Preliminary geology of eastern Umtanum Ridge, South-Central Washington
The basalt stratigraphy and geologic structures of eastern Umtanum Ridge have been mapped and studied in detail to help assess the feasibility of nuclear waste terminal storage on the Hanford Site in southeastern Washington State. Eastern Umtanum Ridge is an asymmetric east-west-trending anticline of Columbia River basalt that plunges 5 degrees eastward into the Pasco Basin. Geologic mapping and determination of natural remanent magnetic polarity and chemical composition reveal that flows of the Pomona and Umatilla Members (Saddle Mountains Basalt), Priest Rapids and Frenchman Springs Members (Wanapum Basalt), and Grande Ronde Basalt were erupted as fairly uniform sheets. The Wahluke and Huntzinger flows (Saddle Mountains Basalt) fill a paleovalley cut into Wanapum Basalt. No evidence was found to indicate Quaternary-age movement on any structures in the map area. The basalt strata on the south limb of the Umtanum anticline display relatively little tectonic deformation since Miocene-Pliocene time. Thus, the buried south flank of Umtanum Ridge may provide an excellent location for a nuclear waste repository beneath the Hanford Site.
- Research Organization:
- Rockwell International Corp., Richland, WA (United States). Rockwell Hanford Operations
- DOE Contract Number:
- AC06-77RL01030
- OSTI ID:
- 6670539
- Report Number(s):
- RHO-BWI-C-21; TRN: 81-003804
- Country of Publication:
- United States
- Language:
- English
Similar Records
Rate of deformation in the Pasco Basin during the Miocene as determined by distribution of Columbia River basalt flows
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Related Subjects
58 GEOSCIENCES
BASALT
STRATIGRAPHY
WASHINGTON
GEOLOGY
COLUMBIA RIVER BASIN
FEASIBILITY STUDIES
GEOLOGIC DEPOSITS
HANFORD RESERVATION
MAPS
RADIOACTIVE WASTE DISPOSAL
IGNEOUS ROCKS
MANAGEMENT
NATIONAL ORGANIZATIONS
NORTH AMERICA
PACIFIC NORTHWEST REGION
ROCKS
US DOE
US ERDA
US ORGANIZATIONS
USA
VOLCANIC ROCKS
WASTE DISPOSAL
WASTE MANAGEMENT
052002* - Nuclear Fuels- Waste Disposal & Storage
580100 - Geology & Hydrology- (-1989)