CHRONOLOGY OF LATE QUATERNARY FAULTING
The Death ValleyFurnace Creek fault system shows evidence of multiple late Quaternary faulting events. The oldest faulting considered in this study is interpreted to be late Pleistocene in age. Holocene faulting events also are well documented, although possible historic faulting has been tentatively identified at only one locality.
Faulting thought to be late Pleistocene (Q2 age) occurs along the entire Death ValleyFurnace Creek fault system, and evidence for faulting believed to be Holocene was recognized in all sections of the fault system except the Salt Spring and Mustard Canyon sections of the Death Valley fault zone. Furthermore, along the Furnace Creek fault zone, right-lateral separation of geomorphological features thought to be late Pleistocene or younger is, in most places, greater than dip separation and was identified in all but the Sand Spring and Mesquite Flat sections. In contrast, along the Death Valley fault zone, small right-lateral separations were identified only on the Badwater turtleback and Copper Canyon sections.
Faulting Inferred to be late Pleistocene to middle Holocene (Q2 and Q1C age; older than 2,000 years)
Large, apparently continuous scarps, believed to be mostly Pleistocene in age, persist along the eastern base of the White Mountains from Indian Creek southward to Oasis (pl. 1A). North of Indian Creek, the most recently active fault traces diverge eastward from the range front into the basin of Fish Lake Valley. The range front north of Indian Creek is linear and may have been the locus of surface faulting during Pleistocene time, although large scarps in Holocene material have not been mapped in this area.
The largest scarps in inferred Pleistocene materials along the Furnace Creek fault zone are within the Dyer section (pl. 1A). These large scarps probably developed during several faulting events during late Pleistocene time, although direct evidence of multiple faulting has not been identified.
From Oasis southward to Sand Spring, the fault trace is well defined in the valley between the Last Chance Range and the Sylvania Mountains (pl. 1B); mountain fronts bordering the fault are interpreted to represent fault scarps that are probably as old as Tertiary.
In northern Death Valley, surface faulting along the main trend of the Furnace Creek fault zone is poorly defined in the Sand Spring section, although faults to the east of the trend of the main fault zone appear to displace late Pleistocene (Q2) surfaces. Holocene faulting may not have occurred within the northern Sand Spring section.
The Furnace Creek fault zone adjacent to and west of the Grapevine and Funeral Mountains (pls. 1C, 2) appears to have been faulted extensively during late Pleistocene time; fault-related features of inferred Holocene age are also common.
The Death Valley fault zone also appears to have been active during late Pleistocene time. High fault scarps modified by Lake Manly shorelines, which reached their high point about 10,000 years ago, attest to late Pleistocene fault activity in Death Valley. Faulting of inferred Holocene age appears to have continued along most of the Pleistocene fault scarps, except possibly in the Mustard Canyon section and along the western range front of the Black Mountains in the Artists Drive section (pl. 3) where scarps may be entirely of Pleistocene age.
At the south end of Death Valley (pl. 4), inferred Pleistocene faulting occurred as far south as the south Ashford Mill section of the study area and continued south along the Confidence Hills south of Shoreline Butte, beyond the area studied for this investigation.
Late Holocene Faulting (Q1B and Q1A age; younger than 2,000 years)
Several discrete faulting events inferred to be of late Holocene age are identified along the Death ValleyFurnace Creek fault system, although evidence for historic faulting remains equivocal. Evidence for four to six separate late Holocene faulting events along the Furnace Creek fault zone and three or more late Holocene events along the Death Valley fault zone are indicated by rupturing of Q1B surfaces. Most of these events cannot be correlated from one section to another, but events in the Horse Thief Canyon section of the Furnace Creek fault zone and the Golden Canyon section of the Death Valley fault zone appear to be younger than those in other sections.
Along the Furnace Creek fault zone, late Holocene faulting is believed to have occurred in all but the Chiatovich Creek, Sand Spring, Grapevine Canyon, and Redwall fan sections, and possibly the Oasis section. Geomorphically fresh features in the Horse Thief Canyon section are thought to be the youngest unequivocally fault induced features in the Furnace Creek fault zone. Small fissures found in 1969 in a manmade playa in the Oasis section may be related to faulting, although they did not form in association with a known seismic event.
Late Holocene faulting has certainly occurred along the Death Valley fault zone. In the Salt Springs area (pl. 3), a scarp displaces a lake shoreline that is approximately 2,000 years old. The full length of the faulting is unknown; only 2.3 km of the young scarp has been mapped, although it may extend for a length of 10 km into the salt pan west of Furnace Creek Ranch. The sinuous nature at the north end of the scarp suggests predominantly dip-slip movement.
In the Golden Canyon section (pl. 3) of the Death Valley fault zone, low scarps have free faces, probably representing at least two faulting events, in unvarnished alluvial materials interpreted as unit Q1B. These scarps are probably the youngest clearly fault related features of the Death ValleyFurnace Creek fault system and may be nearly historic. The system of young scarps has been mapped northward as far as Furnace Creek Ranch.
South of the Golden Canyon section along the western front of the Black Mountains, faulting of Q1B-age alluvium extends about 60 km to the south border of the study area. Scarps in inferred Q1B surfaces range in relief from less than 0.3 m to 1.5 m.
Last Updated: 24-Jul-2009