thumb|False color image of Death and Panamint valleys area from space. The smaller linear valley is Panamint Valley and the larger one is Death Valley. The mountain range between Death and Panamint valleys is the Panamint Range and the Black Mountains bound the other side of Death Valley. (NASA image)

The exposed geology of the Death Valley area presents a diverse and complex set of at least 23 formations of sedimentary units, two major gaps in the geologic record called unconformities, and at least one distinct set of related formations geologists call a group. The oldest rocks in the area that now includes Death Valley National Park are extensively metamorphosed by intense heat and pressure and are at least 1700 million years old. These rocks were intruded by a mass of granite 1400 Ma (million years ago) and later uplifted and exposed to nearly 500 million years of erosion.

Marine deposition occurred 1200 to 800 Ma, forming thick sequences of conglomerate, mudstone, and carbonate rock topped by stromatolites, and possibly glacial deposits from the hypothesized Snowball Earth event. Rifting thinned huge roughly linear parts of the supercontinent Rodinia enough to allow sea water to invade and divide its landmass into component continents separated by narrow straits. A passive margin developed on the edges of these new seas in the Death Valley region. Carbonate banks formed on this part of the two margins only to be subsided as the continental crust thinned until it broke, giving birth to a new ocean basin. An accretion wedge of clastic sediment then started to accumulate at the base of the submerged precipice, entombing the region's first known fossils of complex life. These sandy mudflats gave way about 550 Ma to a carbonate platform which lasted for the next 300 million years of Paleozoic time.

The passive margin switched to active margin in the early-to-mid Mesozoic when the Farallon Plate under the Pacific Ocean started to dive below the North American Plate, initiating a subduction zone; volcanoes and uplifting mountains were produced as a result. Erosion over many millions of years formed a relatively featureless plain. Stretching of the crust under western North America started around 16 Ma and is thought to be caused by upwelling from the subducted spreading-zone of the Farallon Plate. This process continues into the present and is thought to be responsible for producing the Basin and Range province. By 2 to 3 million years ago this province had spread to the Death Valley area, ripping it apart and giving birth to Death Valley, Panamint Valley and surrounding ranges. These valleys partially filled with sediment and, during colder periods during the current ice age, with lakes. Lake Manly was the largest of these lakes; it filled Death Valley during each glacial period from 240,000 years ago to 10,000 years ago. By 10,500 years ago these lakes were increasingly cut off from glacial melt from the Sierra Nevada, starving them of water and concentrating salts and minerals. The desert environment seen today developed after these lakes dried up.

Early sedimentation

Proterozoic complex

Little is known about the history of the oldest exposed rocks in the area due to extensive metamorphism. This somber, gray, almost featureless crystalline complex is composed of originally sedimentary and igneous rocks with large quantities of quartz and feldspar mixed in. The original rocks were transformed to contorted schist and gneiss, making their original parentage almost unrecognizable. Radiometric dating gives an age of 1700 million years for the metamorphism, placing it in the early part of the Proterozoic eon.

A mass of granite now in the Panamint Mountains intruded this complex 1400 mya. Pegmatic dikes and other widely spaced plutons of granite are also in the complex (a pluton is a large blob of magma deep underground and dikes are projections of that). Outcrops can be seen along the front of the Black Mountains in Death Valley and in the Talc and Ibex Hills. When the granite was being intruded, the west coast of North America ran through Eastern California and through an embayment that spread toward the Las Vegas Valley. This embayment, called the Amargosa aulacogen, had highlands north and south of it and was the result of a failed rift. Many thousands of feet of sediment filled the slowly subsiding basin.

Next, the metamorphosed Precambrian basement rocks were uplifted and a nearly 500-million-year-long gap in the geologic record, a major unconformity, affected the region. Geologists do not know what happened to the eroded sediment that must have overlain the complex, but they do know that regional uplift was responsible; the area was originally below the surface of a shallow sea.

