Physical Sciences and Mathematics Commons^™

The Effects Of Urbanization On The Water Balance Of The Fishtrap Creek Basin, Northwest Washington And South Central British Columbia, Charles S. (Charles Steven) Lindsay

WWU Graduate School Collection

The Fishtrap Creek basin is located in northwest Washington State and south central British Columbia. Land use in the basin is predominantly agricultural. Moderate urbanization in the past thirty-five years has increased impervious surface area in the basin from 1.8 to 8.0 percent. Monthly water balances were derived in order to quantify the effect of changing land use on the discharge of Fishtrap Creek. Stream discharges calculated from these water balances, constructed for 1952 through 1953 and 1987 through 1988, compare well with measured monthly and annual stream discharges. The favorable comparison indicates that the water- balance variables are in …

Changes In Grain-Size Distribution In A Gravel-Bed Stream Due To A Point-Source Influx Of Fine Sediment, John A. (John Andrew) Maloy

WWU Graduate School Collection

The bedload of a gravel-bed stream was sampled from two reaches, one upstream and one downstream of a large (1.0x10⁶ m³ of material removed) landslide, in order to assess the change in particle-size distribution caused by the influx of the finer-grained landslide material. For sampling purposes, the bedload was initially stratified on the basis of apparent grain size variability into 11 strata, or channel map units. Surface and subsurface materials were sampled independently. Subsurface sample sites were selected using stratified random sampling, with 30 sites upstream and 36 downstream of the landslide. Sampling techniques were modified from Church …

The Deforest Creek Landslide And Sediment Transport In Deer Creek, Skagit County, Washington, John N. (John Nevin) Thompson

WWU Graduate School Collection

Unit stream power, stream power per unit channel length, and total boundary shear stress were used to assess probable zones of river-sediment transport and storage following a large landslide into the Deer Creek basin, Skagit County, Washington. Since an initial deep-seated failure in glacial deposits in 1983 and a larger failure in 1984, the DeForest Creek landslide has introduced fine (±75% finer than coarse sand) sediment into the main channel of Deer Creek. The influx of sediment has caused infilling of void space in channel gravel by sand and silt, increased bank erosion, and increased slump activity adjacent to the …

The Geology And Petrology Of The Fifes Peak Formation In The Cliffdell Area, Central Cascades, Washington, Brad A. (Bradley Allen) Carkin

WWU Graduate School Collection

The Fifes Peak Formation in the Cliffdell area is comprised of two structurally, lithologically and geochemically distinct members separated by a pronounced unconformity. The older member (Edgar Rock member) is comprised of highly brecciated lava flows, coarse laharic breccia and lesser volcaniclastic sediments and tuffs. A thickness of at least 1,800 m is exposed near Edgar Rock. K-Ar ages indicate a latest Oligocene age of about 24 to 27 Ma. Lava compositions range from basalt to dacite, but are mostly basaltic andesite. These lavas are typically highly porphyritic and contain an anhydrous phenocryst assemblage of plagioclase, olivine, minor clinopyroxene and …

Mid-Tertiary Volcanic Rocks Of The Timberwolf Mountain Area, South-Central Cascades, Washington, Julianna M. (Julianna Maureen) Shultz

WWU Graduate School Collection

Over 3000 m of mid-Tertiary Cascade arc volcanics are exposed in the Timberwolf Mountain area of Washington's central Cascade Range. Arc rocks of the Ohanapecosh, Stevens Ridge, and Fifes Peak Formations overlie the Jura-Cretaceous Rimrock Lake inlier and sparse late Eocene(?) sedimentary rocks. Geochemical analyses of meta-basalts from the Russell Ranch and Indian Creek complexes that comprise the inlier indicate an island-arc or immature continental volcanic-arc tectonic environment for the inlier.

The early to mid Oligocene Ohanapecosh Formation is comprised of two facies within the study area. Distal, water-lain andesitic to dacitic lapilli-tuffs of the Wildcat Creek facies unconformably overlie …

The Depositional Environment, Petrography, And Tectonic Implications Of Informally Named Middle To Late Eocene Marine Strata, Western Olympic Peninsula, Washington, Benjamin Nickolas Adams

WWU Graduate School Collection

The informally named marine strata examined in this study comprise fault bounded slivers of middle to late Eocene (Ulatizian to Narizian) siltstone, sandstone, and conglomerate exposed on the northwestern Olympic Peninsula. The strata are divided into three lithofacies: the sandstone of Bahobohosh, the siltstone of Waatch Point and the siltstone and sandstone of Bear Creek by Snavley et al. (1986). Six facies have been identified consisting of strata deposited by high- and low-density turbidites, storm waves, slumping, tidal or littoral currents, and debris flows. Relationships among the facies indicate shallow marine deposition that shoaled from below to above storm wave-base …