Physical Sciences and Mathematics Commons^™

Late Pleistocene Deglaciation History At Point Partridge, Central Whidbey Island, Washington, Cynthia A. Carlstad

WWU Graduate School Collection

The study area contains a record of deglaciation events that has not been recognized elsewhere in the Puget Lowland. This record includes both subaerial outwash and glaciomarine deposition. The geologic history of the study area during recession of the Vashon ice sheet is marked by the following events:

1. Deposition of a kame delta complex from grounded ice probably located in Penn Cove and west of Point Partridge. This delta complex was built into marine water with a sea-level at approximately 55 meters. Eventually, ice drained by the outwash streams stagnated in the Point Partridge kettle region.
2. Isostatic rebound of the …

Regional Significance Of The Tonga Formation, North Cascades, Washington, Kathleen (Kathleen Maura) Duggan

WWU Graduate School Collection

The Tonga Formation of the North Cascades, Washington, is spatially situated between rocks of the crystalline core and those of the Northwest Cascades System. Its affinity to one or the other, or both, of these flanking units has been uncertain but is of importance to orogenic models for the region.

The Tonga Formation consists of weakly-deformed bedded feldspathic graywackes and shale metamorphosed at chlorite to staurolite grade. Comparison of protolith lithologic assemblage and Rb/Sr isotopic signature in addition to plutonic, metamorphic, and deformational histories suggests that the Tonga Formation is correlative with the Chiwaukum Schist and is not equivalent to …

Petrology And Structure Of The Eldorado Peak Area, North Cascades, Washington, Dan (Daniel Phelan) Mcshane

WWU Graduate School Collection

In this thesis the problem of the timing and mechanism of orogeny in the Skagit Gneiss of the North Cascades, Washington, is addressed by investigating plutonism and metamorphism in the vicinity of Eldorado Peak.

The primary finding of this project is that the 88-90 Ma Eldorado pluton was intruded, not faulted, into the Cascade River Schist and Skagit Gneiss. Intrusion is indicated by cross-cutting of foliations in country rock by the pluton, apophyses of Eldorado pluton in the country rock, and xenoliths of local country rock in the pluton. Detailed mapping shows that the Eldorado pluton does not cross-cut younger …

A Geographical Analysis Of Aquaculture Sites In Puget Sound, Dennis R. Gillespie

WWU Graduate School Collection

Attempts to promote aquaculture in Puget Sound waters have met with heated debate over the physical and environmental impacts such siting would produce. These are concerns that aquaculturists contend are nothing more than smoke screens used to conceal the only issues that matter to their opponents — aesthetic appearance and the potential threat to property values.

This essay examines the issues concerning aquaculture in the region. First the history of aquaculture in the Sound from the turn of the century through to the present is addressed. Highlighted are the problems of stewardship and the challenges faced by the industry in …

Metamorphism And Plutonism Of The Mt. Buckindy – Snowking Region, North Cascades, Washington, Steve M. (Steven Milton) Fluke

WWU Graduate School Collection

The focus of this study is on the metamorphism, plutonism, and structures of the Mt. Buckindy-Snowking region of the North Cascades crystalline core.

In a 15 by 30 km region in the northwest portion of the crystalline core, Cretaceous plutons in a northwest-southeast belt intrude rocks of the Napeequa unit. Metamorphic grade in the country rock ranges from lower greenschist facies in the northwest to amphibolite facies in the southeast. Thermobarometry applied to the equilibrium assemblages garnet-biotite-muscovite-plagioclase and garnet-homblende- plagioclase defines orogen-normal isobars varying from less than 4 Kb in the northwest to over 9 Kb in the south.

Plutons …

Paleomagnetism And Tectonics Of The Crescent Formation Northern Olympic Mountains, Washington, Andrew C. (Andrew Clyde) Warnock

WWU Graduate School Collection

Use of a small-diameter core drill has allowed the paleomagnetic sampling of the rims of fractured pillow basalts of the lower Crescent Formation in the northern Olympic Mountains. The pillows selected have spherical or oblate morphologies which typically develop on horizontal or mildly-dipping surfaces. Pillow keel structures and sedimentary interbeds were used to obtain bedding attitudes and top directions for use in structural corrections. All specimens were subjected to progressive thermal demagnetization. After removal of a low blocking-temperature recent overprint, stable endpoints were reached by 580°C in 11 of the 33 sites sampled (large within-site scatter was commonly observed in …

The Sedimentology, Petrology, And Tectonic Significance Of The Middle Eocene Flattery Breccia, Lyre Formation, Northwestern Olympic Peninsula, Washington, Alice Benkovich Shilhanek

WWU Graduate School Collection

The Flattery breccia, an informally designated unit within the middle Eocene Lyre Formation, consists of sedimentary breccia and conglomerate exposed at Cape Flattery, located at the northwestern point of the Olympic Peninsula, Washington. The Flattery breccia was deposited during the late Narizian, approximately 44 to 42 Ma.

The boulder- through sand-size detritus of the Flattery breccia and western Lyre Formation, which changes in texture along strike, were deposited by sediment- gravity flows, such as surging high-density turbidity currents and sandy debris flows. Interfingering alluvial fan-deltas, interfingering lobes of coarse detritus on a submarine fan, or resedimented wedges of coarse-grained detritus …