New data are presented that provide evidence for the onset of extensional deformation in the Northwestern Basin and Range within 1 million years after the eruption of the Steens Basalt at 16.5 Ma. New geologic mapping (1:24,000), stratigraphic sections, and ⁴⁰Ar/³⁹Ar dating of the Crane Basin rocks provide a control...
The thesis area is located in the southeastern corner of Harney County, Oregon. This portion of Oregon is situated in the northern part of the Basin and Range province, and is characterized by both mafic and silicic extrusives, and localized nonmarine sediments and
tuffs ranging in age from middle (?)...
The thesis area consists of 44 square miles in southeast Harney
County, Oregon. The Pueblo Mountains are located in the northwest
part of the Basin and Range structural province, and are characterized
by normal faults of large displacement that produced the tilted fault
block mountain range.
The oldest rocks exposed...