All these formations were deposited in basins formed by Basin and Range low-angle extension; in the model presented here, the floor of these basins was in some areas the exhumed Basin and Range detachment surface. When the Death Valley pull-apart basin started to form ca. With the northwest strike of the turtleback structures, parallel to the inferred direction of strike slip, an origin of these features as a result of the strike slip is suggested.
Wright et al. Megamullions in oceanic crust have been mapped since the development of multibeam bathymetry in the s. The term is applied to large domed structures formed in inside-corner settings at the intersections of spreading centers and transform faults Tucholke and Lin, The structures are usually corrugated with mullion structures parallel to spreading direction and Tucholke and Lin relate them to continental metamorphic core complexes.
Tucholke and Lin compiled dimensional data on 17 oceanic megamullions. A simple average of their compilation yields dimensions of In Figure 11 a sinusoidal function with these dimensions is included in the cross section across Badwater. It is intriguing that the ocean megamullion matches fairly well with the shape of the basement surface of the Badwater turtleback.
Based on these comparisons, I suggest that the turtlebacks are megamullions formed as a result of strike-slip faulting in Death Valley. This means that the structures are young, created in the last 3 m. The turtlebacks are therefore formed of rocks that were exhumed due to extension and at the same time were intruded by a variety of igneous rocks.
They were then cut by strike-slip faults, forming the flanks of the Death Valley pull-apart basin. They also lie on the flank of a Proterozoic rift basin filled with Pahrump Group sediments, as mapped by Wright et al. This multiphase history of the structures plus their location along a preexisting rift may explain why the turtlebacks are unique features of the western North America extensional province. The interpretations presented above offer some new ideas for the evolution of Death Valley.
The Panamint Range, rather than being a large fault block detached from above the Black Mountains, is a core complex like the northern end of the range at Tucki Mountain. Basin and Range extensional allochthons occur along the east flank of the range; these formed during Miocene—Early Pliocene Basin and Range extension. Death Valley is a pull-apart basin, as originally proposed by Burchfiel and Stewart , formed in the last 3 m.
Prior to this time, a thick sedimentary sequence was deposited in what is now the northern Black Mountains, with early sedimentation being mostly volcanics. These volcanics were deposited partly on the exhumed detachment surface from the earlier phase of Basin and Range extension. The turtlebacks are megamullions very similar to megamullions adjacent to seafloor spreading centers.
The turtleback structures formed in the last 3 m. Fault dips along the southwest flanks of the turtlebacks are steep, e. The Death Valley region has played a key role in development of models of Basin and Range extension.
One of the data points used in structural restorations comes from a thrust complex, preserved in one of the Basin and Range allochthons in the northern Panamint Range, which correlates with a thrust complex of similar geometry in the Nopah Range Snow and Wernicke, In Snow and Wernicke's reconstruction, this correlation is used to restore the Panamint Range to a position adjacent to the Nopah Range.
The suggestion in this paper that the Panamints are not a far-traveled extensional allochthon means that this reconstruction must be reexamined. The correlation between thrust complexes is still valid, but instead of the entire Panamint Range being moved, only the extensional allochthons need to be moved. Further implications of this update will be discussed elsewhere.
The change from Basin and Range extension to strike slip between 8 and 3 Ma seen in the Death Valley region is very close to age ranges of changes in similar tectonic settings seen in several other localities in the ECSZ Stockli et al.
It also coincides with final opening of the northern Gulf of California and initiation of the southern portion of the San Andreas fault Dorsey et al.
The strong link between Pacific-North America plate motion and structural evolution of the ECSZ is emphasized by this synchronous timing. It would appear that, as the southern portion of the San Andreas fault joined up to the northern Gulf of California, the large-scale restraining bend in the San Andreas fault formed by the Mojave Block Fig.
Dave Reynolds, Larry Lawver, and especially an anonymous reviewer provided excellent suggestions for improving the manuscript. Regional topography of western North America, showing location of Death Valley and tectonic domains.
