Geology Commons^™

Debris Flow Susceptibility Map For Mount Rainier, Washington Based On Debris Flow Initiation Zone Characteristics From The November, 2006 Climate Event In The Cascade Mountains, Kassandra Lindsey

Dissertations and Theses

In November 2006 a Pineapple Express rainstorm moved through the Pacific Northwest generating record precipitation, 22 to 50 cm in the two-day event on Mt. Rainier. Copeland (2009) and Legg (2013) identified debris flows in seven drainages in 2006; Inter Fork, Kautz, Ohanapecosh, Pyramid, Tahoma, Van Trump, and West Fork of the White River. This study identified seven more drainages: Carbon, Fryingpan, Muddy Fork Cowlitz, North Puyallup, South Mowich, South Puyallup, and White Rivers. Twenty-nine characteristics, or attributes, associated with the drainages around the mountain were collected. Thirteen were used in a regression analysis in order to develop a susceptibility …

Quaternary Chronology And Stratigraphy Of Mickey Springs, Oregon, Leslie Allen Mowbray

Dissertations and Theses

Mickey Springs in the Alvord Desert, southeast Oregon, is analogous to other Basin and Range hydrothermal systems where the requisite conditions of heat source and permeable pathways are met through crustal thinning due to normal faulting. This study examines the morphology and lifespan of near-surface spring features through use of ground penetrating radar, thermoluminescence (TL) dating, and elevation modeling. Duration of hydrothermal activity at Mickey Springs has not previously been determined, and age determinations of sinter at the site are conflicting. The reason for and timing of this change in silica saturation in the hydrothermal fluid has not been resolved. …

Effects Of Aerial Exposure On Preservation Of Low-Temperature Calothrix Biosignatures In Silica Sinter From Queen's Laundry, Yellowstone National Park, Usa, Shana Kendall

Dissertations and Theses

Mineral-depositing hydrothermal ecosystems, such as the hot springs in Yellowstone National Park, provide an unparalleled opportunity to document how microbial biosignatures form and contribute to the body of evidence indicative of the microbial inhabitants of active hot springs. Mineralization of microbial communities in silica-depositing hot springs can result in the preservation of microbial biofacies in the geologic record. To determine the effects of prolonged aerial exposure on the preservation potential of mid-to-low temperature cyanobacteria dominated microbial communities that are typically permineralized in the siliceous sinter, modern biofacies samples of such communities were collected from the active and inactive parts of …

Hydrogeologic Investigation Of A Pumice Aquifer, Fremont/Winema National Forest, Oregon, Jonathan Michael Weatherford

Dissertations and Theses

The middle Holocene cataclysmic eruption of Mount Mazama blanketed Walker Rim, in south central Oregon, with 270 cm to 300 cm of pumice, causing capture of surface water systems by groundwater, stream relocation, and the formation of biologically diverse fens and seasonal wetlands. The pumice aquifer at Round Meadow, an 8.6 km² basin, hosts both a fen and seasonally ponded wetlands. The Round Meadow watershed lies within a closed basin between the upper Klamath and Deschutes river basins. As the highest meadow at Walker Rim, it is a relatively well-constrained system to study the effects of hydrological disruption.

A …

Glacier Change On The Three Sisters Volcanoes, Oregon: 1900-2010, Justin George Ohlschlager

Dissertations and Theses

A glacier responds to changes in climate by subsequent retreat and advance as a result of changes in snow inputs and outputs. Understanding these changes is important because shrinking glaciers limit and diminish local water resources. They contribute to alpine runoff in the late-summer months by delaying the maximum runoff until late in the melt season. A comprehensive glacier and perennial snowfield inventory has not been completed for the Three Sisters in Central Oregon. Using aerial photography, Digital Elevation Models (DEMs), previous studies, and historical ground based photographs these glacier and perennial snowfields were defined and their surface area change …

Naturally Occurring Background Levels Of Arsenic In The Soils Of Southwestern Oregon, Heather Ann Hurtado

Dissertations and Theses

This study examines the natural background concentrations of arsenic in the soils of southwest Oregon, using new samples in addition to data collected from previous theses (Khandoker, 1997 and Douglas, 1999). The original 213 samples were run by ICP-AES with a reporting limit of 20 ppm, and only three samples had detected values. The original samples were tested again (2013) at a lower reporting limit of 0.2 ppm by ICP-MS, as were 42 new samples (2013), to better ascertain the natural levels of arsenic in undisturbed soils. The aim is to add to the existing DEQ data set, which has …

Defining The Terroir Of The Columbia Gorge Wine Region, Oregon And Washington, Usa Using Geographic Information Systems (Gis), Hilary Whitney

Dissertations and Theses

The Columbia Gorge Wine Region (CGWR) is an emerging wine producing area that extends for about 100km along the Columbia River in Oregon and Washington State in which the number of vineyards, wineries and physical terroir conditions have yet to be defined. To better understand the physical factors affecting Oregon and Washington wine, this project analyzes climate, topography, geology and soil at vineyards in the CGWR. This was accomplished using Geographic Information Systems, existing earth science databases and field work. The region, which includes the Columbia Gorge American Viticulture Area (AVA) and the southwest portion of the Columbia Valley AVA, …

Landforms Along The Lower Columbia River And The Influence Of Humans, Charles Matthew Cannon

Dissertations and Theses

River systems, such as the Columbia River in the Pacific Northwest, USA have been influenced by human activities, resulting in changes to the physical processes that drive landform evolution. This work describes an inventory of landforms along the Columbia River estuary between the Pacific Ocean and Bonneville Dam in Oregon and Washington. Groupings of landforms are assigned to formative process regimes that are used to assess historical changes to floodplain features. The estuary was historically a complex system of channels with a floodplain dominated by extensive tidal wetlands in the lower reaches and backswamp lakes and wetlands in upper reaches. …