Portland State University. Department of Earth Sciences
Robert O. Van Atta
Date of Award
Master of Science (M.S.) in Geology
1 online resource. Digitized typescript, Illustrations, maps.
Silt -- Oregon -- Tualatin Mountain region, Petrology -- Oregon
Topics in geology, which inevitably excite professional discussion and even tempered debate, often present challenging targets for the exploratory jabs of Master's degree candidates. The Portland Hills Silt and the controversy concerning its genesis provides just such an object.
Although the physical descriptions of the silt are generally in agreement, they remain somewhat generalized and, at present, no single definition is generally accepted. Moreover, incongruities concerning structural and textural details--notably, the presence of minor stratification and/or scattered pebbles in the silt--have resulted in considerable disagreement regarding its mode of origin.
Lentz, Rodney Thomas, "The Petrology and Stratigraphy of the Portland Hills Silt" (1977). Dissertations and Theses. Paper 2468.