheology, however, remain relatively sparse. Here we use the flexural rebound of lacustrine shorelines developed during the Lingtong highstand around Siling Co, in central Tibet,...
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, EricKirby, Kevin 128
P. Furlong, Kai Meng, Ruth Robinson and Erchie Wang. Earth and Planetary
Although geodetic measurements of interseismic deformation in interior Tibet suggest slow
strain accumulation, active slip along the right-lateral Gyaring Co Fault is suggested to be between 8
and 21 mm/yr. Reliable geologic constraints on the slip rate along this fault are sparse. Here we document
12 ± 2 m of...
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, central Tibet
Holocene slip rate along the Gyaring Co Fault, central Tibet
Shi, X., Kirby, E., Lu, H
In the Colorado Rocky Mountains, the association of high topography and low seismic
velocity in the underlying mantle suggests that recent changes in lithospheric buoyancy may have
been associated with surface uplift of the range. This paper examines the relationships among
late Cenozoic fluvial incision, channel steepness, and mantle velocity...
Controversial end member models for the growth and evolution of the Tibetan Plateau demand quantitative constraints of the lithospheric rheology. Direct determinations of bulk crustal rheology, however, remain relatively sparse. Here we use the flexural rebound of lacustrine shorelines developed during the Lingtong highstand around Siling Co, in central Tibet,...
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from Holocene shoreline
deflection around Siling Co
Shi, X., Kirby, E., Furlong, K. P., Meng, K
Although geodetic measurements of interseismic deformation in interior Tibet suggest slow
strain accumulation, active slip along the right-lateral Gyaring Co Fault is suggested to be between 8
and 21 mm/yr. Reliable geologic constraints on the slip rate along this fault are sparse. Here we document
12 ± 2 m of...
Full Text:
along the Gyaring Co fault, central Tibet
Xuhua Shi1*, Eric Kirby2, Haijian Lu3, Ruth Robinson4
Controversial end member models for the growth and evolution of the Tibetan Plateau demand quantitative constraints of the lithospheric rheology. Direct determinations of bulk crustal rheology, however, remain relatively sparse. Here we use the flexural rebound of lacustrine shorelines developed during the Lingtong highstand around Siling Co, in central Tibet,...
Although geodetic measurements of interseismic deformation in interior Tibet suggest slow strain accumulation, active slip along the right-lateral Gyaring Co Fault is suggested to be between 8 and 21 mm/yr. Reliable geologic constraints on the slip rate along this fault are sparse. Here we document 12 ± 2 m of...
Antarctic Ice Sheet mass balance and, hence, sea level change is affected by the floating extensions of outlet glaciers and ice streams that take up about 44% of the coastline (Drewry et al., 1982) and are referred to as "ice shelves". Ice sheet mass loss accelerates when these ice shelves...
Pleistocene drainage basin integration led to progressive excavation of
Tertiary-Quaternary sedimentary basins along the Yellow River in the northeastern Tibetan
Plateau. Cosmogenic burial dating of ancestral river deposits and basin fill from two key
watershed divides confirms a fluvial connection between basins at 0.5–1.2 Ma, prior to excavation
by the...
Subhorizontal lake shorelines allow a geodynamic test of the size and extent of a hypothesized paleolake in central Tibet, the East Qiangtang Lake (EQL), during the last interglacial period (marine isotope stage (MIS) 5e). Reconstructions based on relict lake deposits suggest that the EQL would have been ~400 m deep...
The idea that climatically modulated erosion may impact orogenic processes has challenged geoscientists for decades. Although modeling studies and physical calculations have provided a solid theoretical basis supporting this interaction, to date, field-based work has produced inconclusive results. The central-western Alborz Mountains in the northern sectors of the Arabia-Eurasia collision...
In the eastern Qilian Shan, a flight of fluvial terraces developed along the Jinta River valley are deformed across the Nanying anticline. Four individual fluvial terraces are preserved at different elevations above the river, and higher terrace treads are draped by systematically thicker aeolian loess. Optically stimulated luminescence dating of...
Organizations are significantly influenced by corporate cultures of the interacting organizations. Both the construction industry and engineered wood products (EWP) manufacturing industry are generally known for operating in a traditional environment maintaining conservative corporate cultures, which can create friction when they try to interact with a more liberal architectural industry...
