Physical Sciences and Mathematics Commons^™

The Planet, 1990, Fall, Michael J. Lehnert, Huxley College Of The Environment, Western Washington University

The Planet

No abstract provided.

The Planet, 1990, Spring, Sara Olason, Associated Students Environmental Center, Western Washington University

The Planet

No abstract provided.

The Planet, 1990, Winter, Sara Olason, Associated Students Environmental Center, Western Washington University

The Planet

No abstract provided.

Danian (Paleocene) Molluscan Paleoecology In The Aftermath Of The Cretaceous-Tertiary Extinctions, East-Central Texas, Benjamin R. Farrell

WWU Graduate School Collection

Danian shelf sediments from the Brazos River region of east-central Texas span approximately the first two million years after the Cretaceous-Tertiary (K-T) extinctions with only minor changes in lithofacies. Study of these virtually continuous stratigraphic sections reveals the nature and timing of the molluscan faunal rebound in the wake of the K- T extinction event. Diverse Late Maastrichtian molluscan faunas were dominated by epifaunal suspension-feeders, primarily oysters. Immediately above the K-T extinction horizon, low-diversity molluscan assemblages were characterized by a bloom in the abundance of the pelagic herbivore family Litiopidae, which were rapidly replaced by a low diversity assemblage dominated …

The Similkameen Batholith Of North-Central Washington And South-Central British Columbia: The Petrotectonic Significance Of An Alkaline/Calc-Alkaline Magmatic Complex, Andrew M. (Andrew Mcnair) Buddington

WWU Graduate School Collection

The Similkameen batholith is a 170 Ma plutonic complex that contains coeval mafic alkaline and granitic calc-alkaline assemblages. The marginal mafic alkaline suite is silica-undersaturated, characteristically potassic in composition and comprised of malignite, shonkinite, and mafic syenites (+/- nepheline) with biotite and amphibole-bearing pyroxenite cumulates. The granitic plutons of the core are calc-alkaline, I-type, ranging from monzonite to granodiorite to granite in composition.

Structural and petrofabric studies indicate that the mafic alkaline suite was intuded and deformed by the calc-alkaline granitoids. Magmatic fabrics within the mafic rocks are concentric to the lithologic zonations and have been overprinted by sub-magmatic flow …

Petrology And Structure Of The Lookout Mountain - Little Devil Peak Area, North Cascades, Washington, Jeffrey A. Cary

WWU Graduate School Collection

The focus of this study is on the protolith types, metamorphism and deformation of the Cascade River Schist and related rocks in the Lookout Mountain - Little Devil Peak area of the North Cascades, Washington.

Two distinctive protolith assemblages are recognized in the Cascade River Schist, a volcanic arc assemblage in the Lookout Mountain area and an oceanic/forearc assemblage in the Little Devil Peak area. The volcanic arc sequence consists from the bottom up of andesitic to rhyolitic tuffs and flows, coarse-grained volcaniclastics and fine grained pelites. The lower tuff/flow unit grades downward into and is transitional with the underlying …

Relative Rise In Sea-Level During The Late Holocene At Six Salt Marshes In The Puget Basin, Washington, Harriet (Harriet Guthrie) Beale

WWU Graduate School Collection

Relative sea-level changes during the past several thousand years were determined at six marshes in three areas of the Puget Basin, Washington, to identify sites of vertical crustal movement, to provide data on regional relative sea-level history, and to collect data that may be used to monitor a proposed acceleration in the rate of eustatic sea-level rise due to global warming. Six salt marshes were cored to obtain radiocarbon ages of basal fossil peat deposits. Uncertainty in relating fossil marsh plants to elevations of former sea-levels reflects both the vertical range in which the plants occur today at the six …

Hydrostratigraphy And Groundwater Flow In The Sumas Area, Whatcom County, Washington, Sue Culton Kahle

WWU Graduate School Collection

Three types of groundwater systems occur within glacial sediments in a 10 mi² (25 km²) area near Sumas, Washington: an unconfined sand and gravel aquifer, a confined sand and gravel aquifer, and a generally unproductive clay aquitard. Water levels in the area were mapped from measurements of wells and points along stream courses in October 1988 and March 1989. The water-level configurations for the two aquifers roughly parallel surface topography. Water level maps were used to estimate direction of groundwater flow, which is generally to the southeast in the unconfined aquifer and to the northeast in the …

