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Full-Text Articles in Physical Sciences and Mathematics

Defining Biodiversity: A Local Assessment Of The Tahuayo River, Peru Using Self-Directed Photography, Rozsika D. Steele Jan 2016

Defining Biodiversity: A Local Assessment Of The Tahuayo River, Peru Using Self-Directed Photography, Rozsika D. Steele

All Master's Theses

The Área de Conservación Regional Comunal Tamshiyacu Tahuayo (ACRCTT), located in Loreto, Peru, protects 420,000 hectares of the Amazon basin. In 2009, the ACRCTT received formal government recognition after three decades of advocacy and conservation work by resident communities. Local resource users who live a subsistence lifestyle possess sophisticated Traditional Ecological Knowledge (TEK) that can be used to identify which constituents of biodiversity are culturally relevant. This information can help resource managers develop an operational definition of biodiversity. Self-directed photography is a research method that allows participants the opportunity to direct data collection and empowers them to visually communicate their …


Resolving Gnetum Evolutionary History, Angela Mcfadden Jan 2016

Resolving Gnetum Evolutionary History, Angela Mcfadden

All Master's Theses

Gnetum are non-flowering seed plants of the tropics, indigenous to South America, Africa, and Asia. This group of about 40 species is fascinating to botanists because it shares distinctive morphological characteristics with flowering plants, such as broad leaves, woody stems, and flower-like strobili. There are still questions surrounding the relationships within the genus of Gnetum. With that in mind, I focused my work on generating phylogenetic hypotheses, using two molecular data sets: a concatenation of over 60 different chloroplast genes (66,815 base pairs), and the whole chloroplast genome (128,772 base pairs). This allowed me to compare the two phylogenies …


Fluid Release During Eclogite Formation, North Qaidam Terrane, Western China, Jake M. Meyer Jan 2016

Fluid Release During Eclogite Formation, North Qaidam Terrane, Western China, Jake M. Meyer

All Master's Theses

Ultrahigh-pressure (UHP, depths ≳100 km) eclogite samples from the Dulan area of the North Qaidam Terrane, western China, preserve evidence of fluid release along a prograde pressure-temperature (P-T) path. Eclogite sample D126A, Grt + Omp + Qtz + Zo + Amp + Phe + minor Rt + Hem, contains garnet porphyroblasts that preserve strong Ca zoning, recording higher core values (Grs34), lower inner mantle values (Grs25), increasing outer mantle values (Grs28), and lower rim values (Grs26). Isochemical phase diagrams (pseudosections), assuming H2O saturation, produce a P-T path constrained by multiple …


Spatiotemporal Slip Rate Variations Along Surprise Valley Fault In Relation To Pleistocene Pluvial Lakes, Brian N. Marion Jan 2016

Spatiotemporal Slip Rate Variations Along Surprise Valley Fault In Relation To Pleistocene Pluvial Lakes, Brian N. Marion

All Master's Theses

Using mapped paleoshoreline features with high-resolution topographic data and obtained radiocarbon dates on paleoshoreline tufas, I documented precise fault offsets of dated features over the last 25 ka along the Surprise Valley Fault (SVF). Fault offset measured in three lake sections within Surprise Valley ranged from 3.6 m in the southern section to 14.4 m in the central section. The offset paleoshorelines are dated to the late Pleistocene (<22 >ka) and were formed during the latest impoundment of pluvial Lake Surprise since the last glacial maximum. Slip rates vary along strike, assuming a fault dip of 68° with 0.25 ± …


Applications Of Computational Geometry And Computer Vision, Joseph Lemley Jan 2016

Applications Of Computational Geometry And Computer Vision, Joseph Lemley

All Master's Theses

Recent advances in machine learning research promise to bring us closer to the original goals of artificial intelligence. Spurred by recent innovations in low-cost, specialized hardware and incremental refinements in machine learning algorithms, machine learning is revolutionizing entire industries. Perhaps the biggest beneficiary of this progress has been the field of computer vision. Within the domains of computational geometry and computer vision are two problems: Finding large, interesting holes in high dimensional data, and locating and automatically classifying facial features from images. State of the art methods for facial feature classification are compared and new methods for finding empty hyper-rectangles …


Hazard Identification And Coastal Stratigraphy In Crescent Harbor, Northeast Whidbey Island, Washington, Brian Ostrom Jan 2016

Hazard Identification And Coastal Stratigraphy In Crescent Harbor, Northeast Whidbey Island, Washington, Brian Ostrom

All Master's Theses

Crescent Harbor marsh, on northeastern Whidbey Island, records evidence of co-seismic land-level change 1825 to 1925 cal. yrs. BP. The lithostratigraphy and diatom microfossil assemblages reveal a marsh peat abruptly overlain by intertidal mud, indicating rapid subsidence. Analysis of the modern-day position of depositional facies indicates subsidence from a high marsh to a tidal-flat environment representing an estimated 1.7 m elevation change. The timing of subsidence fits within the dates of a rupture found on the nearby Utsalady Point fault between 1,100 and 2,200 years BP (Johnson et al. 2004). Likely, the stratigraphy at Crescent Harbor records the same event …


Investigating Taphonomic Changes Of Deposits And Modeling Of The 2010 Earthquake And Tsunami In South-Central Chile, Alexandra Carranco Ruiz Jan 2016

