Physical Sciences and Mathematics Commons^™

Identifying The Effects Of Alum Treatment On Water And Sediment Chemistry Of Two Lakes In Pierce County, Washington, Colin Glaze

Summer Research

Many freshwater and marine ecosystems are affected by hazardous algal blooms (HABs) each year, and the number is rising. In most cases, the main cause of HABs is nutrient loading from anthropogenic sources, and often, the overloaded nutrient is phosphorus. To combat these HABs, alum treatment is commonly used. Alum treatment is the use of aluminum sulfate, which binds to phosphorus, effectively lowering the levels of free phosphorus and thus reducing algal growth. However, alum can also have adverse effects on water and sediment chemistry. Within Pierce County, Wapato and Waughop lakes present a unique opportunity to study the effects …

Petrology Of The Earliest Cascade Volcanic Units In Washington: The Northcraft, Tukwila, And Rattlesnake Mountain Formations And Implications For The Evolution Of The Cascade Arc, Louisa Cryan, Jeffrey H. Tepper

Summer Research

Cascade arc magmatism began ~45 million years ago, following the reconfiguration of the Farallon-North American subduction zone. This project seeks to classify the path of magmatism throughout the history of the Cascade arc, as well as categorize the earliest expressions of the Cascade arc. Three volcanic units, the Northcraft Formation (NF), Tukwila Formation (TF), and Rattlesnake Mountain Formation (RM) will serve as examples of the earliest Cascades-related lavas. Their categorization by field setting, geochemical characteristics, isotopic data, and age will create a better understanding of how Cascades magmatism began and developed over time.

Analysis has shown these units to contain …

Magnetic Exploration Of The Crescent Formation, Washington: The Search For A Hidden Fault Near Dusk Point, Samuel G. Furmanski

Summer Research

The mafic rocks of the Olympic Peninsula, Washington, are part of an accreted terrane known as Siletzia which experienced transpressional stresses as far as 50 Ma ago in the early Eocene. The Peninsula has an accretion-thrust marine sedimentary interior and a mafic volcanic periphery juxtaposed along the Hurricane Ridge fault; a terrane-scale thrust fault. The mafic Crescent Formation (CF) can be subdivided into two units: The Lower Crescent member (LC) and the Upper Crescent member (UC) as defined by Tabor and Cady (1978). The LC consists of submarine basalt flows that have composition similar to mid-oceanic ridges with zircon fission-track …

Petrology Of The Eocene Goble Volcanics, Southwest Washington: An Early Phase Of The Cascade Arc, Clara Phipps, Jeffrey H. Tepper

Summer Research

The Eocene Goble Volcanics (GV), comprised of >1000 km² of subaerial lavas and tuffs, are one of the most voluminous igneous formations in SW WA. Whole rock K-Ar ages of 45 to 32 Ma (Beck and Burr, 1979) suggest these rocks are an early expression of the Cascade arc, but their location is anomalous, lying between oceanic Crescent Fm basalts of the Siltezia terrane to the west and younger arc rocks to the east. The goals of this research are to determine the chemical and Sr-Nd isotopic traits of the GV and better establish the tectonic setting in which …

Geochemistry And Origins Of Thermal Springs Waters Of The Olympic Peninsula And Cascade Range, Washington, Jon Kenneth K. Golla

Summer Research

The state of Washington contains 98 low temperature (surface temperatures between ~ 20 - 50 ^oC) geothermal springs, which are powered by the convective circulation of groundwater that is heated by the natural heat of the Earth. These systems operate in a cycle that begins when precipitation percolates downward into the subsurface and comes in contact with a heat source. Subsequently the heated water returns to the surface, in most cases, having interacted chemically with rocks in the reservoir and/or along its ascent path. Surveys done by the USGS between the 1970s – early 1990s show there is significant …

Using Paleomagnetism To Unravel The Mysteries Of The Summit Creek Basalts, Glynis Bawden

Summer Research

The Summit Creek Basalts are a sequence of steeply dipping subaerial late Eocene basaltic flows located southeast of Washington’s Mount Rainier. Despite previous petrologic and paleomagnetic investigations, the origins of these basalts are poorly understood. It is uncertain whether they erupted in situ or were transported to their present location by tectonic processes. It is possible that these lavas were derived from the same magma source as a sequence of flows in the Crescent Formation on the Olympic Peninsula, as both erupted between 45 and 50 million years ago and have similar chemical compositions. A new paleomagnetic analysis of the …

Paleomagnetism Of Cascade Range Pleistocene Lava Flows Near Mckenzie Bridge, Oregon, Chelsea Jaeger

Summer Research

The purpose of this study is to examine geomagnetic field behavior recorded in a series of Pleistocene lava flows located near McKenzie Bridge, Oregon. Twenty-four sites, each consisting of at least ten samples were collected during July of 2011 and 2012. Alternating field (AF) and thermal demagnetization studies reveal normal, reversed, and possibly transitional polarities. Thermal demagnetization studies indicate the bulk of the magnetic signal is held in low titanium magnetite. Additional AF and thermal analysis is required to confirm transitional directions. In addition, polished sections will be prepared for optical examination to confirm the magnetic mineralogy of the samples.

Paleomagnetic Applications In Archaeology: Analysis Of Fire-Cracked Rocks At Camano Island Site, Tracy Anunsen

Summer Research

Both archaeological and paleomagnetic data (specifically thermal remnant magnetization, or TRM) are being utilized in an effort to determine the temperature of heating for fire-cracked rocks (FCRs) found at a pre-contact site on Camano Island in Island County, WA. If temperatures were high enough to reach the Curie temperatures of any magnetic minerals contained within the rocks, the resulting information may permit inferences as to the fuels used and the purpose of the fires. The Camano Island site is thought to be a later pre-contact Kikiallus site, containing shell debris and human remains in addition to the FCRs. Samples show …