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Stratigraphic Relationships Of The Tillamook Volcanics And The Cowlitz Formation In The Upper Nehalem River-Wolf Creek Area, Northwestern Oregon, Michael Keith Jackson
Stratigraphic Relationships Of The Tillamook Volcanics And The Cowlitz Formation In The Upper Nehalem River-Wolf Creek Area, Northwestern Oregon, Michael Keith Jackson
Dissertations and Theses
The upper Nehalem River-Wolf Creek area is located on the northeastern flank of the Tillamook Highlands in the northern Oregon Coast Range. Three rock stratigraphic units underlie the thesis area, and these units range from late Eocene to Oligocene in age.
The Stratigraphic Relationships Of The Columbia River Basalt Group In The Lower Columbia River Gorge Of Oregon And Washington, Terry Leo Tolan
The Stratigraphic Relationships Of The Columbia River Basalt Group In The Lower Columbia River Gorge Of Oregon And Washington, Terry Leo Tolan
Dissertations and Theses
The purpose of this study was to produce a detailed geologic map of the CRBG in the western portion of the Columbia River Gorge (fig. 1). The objectives were (1) to identify and delineate the extent of the Priest Rapids Member and Pomona Member intracanyon flows, and (2) to define the relationship of post-CRBG units to the CRBG intracanyon flows.
A Preliminary Investigation Of The Lithological Characteristics Of The Troutdale Formation In Portions Of The Camas, Sandy, Washougal, And Bridal Veil Quadrangles, David Lee Cole
Dissertations and Theses
The study area encompasses a region of about 80 square kilometers, centered about Corbett, Oregon. Sieve analyses suggest that the Troutdale Formation is composed of a conglomerate, a coarse-grained sandstone, and a siltstone lithofacies. Measured sections data show that 56 to 60 percent of the Troutdale Formation's exposures are composed of the conglomerate lithofacies. The coarsegrained sandstone lithofacies makes up 34 to 38 percent, while the siltstone lithofacies makes up only 4 to 8 percent. Pebble count data show that the representation of basalt varies from 69 to 100 percent, with an average of 85 percent, while quartzite varies from …
Stratigraphy, Lithofacies And Depositional Environment Of The Cowlitz Formation, T. 4 And 5n., R. 5w. Northwest Oregon, Dale M. Timmons
Stratigraphy, Lithofacies And Depositional Environment Of The Cowlitz Formation, T. 4 And 5n., R. 5w. Northwest Oregon, Dale M. Timmons
Dissertations and Theses
The Cowlitz Formation in southern Columbia and Clatsop counties, northwest Oregon was studied in order to prepare a geologic map of parts of this formation and to determine the character of its lithofacies and the environments of deposition.