Pahrump Group

thumb|View north across Saratoga Spring ponds to hills consisting of late Precambrian Pahrump Group rocks. White band is talc formed by reaction of dolomite with the black diabase enclosing it. A sill of diabase magma intruded between sedimentary layers of Crystal Spring Formation, now seen flanking the diabase at lower left. All units now tilt to east (right). The spring water rises along a fault and becomes ponded by fringing barrier dunes. (NPS archive image)

The Pahrump Group of formations were deposited from 1200 to 800 mya in the Amargosa aulacogen. This was after uplift-associated erosion removed whatever rocks covered the Proterozoic Complex. Pahrump is composed of, from oldest to youngest:

  • Crystal Spring Formation,
  • Beck Spring Dolomite,
  • Kingston Peak Formation.

Outcrops of this group can be seen in a highly metamorphosed belt that extends from the Panamint Mountains to the eastern part of the Kingston Range, including an area near the Ashford Mill site.

Uplift eventually exposed the crystalline complex to erosion. Arkose conglomerate and mudstone of the lower Crystal Spring Formation were formed from muddy debris derived from stream erosion of these uplands. A warm shallow sea spread over the area as the Amargosa aulacogen slowly subsided; thick sequences of lime-rich ooze with abundant colonies of algae called stromatolites were then laid down. Dolomite and limestone resulted, forming the middle part of the Crystal Spring Formation. The upper part was formed after silt and sand destroyed the algal mat, forming siltstone and sandstone. Laterally extensive diabase sills of molten rock later intruded above and below the carbonate rock layers; commercial grade talc was formed from thermal decay of carbonate rock at its contact with the lowest sill, which covers hundreds of square miles (many hundreds of km<sup>2</sup>). Today the formation is thick.

The Death Valley region once again rose above sea level, resulting in erosion. The Amargosa aulacogen then slowly sank beneath the seas; a sequence of carbonate banks that were topped by algal mats of stromatolites were laid on top of its eroded surface. Eventually these sediments and fossils became the Beck Spring Formation, which is thick.

Another round of uplift exposed the Beck Spring rocks and the underlying Crystal Spring to erosion; subsequent faster subsidence of the Amargosa aulacogen broke these formations into islands in later Proterozoic time. The resulting large sequence of thick conglomerate beds of pebbles and boulders in a sandy and muddy matrix that blanketed basins between higher areas is known as the Kingston Peak Formation. This formation is prominent near Wildrose, Harrisburg Flats, and Butte Valley and is thick.

Part of the Kingston Peak resembles glacial till by being poorly sorted and other parts have large boulder-sized dropstones resting in a fine-grained matrix of sandstone and siltstone. Similar deposits are found over North America during the same period, some 700 to 800 mya. Geologists therefore hypothesize that the world at that time was affected by a very severe glaciation, perhaps the most severe in geologic history (see Snowball Earth). The youngest rocks in the Pahrump Group are from basaltic lava flows.

Crustal thinning and rifting

thumb|Late Precambrian Noonday Formation scoured in Mosaic Canyon by episodic flow. (USGS photo)

A new rift opened that started to break apart the supercontinent Rodinia, of which North America was then a part. A shoreline similar to the present Atlantic Ocean margin of the United States, with coastal lowlands and a wide, shallow shelf but no volcanoes, lay to the east near where Las Vegas now resides. Good outcrops of these formations are exposed on the north face of Tucki Mountain in the northern Panamint Mountains.

The side road to Aguereberry Point successively traverses the shaly Johnnie Formation, the white Stirling Quartzite, and dark quartzites of the Wood Canyon Formation; at the Point itself is the great light-colored band of Zabriskie Quartzite dipping away toward Death Valley. Prominent outcrops are located between Death Valley Buttes and Daylight Pass, in upper Echo Canyon, and just west of Mare Spring in Titus Canyon. Before tilting to their present orientation, these four formations were a continuous pile of mud and sand deep that accumulated slowly on the nearshore ocean bottom. At the time, the Death Valley area was within ten or twenty degrees of the Paleozoic equator. Thousands of feet (hundreds of meters) of lavas erupted, pushing the ocean over to the west. A relatively featureless plain was formed from erosion over many millions of years. Deposition resumed some 35 Ma in the Oligocene epoch on a flood plain that developed in the area; sluggish streams migrated laterally over the surface, laying down cobbles, sand, and mud. Outcrops of the resulting conglomerates, sandstone, and mudstone of the Titus Canyon Formation can be observed in road cuts at Daylight Pass on Daylight Pass Road, which becomes State Route 374 a short distance from the pass. Several other similar formations were also laid down.