Cosmogenic-burial and U-series dating, identification of fluvial terraces and lacustrine
deposits, and river-profile reconstructions show that capture of the Gunnison River by
the Colorado River and abandonment of Unaweep Canyon occurred between 1.4-0.8
Ma. This event led to a rapid pulse of incision unlike any documented in the Rocky
Mountains....
The appearance of detritus shed from mountain ranges along the northern margin of the Tibetan Plateau heralds the Cenozoic development of high topography. Current estimates of the age of the basal conglomerate in the Qaidam basin place this event in Paleocene-Eocene. Here we present new magnetostratigraphy and mammalian biostratigraphy that...
Although widely studied in many portions of North America, little is known about the specific habitat requirements of mallard ducks (Anas platyrhynchos) during the breeding season in western Oregon. I radio-marked 72 female mallards in the Willamette Valley of Oregon in March-April 1995-96 to document wetland habitat selection during pre-nesting...
Coastal and marine ecosystems in Latin America and the Caribbean are undergoing a rapid and drastic transformation. Dense human populations are concentrated in coastal areas, leading to increased coastal development, destruction of near-shore habitats, pollution, and overexploitation of marine resources. For most Latin American and Caribbean countries, the deterioration of...
The purpose of this study was to describe and explore the relationships between work and family domain characteristics, time-based work-family conflict (WFC), and turnover intention of agriculture teachers. This study sought to identify factors influencing agriculture teachers' turnover intentions. An additional focus of this study was to explore differences between...
Potentially relevant literature for the years 1990-1999 was identified by (a) conducting keyword searches of computerized bibliographic databases, especially CAB Abstracts and Aquatic Sciences and Fisheries Abstracts, (b) reading through the tables of contents of a few especially relevant journals, (c) searching the internet for pertinent bibliographies, and (d) to...
The purpose of this quantitative study was to identify factors that contribute to students' levels of global citizenship. Factors considered in this research include (a) race/ethnicity, (b) gender, (c), year in school, (d) age, (e), length of time abroad, (f) host family experience, (g), community service abroad, (h) more than...
Invasive plants have the potential to reduce the diversity of species in plant and animal communities. I examined the negative effect of two invasive wetland plants, purple loosestrife and reed canary grass, on the species richness and diversity of plant and moth communities within 24 wetland study sites in the...
Food security, economic opportunities, and other benefits provided by a healthy ocean are in jeopardy because of years of overexploitation of many fisheries, and the challenges will intensify in many locales as climate and the environment continue to change. The good news is that solutions are gaining traction. Mandates to...
The way of slip transformation and strain partitioning at the eastern termination of the Kunlun
fault system remains unclear, and the question of whether this fault system is an important part for
lateral extrusion of Tibetan crust is debatable. The Tazang fault is regarded as the easternmost
continuation of the...
The primary purpose of this study was to determine whether the 1981
recommendation by the Montana State Board of Public Education had in
fluenced actual implementation of sexuality education in that state.
The study also sought to describe sexuality education in Montana and to
assess perceptions of Montana public high...
Numerous investigations demonstrate that mantle convective processes such as upwelling affect the surface topography of the overriding plate. The surface expression of mantle flow has been coined ‘transient topography’. Transient topography in the North American plate is thought to result from a mantle thermal anomaly beneath the Yellowstone volcanic center,...
Everyone involved in online education talks about community – what is it, how is it created, do students really want it? Most researchers now agree that online education is enhanced through a greater sense of community within the online classroom; however, the factors that make for a substantive and quality...
Treatment of extrahepatic portosystemic shunts provides many options, including cellophane banding. These cellophane bands are secured with a ligation clip. Weck® offers two forms of these: the stainless steel Hemoclip, and the polymer Hem-o-lok. This in vitro study compares the mechanical strength of these two of types of clips by...
The purpose of this study was to examine the attitudes
of primary teacher trainees toward sexuality education as a
component of family life education in Kenya. The study was
designed to determine the relationship between attitudes
toward sexuality education and teacher trainees knowledge
regarding sexuality education. The study was also...