Physical Sciences and Mathematics Commons^™

Stratigraphy And Sedimentology Of The Pipestone Canyon Formation, North Central Washington, James Jenner Peterson

WWU Graduate School Collection

Since Mesozoic time, the western margin of North America has grown through the addition of tectonic terranes, transported atop the subducting paleo-Pacific oceanic plate. The “Baja British Columbia” terrane model postulates accretion of the Insular superterrane at the latitude of southern Mexico and subsequent, margin-parallel translation north to juxtaposition with the western portion of the Intermontane superterrane. After amalgamation, the composite block continued north to its current location. The timing of the proposed translation has not bear well constrained. In the study area, the Okanogan Range batholith of the Intermontane superterrane’s Quesnellia terrane is juxtaposed with the sedimentary and volcanic …

A Fluid Inclusion And Structural Analysis Of The West Chance Vein System, Sunshine Mine, Kellogg, Idaho, David S. (David Scott) Boyer

WWU Graduate School Collection

The Sunshine mine, near Kellogg ID, is a mesothermal Ag-Pb vein deposit in the Coeur d’Alene mining district. Proterozoic siliciclastic rocks of the Ravalli Group, Belt Supergroup, host the ore bodies. The recently discovered West Chance ore body has been under development for the past five years. This tabular ore body strikes west and dips steeply to the south, has 300m (~1000 ft) strike length and extends approximately 914m (~3000 ft) down dip. Ore is located where the WNW-striking Chance fault changes to a predominately west-striking structure. This study consists of a fluid inclusion and structural analysis of the West …

Seismic Characterization Of The Northern Puget Lowland, Washington, Lori K. (Lori Kelly) Roberts

WWU Graduate School Collection

Records show that thousands of earthquakes have occurred in the northern Puget Lowland since 1969. At least fifteen of these events have been greater than magnitude 4, and one (Deming mag. 5.2, 1990) was the second largest recorded shallow crustal event in Washington for the last hundred years. Despite the evidence that suggests that the potential for great earthquakes capable of severe damage in the northern Puget Lowland is very real, the seismicity in the area is poorly understood. This is in part due to the wide scattering and apparently random assortment of recorded events. This thesis attempts to create …

Structure And Metamorphism Of The Talc Creek Area, Harrison Lake B.C., Minda L. Troost

WWU Graduate School Collection

The Slollicum and Cogburn terranes, metamorphosed country rock within the southern Coast Plutonic Complex, are juxtaposed along a thrust fault together with large slabs of ultramafic rock. The structure and metamorphism along and near this fault are the focus of this study.

Three periods of deformation (D₁-D₃) affected the study area. D₁ structures consist of penetrative foliation and lineations that are attributed to thrust stacking of the Slollicum and Cogburn terranes. Foliation, which parallels the fault contact, dips to the northeast at moderate to steep angles. Lineations have mainly down-dip orientations. D₂ structures record …