Structural character of the northern segment of the Paintbrush Canyon fault, Yucca Mountain, Nevada
- Science Applications International Corp., Golden, CO (United States)
- Geological Survey, Denver, CO (United States)
Detailed mapping of exposed features along the northern part of the Paintbrush Canyon fault was initiated to aid in construction of the computer-assisted three-dimensional lithostratigraphic model of Yucca Mountain, to contribute to kinematic reconstruction of the tectonic history of the Paintbrush Canyon fault, and to assist in the interpretation of geophysical data from Midway Valley. Yucca Mountain is segmented into relatively intact blocks of east-dipping Miocene volcanic strata, bounded by north-striking, west-dipping high-angle normal faults. The Paintbrush Canyon fault, representing the easternmost block-bounding normal fault, separates Fran Ridge from Midway Valley and continues northward across Yucca Wash to at least the southern margin of the Timber Mountain Caldera complex. South of Yucca Wash, the Paintbrush Canyon Fault is largely concealed beneath thick Quaternary deposits. Bedrock exposures to the north reveal a complex fault, zone, displaying local north- and west-trending grabens, and rhombic pull-apart features. The fault scarp, discontinuously exposed along a mapped length of 8 km north of Yucca Wash, dips westward by 41{degrees} to 74{degrees}. Maximum vertical offset of the Rhyolite of Comb Peak along the fault measures about 210 m in Paintbrush Canyon and, on the basis of drill hole information, vertical offset of the Topopoah Spring Tuff is about 360 m near the northern part of Fran Ridge. Observed displacement along the fault in Paintbrush Canyon is down to the west with a component of left-lateral oblique slip. Unlike previously proposed tectonic models, strata adjacent to the fault dip to the east. Quaternary deposits do not appear displaced along the fault scarp north of Yucca Wash, but are displaced in trenches south of Yucca Wash.
- Research Organization:
- American Society of Civil Engineers (ASCE), New York, NY (United States); American Nuclear Society (ANS), La Grange Park, IL (United States)
- OSTI ID:
- 60969
- Report Number(s):
- CONF-940553-Vol.4; TRN: 94:010821-0075
- Resource Relation:
- Conference: International high-level radioactive waste management conference, Las Vegas, NV (United States), 22-26 May 1994; Other Information: PBD: 1994; Related Information: Is Part Of High Level Radioactive Waste Management: Proceedings of the fifth annual international conference. Volume 4; PB: 1048 p.
- Country of Publication:
- United States
- Language:
- English
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