Large volcanic eruptions, originating near the Nevada Test Site, covered the Death Valley area and much of Nevada in thick sequences of silica-rich ash 27 million years ago. The ash has a rhyolitic composition, which is the volcanic equivalent of the plutonic rock granite; it covered what would later become the Grapevine Mountains in of ash. This ash filled in valleys and depressions; by 20 million years ago, the region from the Death Valley area across Nevada was a volcanic plain.

Extension produces the Basin and Range

thumb|Full extent of the Basin and Range. (NPS image)

Starting around 16 Ma in Miocene time and continuing into the present, a large part of the North American Plate in the region has been under extension by literally being pulled apart. Debate still surrounds the cause of this crustal stretching, but an increasingly popular idea among geologists called the slab gap hypothesis states that the spreading zone of the subducted Farallon Plate is pushing the continent apart. Whatever the cause, the result has been the formation of a large and still-growing region of relatively thin crust; the region grew an average of per year initially and then slowed to per year in the last 5 million years. Geologists call this region the Basin and Range Province.

Extensional forces causes rock at depth to stretch like silly putty and rock closer to the surface to break along normal faults into downfallen basins called grabens; small mountain ranges known as horsts run parallel to each other on either side of the graben. Normally the number of horsts and grabens is limited, but in the Basin and Range region there are dozens of horst/graben structures, each roughly north–south trending. A succession of these extend from immediately east of the Sierra Nevada, through almost all of Nevada, and into western Utah and southern Idaho. The crust in the Death Valley region between Lake Mead and the southern Sierra Nevada has been extended by as much as .

thumb|left|The deep Death Valley basin is filled with sediment (light yellow) eroded from the surrounding mountains. Black lines show some of the major faults that formed the valley. (USGS image)

The Furnace Creek Fault system, located in what is now the northern part of Death Valley, started to move about 14 Ma and the Southern Death Valley Fault system likely began to move by 12 million years ago. Both fault systems move with a right-lateral, or dextral, offset along strike-slip faults. With such faults, the opposite side of the fault appears to be moving right when facing the fault from either side. Both fault systems run parallel to and at the base of the ranges. Very often the same faults move laterally and vertically, simultaneously making them strike-slip and normal (i.e. oblique-slip). These two systems are also offset from each other; the area between the offset is thus put under enormous oblique tension, which intensifies subsidence there; Furnace Creek Basin opened in this area and the rest of Death Valley followed in stages. One of the last stages was the formation of Badwater Basin, which occurred by about 4 Ma. <!-- NEEDS CITE Torsional forces, probably associated with north-westerly movement of the Pacific Plate along the San Andreas Fault west of the region, is responsible for the lateral movement. Most of the vertical movement on normal faults in the valleys of the Death Valley area has manifested itself by the downward movement of their grabens. --> Data from gravimeters show that Death Valley's bedrock floor tilts down toward the east and is deepest under Badwater Basin; there is of fill under Badwater. By about 2 Ma Death Valley, Panamint Valley and their associated ranges were formed. (Tom Bean, NPS image)]]

thumb|left|[[Places of interest in the Death Valley area#Artist's Drive and Palette|Artist's Palette got its colors from volcanic deposits.]]