Investigating Taphonomic Changes Of Deposits And Modeling Of The 2010 Earthquake And Tsunami In South-Central Chile, Alexandra Carranco Ruiz

All Master's Theses

South-central Chile has an extensive written catalog of historic earthquakes and tsunamis, but such records can be subject to inconsistencies. Dated tsunami deposits are more objective data that provide hard evidence of past tsunamis. The inland extent of deposits from past tsunamis (paleodeposits) can be used in tsunami modeling to reveal characteristics of the source earthquake, but these deposits may have undergone taphonomic processes since initial deposition. Therefore, to determine how tsunami deposits change during burial and preservation and the potential limitations of using paleodeposits in modeling, I investigated the modern 2010 Mw 8.8 Maule earthquake and tsunami as …


Kinetic Decay Of A Polymer/Ink Complex As An O2 Indicator, Becca Hoene Jan 2016

Kinetic Decay Of A Polymer/Ink Complex As An O2 Indicator, Becca Hoene

All Master's Theses

Indicator inks are an important part of the continued consumption of packaged goods. This thesis is focused on understanding the kinetics and reaction mechanism for a unique indicator ink that is based upon the oxidation of indigotetrasulfonate (ITS) encapsulated in the polyelectrolyte poly(diallyldimethylammonium chloride) (polyDADMAC). Sodium bisulfite (NaHSO3) was used as the initial oxygen scavenger and to drive the reduction of the ITS. Studies were predominantly done in solution phase through the dilution of the ink systems. Fluorescence spectroscopy was the primary method used to determine the kinetic decay rates and interaction between the ITS dye molecules and …


Documenting Mantle And Crustal Contributions To Flood Basalt Magmatism Via Computational Modeling Of The Steens Basalt, Southeast Oregon, Sylvana J. Bendaña Jan 2016

Documenting Mantle And Crustal Contributions To Flood Basalt Magmatism Via Computational Modeling Of The Steens Basalt, Southeast Oregon, Sylvana J. Bendaña

All Master's Theses

Flood basalts are enormous volcanic events with volumes of volcanic cover and intrusive equivalents that are affected by and significantly affect the crust. Steens Basalt represents 31,800 km3 of flood basalt lavas that erupted in eastern Oregon ~16.8 Ma in less than 300,000 years. Analytical data of flows from a 1 km vertical exposure at Steens Mtn. documents time-transgressive changes in composition of two geochemically distinct units: (1) lower Steens, MgO-rich lavas with lower incompatible trace element concentrations and 87Sr/86Sr, and (2) upper Steens, MgO-poor, with higher incompatible trace element concentrations and 87Sr/86Sr. …


Evolution Of A Flood Basalt Crustal Magmatic System: In Situ Mineral Data And Computational Modeling Of The Steens Basalt, Megan Graubard Jan 2016

Evolution Of A Flood Basalt Crustal Magmatic System: In Situ Mineral Data And Computational Modeling Of The Steens Basalt, Megan Graubard

All Master's Theses

Flood basalts are gigantic basaltic eruptions that modify the mass of the crust via intrusion of mantle-derived magma, and change its composition through interaction between magma and crust. The Steens Basalt, located in southeast Oregon, erupted approximately 16.8 million years ago, and is the oldest member of the Columbia River Basalt Group, the youngest and best-exposed flood basalt province on Earth. The Steens Basalt has an eruption volume of approximately 31,800 km3 and the duration of eruption is estimated to be between ~50,000 and 300,000 years. Major- and trace element whole rock data from 111 stratigraphically controlled samples from …


The Life Cycle Of Dams: An Analysis Of Policy Change On The Rogue River, Oregon, Wendy Mcdermott Jan 2016

The Life Cycle Of Dams: An Analysis Of Policy Change On The Rogue River, Oregon, Wendy Mcdermott

All Master's Theses

Every river system contains a unique set of attributes including biophysical characteristics, human created infrastructure, and stakeholder user groups. This thesis utilizes Lowry’s (2003) “Theoretical Framework for Policy Changes” to provide an analysis of fundamental policy change that occurred on the Rogue River in southwest Oregon through a comparative case study of the removal of two dams: Savage Rapids Dam (SRD) and the Gold Ray Dam (GRD). Fundamental change occurs when political receptivity is high and physical complexity is low. Political receptivity characterizes how decisions are made and physical complexity refers to how complicated implementing the decision may be. Application …


The Role Of Fire In Montane Forest Environments In The Willamette National Forest, Oregon, Tamara G. Cox Jan 2016

The Role Of Fire In Montane Forest Environments In The Willamette National Forest, Oregon, Tamara G. Cox

All Master's Theses

High-resolution charcoal and pollen analyses were used to reconstruct a 16,000-year-long fire and vegetation history of the Blair Lake watershed in the Willamette National Forest of Oregon. The record shows that during the late glacial period, overall fire frequency was relatively low. Pinus and Abies were the dominant vegetation, along with Pseudotsuga and Alnus, suggesting that an open-canopy conifer forest developed soon after the area was glacier free. Fire frequency increased during the early Holocene. Warmer and drier conditions are reflected in the herbaceous vegetation, Artemisia, Poaceae, and Cyperaceae, suggesting that meadows or other openings were part of …