Twelve rock units, from upper Eocene to middle Miocene are exposed in the Nicolai Mountain-Gnat Creek area. They are, from oldest to youngest: Pittsburg Bluff Formation; Oswald West mudstone; Big Creek...

Six Tertiary rock units are exposed in the Bear Creek-Wickiup Mountain-Big Creek area. They are: the late Oligocene to early Miocene Oswald West mudstones; the Big Creek sandstone member, the Pipeline member (a...

Eight Tertiary sedimentary and volcanic units crop out in the thesis area. From oldest to youngest they are the: Sager Creek formation (informal); Pittsburg Bluff Formation; Northrup Creek formation (informal);...

The upper Eocene to lower Oligocene Oswald West mudstone is

The middle to late Eocene tholeiitic Tillamook Volcanics compose the oldest rock unit in the Hamlet-North Fork of the Nehalem River area. Geochemical plots and field relationships indicate that these rocks were...

The middle to upper Eocene Tillamook Volcanics form the volcanic core or basement rocks in the Rock Creek-Green Mountain area. They consist of a thick sequence of high TiO2 tholeiitic basalt, basaltic andesite,...

Six Tertiary units are exposed in the Onion Peak area near the town of Cannon Beach., Oregon. The units consist of: late Eocene to

Four distinct lithologic units compose the Tertiary rocks of the Neahkahnie Mountain - Angora Peak area, located along the northwest

Five distinct lithologic units compose the Tertiary rocks in the Tillamook Head - Necanicum Junction area of the northern Oregon Coast Range. They are: the late Eocene to early Miocene Oswald West mudstones,...

The middle Eocene Tillamook Volcanics form the oldest rock unit in the Elsie-lower Nehalem River area. K-Ar age determinations and age constraints imposed by foraminiferal and calcareous nannofossil assemblages...