Igneous activity associated with the extension occurred from 12 to 4 Ma. Both intrusive (plutonic/solidified underground) and extrusive (volcanic/solidified above ground) igneous rocks were produced. Basaltic magma followed fault lines to the surface and erupted as cinder cones and lava flows. Some volcanic rocks were re-worked by hydrothermal systems to form colorful rocks and concentrated mineral formations, such as boron-rich minerals like borax; a Pliocene-aged example is the -thick Artist Drive Formation. Gold and silver ores were also concentrated by mineralizing fluids from igneous intrusions. Other times, heat from magma migrating close to the surface would superheat overlaying groundwater until it exploded, not unlike an exploding pressure-cooker, forming blowout craters and tuff rings. One example of such a feature is the roughly 2000-year-old and deep Ubehebe Crater (photo) in the northern part of the park; nearby smaller craters may be less than 200 to 300 years old.

Sediment filled the subsiding Furnace Creek Basin as the area was pulled apart by Basin and Range extension. The resulting -thick Furnace Creek Formation is made of lakebed sediments that consist of saline muds, gravels from nearby mountains and ash from the then-active Black Mountain volcanic field. Boron, which is abundant in this formation, is dissolved by ground water and flows out onto the northern end of the Death Valley playa. Today this formation is most-prominently exposed in the badlands at Zabriskie Point. Additional subsidence of the Furnace Creek Basin was filled by the four-million-year-old Funeral Formation, which consists of of conglomerates, sand, mud and volcanic material. Another smaller basin to the south was filled by the Copper Canyon Formation around the same time. Footprints and fossils of camels, horses, and mammoths are in all three of these Pliocene formations.

About 2–3 Ma, in the Pleistocene, continental ice sheets expanded from the polar regions of the globe to cover lower latitudes far north of the region, starting a series of cold glacial periods that were interrupted by warmer interglacial periods. These faults form part of a broader zone of faulting that extends between the eastern edge of the Sierra Nevada just across the border into Nevada, part of the southern Walker Lane (also described as the northern part of the Eastern California Shear Zone). The Walker Lane currently accommodates a significant part of the plate boundary motion between the Pacific Plate and the North American Plate and it has been proposed that this proportion will increase over time, with this zone eventually becoming the site of the plate boundary, accompanied by abandonment of the San Andreas Fault. However, there are currently no right-lateral strike-slip faults that pass through the Garlock Fault at the southern end of this zone, suggesting that this change will not occur for several millions of years at the earliest.

According to GPS data, the southern part of the Walker Lane accommodates 9–12&nbsp;mm per year of right lateral shear. Only about half of this amount can be explained by movement on the main fault zones, with the remainder being distributed on smaller, less well-defined structures. There have been no historical earthquakes in the Death Valley area, but major earthquakes have occurred on other faults within the southern Walker Lane, such as the M7.4 1872 Owens Valley earthquake on the Owens Valley Fault and the M7.1 mainshock of the 2019 Ridgecrest earthquakes, which was a result of movement on previously unmapped NW-SE trending right lateral strike-slip fault strands, close to the Little Lake and Airport Lake faults. Holocene ruptures have been identified on most of the major faults in the area.

Table of formations

This table of formations exposed in the Death Valley area lists and describes the exposed formations of the Death Valley National Park and the surrounding area.

{| class="wikitable"

|-

! System

! Series

! Formation

! Lithology and thickness

! Characteristic fossils

|-

| Quaternary

| Holocene

| &nbsp;

| Fan gravel; silt and salt on floor of playa, less than thick

| None

|-

| &nbsp;

| Pleistocene

| &nbsp;

| Fan gravel; silt and salt buried under floor of playa; perhaps thick

| &nbsp;

|-

| &nbsp;

| &nbsp;

| Funeral fanglomerate

| Cemented fan gravel with interbedded basaltic lavas, gravels cut by veins of calcite (Mexican onyx); perhaps thick

| Diatoms, pollen

|-

| Tertiary

| Pliocene

| Furnace Creek Formation

| Cemented gravel, silty and saliferous playa deposits; various salts, especially borates, more than thick

| Scarce

|-

| &nbsp;

| Miocene

| Artist Drive Formation

| Cemented gravel; playa deposits, much volcanic debris, perhaps thick

| Scarce

|-

| &nbsp;

| Oligocene

| Titus Canyon Formation

| Cemented gravel; mostly stream deposits; thick

| Vertebrates, titanotheres, etc.