Tidal-Flushing Characteristics Of The Proposed Lummi Bay Marina, Whatcom County, Washington, William Morse Watts

WWU Graduate School Collection

Tidal-flushing of the proposed Lummi Bay Marina was studied using a physical model. The model was distinct from those of other regional marinas in that it included a berm around the edges, depth contours,sloping walls, and simulated mixed-semidiurnal tides. Spectrophotometric measurements of absorbance of dye in water resulted in the calculation of exchange-coefficients and flushing efficiency. Exchange coefficients in the physical model increased with increasing tidal range, suggesting a tendency for decreased water quality during smaller tides. Exchange was best in spring-tide simulations, but water tended to stagnate during the smaller ebb and flood cycles in both spring and neap …

A New Determination Of Pacific-Kula Relative Motions, Harold J. (Harold John) Cashman

WWU Graduate School Collection

A new method is presented and used to determine estimates of instantaneous relative motion vectors for the Pacific plate relative to the Farallon and Kula plates between magnetic chrons 34 and 24 (84 to 56 Ma). A weighted chi-square minimization technique was employed that has as input sequential magnetic anomaly picks taken from original ship-track profiles, and fracture-zone azimuths estimated from bathymetric control and offsets in magnetic lineations. Assignment of errors to the input data allows the use of critical chi-square limits to obtain confidence intervals on pole locations and their angular rates. Eleven distinctive magnetic anomalies chosen as control …

The 48-Year Sediment Budget (1942-1989) For Deer Creek Basin, Washington, Jerry (Jerry Arthur) Eide

WWU Graduate School Collection

A sediment budget for the Deer Creek basin (137 km²), northwest Washington, spans both pre- and post-management periods, and documents a significant increase in sediment production between 1942 and 1989. Sediment production was divided into four primary components: landslides, streambank erosion, hillslope erosion, and road-related erosion. Using field sampling of the four components, the amount of field time necessary to quantitatively describe the relative importance of the budget components is minimized. Five incremental sets of aerial photographs were used to construct a management history for the basin, to document time of initiation of landslides, and to document changes …

Plio-Pleistocene Stratigraphy And Tectonic Evolution Of The Northern Ohara Depression-Wakarara Range, North Island, New Zealand, Craig Fraser Erdman

WWU Graduate School Collection

Development of the Ohara Depression and uplift of the Ruahine and Wakarara Ranges followed an increase of the convergence rate between the Pacific and Australian plates. The Ohara Depression is a trough of Plio-Pleistocene sediments that crops out between the Ruahine and Wakarara Ranges. Two episodes of uplift during the late Pliocene and Pleistocene are recorded in the geologic record. Initial uplift occurred in the late Pliocene followed by subsidence through the early Pleistocene. The greatest uplift occurred during the mid-Pleistocene, and is recorded by deposition of a 200-250 m-thick conglomerate unit. Although compressional structures are present within and to …

Postfolding Remagnetization That Passes The Fold Test, Russ R. Burmester, Myrl E. Beck Jr., D. R. Bazard

Geology Faculty Publications

The palaeomagnetism of folded Cretaceous redbeds in the Methow-Pasayten belt of Washington was studied in an attempt to resolve the tilt versus translation origin of shallow inclinations found in most Cretaceous plutonic rocks of the Pacific Northwest. After elimination of results from apparently strained, overturned beds, correction to palaeohorizontal of the high-temperature, dominant components produced two distinct directions, one from each of two areas. Treated separately, the magnetizations from these two areas appear to pass the fold test. Both directions are anomalously shallow which is typical of the region, but the discrepancy between them casts doubt that both could have …

Phellinus Weirii Root Rot Of Douglas Fir In The Sehome Hill Arboretum: Distribution, Impact And Management Options, William G. (William Gary) Cantrell

WWU Graduate School Collection

This study examines the cause, distribution and impact of a forest pathogen within the 71 forested hectares of the Sehome Hill Arboretum in urban Bellingham, Washington. The causal agent was determined by the identification of cultures from decaying wood in douglas fir (Pseudotsuga menziesii (Mirbel) Franco) to be the root rotting basidiomycete Phellinus weirii (Muir.) Gilb. A ground survey of aboveground symptoms was used to detect 31 infection centers covering 6.64 hectares (9.2% of the Arboretum) of symptomatic trees. Infra-red aerial photography was used to determine canopy cover for deciduous and evergreen species. A forest canopy survey was …