Topography is gray-shaded with illumination from the north for areas above sea level. Areas below sea level are in blue. Data from Smith and Sandwell Topography is colored with a nonlinear scale ranging from pale blues below sea level through greens and browns to white of the Sierra Nevada peaks. Labels are colored for visibility only. Tectonostratigraphic chart for the Death Valley area. To accommodate as many events as possible, the time scale from Gradstein et al.
From the left, the columns show the igneous events, stratigraphy, tectonic events, and regional tectonic regime. See Table 1 for data and explanations of abbreviations used. The stratigraphic column illustrates age ranges of named sedimentary formations, with different patterns indicating whether or not formations have been interpreted as syntectonic Snow and Lux, The Artist Drive Formation is shown by a different symbol as these rocks in their northern Black Mountains type area are primarily lava flows or volcaniclastics.
The naming convention for sedimentary formations follows that established by Hunt and Mabey and subsequently modified by Snow and Lux and Knott et al. In the stratigraphic column, formations from the north and west of the area are on the left so that left to right is equivalent to north and west to south and east. Geology of the Death Valley area, from Workman et al. Cross sections in Figures 6 , 8 , and 9 are labeled A, B, and C. Thickness of Cenozoic sediments from the digital compilation of Blakely and Ponce in color.
Dark red lines in Death Valley are faults from Blakely et al. Purple polygons Prot bsmnt are exposures of Proterozoic basement, generally denoting detachment footwalls, from Workman et al. Cross section across Tucki Mountain along profile A in previous location maps. This profile is close to the one shown by Hunt and Mabey It is derived from the topography Fig. Dashed line shows inferred location of the detachment fault across Tucki Mountain. Compiled from Wright et al.
Proterozoic basement consists of metamorphic basement and sediments of the Pahrump Group and Johnnie Formation. Late Proterozoic sediment in the hanging wall of the detachment consists of Wood Canyon Formation. Dashed line shows inferred location of the detachment fault across the Panamint Range. Tv—Tertiary volcanics. Schematic evolution of the cross section of Figure 9.
See text for details. The cross section of Figure 9 with, superimposed at Badwater, a generalized cross section across an oceanic megamullion structure megamullion data from Tucholke and Lin, Sign In or Create an Account. User Tools. Sign In. Advanced Search. Skip Nav Destination Article Navigation. Research Article February 01, Pickle Research Campus, Bldg.
Google Scholar. Geosphere 7 1 : — Article history received:. Figure 1. View large Download slide. TABLE 1. Volume 7, Number 1. Previous Article Next Article. View Full GeoRef Record. Paleoenvironments and paleohydrology of the Mojave and southern Great Basin Deserts. Search ADS. Cenozoic basins of the Death Valley extended terrane as reflected in regional scale gravity anomalies. Geology of Panamint Valley-Saline Valley pull-apart system, California: Palinspastic evidence for low angle geometry of a Neogene range-bounding fault.
Late Cenozoic crustal extension and magmatism, southern Death Valley region, California. Stratigraphy and tectonic implications of the latest Oligocene and early Miocene sedimentary succession, southernmost Funeral Mountains, Death Valley region, California.
Low-angle, range-flank faults in the Panamint, Inyo, and Slate ranges, California: Implications for recent tectonics of the Death Valley region. Structural characteristics of metamorphic core complexes, southern Arizona. Geologic and hydrologic investigations of a potential nuclear waste disposal site at Yucca Mountain, southern Nevada. Quaternary low-angle slip on detachment faults in Death Valley, California.
Geometry and timing of strike-slip and normal faults in the northern Walker Lane, northwestern Nevada and northeastern California: Strain partitioning or sequential extensional and strike-slip deformation? Late Tertiary and Quaternary geology of the Tecopa basin, southeastern California.
Footwall structural evolution of the Tucki Mountain detachment system, Death Valley region, southeastern California.
Structural unroofing of the central Panamint Mountains, Death Valley region, southeastern California. Basin and Range extensional tectonics near the latitude of Las Vegas, Nevada. Interpretation and tectonic implications of cooling histories: An example from the Black Mountains, Death Valley extended terrane, California.
Thermal and barometric constraints on the intrusive and unroofing history of the Black Mountains: Implications for timing, initial dip, and kinematics of detachment faulting in the Death Valley region, California. Exhumation of the Inyo Mountains, California: Implications for the timing of extension along the western boundary of the Basin and Range Province and distribution of dextral fault slip rates across the eastern California shear zone.