|-

| &nbsp;

| Eocene and Paleocene

| &nbsp;

| Granitic intrusions and volcanics, not known to be represented by sedimentary deposits

| &nbsp;

|-

| Cretaceous and Jurassic

| &nbsp;

| Not represented, area was being eroded

| &nbsp;

| &nbsp;

|-

| Triassic

| &nbsp;

| Butte Valley Formation of Johnson (1957)

| Exposed in Butte Valley south of this area; of metasediments and volcanics

| Ammonites, smooth-shelled brachiopods, belemnites, and hexacorals

|-

| &nbsp;

| Pennsylvanian and Permian

| Formations at east foot of Tucki Mountain

| Conglomerate, limestone, and some shale. Conglomerate contains cobbles of limestone of Mississippian, Pennsylvanian, and Permian age. Limestone and shale contain spherical chert nodules. Abundant fusulinids. Thickness uncertain on account of faulting; estimate , top eroded.

| Beds with fusulinids, especially Fusulinella

|-

| Carboniferous

| Mississippian and Pennsylvanian

| Rest Spring Shale

| Mostly shale, some limestone, abundant spherical chert nodules. Thickness uncertain because of faulting; estimate .

| None

|-

| &nbsp;

| Mississippian

| Tin Mountain Limestone and younger limestone

| Mapped as 1 unit. Tin Mountain Limestone thick, is black with thin-bedded lower member and thick-bedded upper member. Unnamed limestone formation, thick, consists of interbedded chert and limestone in thin beds and in about equal proportions.

| Mixed brachiopods, corals, and crinoid stems. Syringopora (open-spaced colonies) Caninia cf. C. cornicula.

|-

| Devonian

| Middle and Upper Devonian

| Lost Burro Formation

| Limestone in light and dark beds thick give striped effect on mountainsides. Two quartzite beds, each about thick, near base, numerous sandstone beds above base. Top is well-bedded limestone and quartzite. Total thickness uncertain because of faulting; estimated .

| Brachiopods abundant, especially Spirifer, Cyrtospirifer, Productilla, Carmarotoechia, Atrypa. Stromatoporoids. Syringopora (closely spaced colonies).

|-

| Silurian and Devonian

| Silurian and Lower Devonian

| Hidden Valley Dolomite

| Thick-bedded, fine-grained, and even-grained dolomite, mostly light color. Thickness .

| Crinoid stems abundant, Including large types. Favosites.

|-

| Ordovician

| Upper Ordovician

| Ely Springs Dolomite

| Massive black dolomite, thick.

| Streptelasmatid corals: Grewingkia, Bighornia. Brachiopods.

|-

| &nbsp;

| Middle and Upper (?) Ordovician

| Eureka Quartzite

| Massive quartzite, with thin-bedded quartzite at base and top, thick.

| None

|-

| &nbsp;

| Lower and Middle Ordovician

| Pogonip Group

| Dolomite, with some limestone, at base, shale unit in middle, massive dolomite at top. Thickness, .

| Abundant large gastropods in massive dolomite at top: Palliseria and Maclurites, associated with Receptaculites. In lower beds: Protopliomerops, Kirkella, Orthid brachiopods.

|-

| Cambrian

| Upper Cambrian

| Nopah Formation

| Highly fossiliferous shale member thick at base, upper is dolomite in thick alternating black and light hands about thick. Total thickness of formation .

| In upper part, gastropods. In basal , trilobite trash beds containing Elburgis, Pseudagnostus, Horriagnostris, Elvinia, Apsotreta.

|-

| &nbsp;

| Middle and Upper Cambrian

| Bonanza King Formation

| Mostly thick-bedded arid massive dark-colored dolomite, thin-bedded limestone member thick below top of formation, 2 brown-weathering shaIy units, upper one fossiliferous, Total thickness Uncertain because of faulting; estimated about in Panamint Range, in Funeral Mountains.

| The only fossiliferous bed is shale below limestone member neat middle of formation. This shale contains linguloid brachiopods and trilobite trash beds with fragments of "Ehmaniella."

