Physical Sciences and Mathematics Commons^™

Stratigraphy, Diagenesis, And Depositional Environment Of The Cowlitz Formation (Eocene), Northwest Oregon, Leonard Carl Farr Jr.

Dissertations and Theses

The Upper Eocene Cowlitz Formation is exposed in surface outcrops southwest of the town of Vernonia, in Columbia County, Oregon. The Cowlitz Formation also occurs in the subsurface of the Mist gas field where its Clark and Wilson (C and W) sandstone member (informal) acts as a natural gas reservoir, and its upper Cowlitz mudstone member (informal) acts as a cap rock. Surface exposures and continuous core were studied in order to determine Cowlitz Formation stratigraphy, and its depositional environment. Fresh core samples were also studied petrographically, and with a scanning electron microscope, in order to determine the effects of …

The Stratigraphy Of The Scappoose Formation, The Astoria Formation, And The Columbia River Basalt Group In Northwestern Columbia County, Oregon, Nancy Tompkins Ketrenos

Dissertations and Theses

The study area is located in northwestern Columbia County, and covers an area of approximately 70 square kilometers. The purpose of the study was to investigate the possible correlation of the Scappoose and Astoria Formations and determine their stratigraphic relationship to the Columbia River Basalt Group through mapping, geochemistry and petrography.

Preliminary Investigation For Underground Storage Of Pipeline Gas In The Bruer And Flora Pools, Mist Gas Field, Columbia County, Oregon, Paul Joseph Townley

Dissertations and Theses

Northwest Natural Gas Canpany has proposed to convert the Bruer and Flora pools of the Mist Gas Field in west-central Columbia County, Northwestern Oregon, to pipeline gas storage reservoirs. Conversion to underground storage of pipeline gas in these depleted gas reservoirs would be the first in the Pacific Northwest. The Bruer and Flora Pools are fault trapped within the Cowlitz Formation. The shales overlying the Cowlitz Formation create a local seal for these gas reservoirs. X-ray diffraction and density log measurements suggest that the clay in these shales is primarily composed of smectite, which provides an excellent caprock seal.

The …