Constraints on the kinematics and timing of late Miocene—Recent extension between the Panamint and Black Mountains, southeastern California. Refined kinematics of the eastern California shear zone from GPS observations, — As Lake Manly evaporated, it left behind an abundance of evaporites, including sodium chloride, calcite, gypsum and borax.
Death Valley's salt flats are mostly made up of sodium chloride, but other evaporative minerals like calcite, gypsum, and borax are also found. When venturing out onto the salt flats at Badwater Basin, be sure to take water and wear a hat and sunglasses for the walk; the salt flats are a searing hot place for a hike.
The true lowest point is several kilometers to the west, but the sign makes for a safer photo-op. Turn around to see another famous sign: the human-made sea-level mark on the cliff high above the parking area. For thousands of years, the people of the Timbisha tribe thrived here, migrating seasonally between the valley floor and mountains.
One of the best places to experience Death Valley in all its multicolored glory is Zabriskie Point, preferably at sunrise. Most days, Zabriskie Point is bone dry, but during rare rainstorms, this soft rock erodes readily, creating intricately carved badlands. Zabriskie Point is known for its spectacular colors, especially at sunrise. The unusual colors here are the result of chemical weathering of different metals found in the rocks.
The reds and pinks come from oxidation of iron-rich hematite; the greens are from mica-rich volcanic ash deposits; and the purples from manganese. Red clay may have been of sacred interest to the Timbisha, but Europeans came to Death Valley looking for gold and silver. Lead, zinc, antimony, fluorite, cinnabar, epsom salts, mercury, tungsten, copper, talc, sodium chloride and manganese have also been found here, but the only rock ever mined in commercially successful quantities is borax.
Nicknamed white gold, borax is a mineral with a wide variety of uses in detergents, cosmetics and industrial manufacturing processes. Much of Death Valley's floor lies at or below sea level. Harmony Borax Works famously employed twenty-mule team wagons to haul borax out of the valley to Mojave, a sight immortalized by black and white photos on the front of the Twenty-Mule Team Borax Soap box. At the height, companies were mining up to three tons of borax a day.
In , Death Valley was declared a national monument, but mining was allowed to continue. In the late s, after open-pit and strip mining began to visibly scar the land, Congress passed the Mining in the Parks Act, which closed Death Valley to new mining claims and banned open-pit mining.
Underground mining continued on a more restrained scale through , when Death Valley became a national park, and finally ceased in , when the last underground borax mine was closed. Learn how scientists are working save these fish. You may need more than one visit to truly experience the park.
Death Valley is a vast national park with over 3 million acres of designated wilderness and hundreds of miles of backcountry roads. The park contains an amazing variety of terrain, historic sites, plants and animals for outdoor adventurers to discover on foot, by bike or in your car.
Death Valley has some of the darkest night skies in the country and is a great place to gaze in awe at the expanse of the Milky Way, see the details of the moon, track a meteor shower or simply reflect on your place in the universe. However you enjoy your time in the park, please remember to leave no trace , so everyone can enjoy Death Valley for generations to come.
Death Valley is full of life, from vibrant wildflowers and unique species to a cultured past and scenic landscapes. Which will you explore first? A stark day fades to evening at Badwater Basin. Photo by William Woodward www. A National Park Service volunteer poses next to the visitor center thermometer on a hot day. Photo by National Park Service. Desert gold wildflowers bloom across the landscape. Photo by Juliana Johnson www.
Rocks and their trails lit by the moonlight. Photo by Cat Connor www. The sun sets on the Mesquite Sand Dunes.
Photo by Alla Gill www. Roadrunner streaks across the terrain. A break in the clouds at twilight reveals the rugged terrain of the Devils Golf Course. Photo by Michel Hersen www. The colorful mountains of Artists Palette. Photo by Blair Radford www. Photo by Ken Lee www. View of Ubehebe Crater. Photo by Susan Johnson www. Bright blue Devils Hole Pupfish. Blog Post. From Wild Cats to Adventure Felines.
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