|-

| &nbsp;

| Lower and Middle Cambrian

| Carrara Formation

| An alternation of shaly and silty members with limestone members transitional between underlying clastic formations and overlying carbonate ones. Thickness about but variable because of shearing.

| Numerous trilobite trash beds in lower part yield fragments of olenellid trilobites.

|-

| &nbsp;

| Lower Cambrian

| Zabriskie Quartzite

| Quartzite, mostly massive arid granulated due to shearing, locally it) beds to thick. Thickness more than , variable because of shearing.

| No fossils

|-

| &nbsp;

| Lower Cambrian and Lower Cambrian (?)

| Wood Canyon Formation

| Basal unit is well-bedded quartzite above thick ' shaly Unit above this thick contains lowest olenellids in section; top unit of dolomite and quartzite thick.

| A few scattered olenellid trilobites and archaeocyathids in upper part of formation. Scolithus? tubes.

|-

| &nbsp;

| &nbsp;

| Stirling Quartzite

| Well-bedded quartzite in beds thick comprising thick members of quartzite thick separated by of purple shale, crossbedding conspicuous in quartzite. Maximum thickness about .

| None

|-

| &nbsp;

| &nbsp;

| Johnnie Formation

| Mostly shale, in part olive brown, in part purple. Basal member thick is interbedded dolomite arid quartzite with pebble conglomerate. Locally, fair dolomite near middle arid at top. Thickness more than .

| None

|-

| Precambrian

| &nbsp;

| Noonday Dolomite

| In southern Panamint Range, dolomite in Indistinct beds; lower part cream colored, upper part gray. Thickness . Farther north, where mapped as Noonday(?) Dolomite, contains much limestone, tan and white, and some limestone conglomerate. Thickness about .

| Scolithus? tubes

|-

| &nbsp;

| &nbsp;

| Unconformity

| &nbsp;

| &nbsp;

|-

| &nbsp;

| &nbsp;

| Kingston Peak(?) Formation

| Mostly diamictite, sandstone, and shale; some limestone arid dolomite olistoliths near middle. At least thick. Although tentatively assigned to Kingston Peak Formation, similar rocks along west side of Panamint Range have been identified as Kingston Peak.

| None.

|-

| &nbsp;

| &nbsp;

| Beck Spring Dolomite

| Not mapped; outcrops are to the west. Blue-gray cherry dolomite, thickness estimated about Identification uncertain.

| None

|-

| &nbsp;

| Pahrump Series

| Crystal Spring Formation

| Recognized only in Galena Canyon and south. Total thickness about . Consists of basal conglomerate overlain by quartzite that grades upward into purple shale arid thinly bedded dolomite, upper part, thick bedded dolomite, diabase, and chert. Talc deposits where diabase intrudes dolomite.

| None

|-

| &nbsp;

| &nbsp;

| Unconformity

| &nbsp;

| &nbsp;

|-

| &nbsp;

| &nbsp;

| Rocks of the crystalline basement

| Metasedimentary rocks with granitic intrusions

| None

|}

Table of salts

thumb|This false-color radar image shows central Death Valley and the different surface types in the area. Radar is sensitive to surface roughness with rough areas showing up brighter than smooth areas, which appear dark. This is seen in the contrast between the bright mountains that surround the dark, smooth basins and valleys of Death Valley. The image shows Furnace Creek [[alluvial fan (green crescent feature) at the far right, and the sand dunes near Stove Pipe Wells at the center. (NASA image)]]

{| class="wikitable"

|-

|+Table of salts found in Death Valley

|-

! Mineral

! Composition

! Known or probable occurrence

|-

| Halite

| NaCl

| Principal constituent of chloride zone and of salt-impregnated sulfate and carbonate deposits.

|-

| Sylvite

| KCl

| With halite.

|-

| Trona

| Na<sub>3</sub>H(CO<sub>3</sub>)<sub>2</sub>2H<sub>2</sub>O

| Carbonate zone of Cottonball Basin, especially in marshes.

|-

| Thermonatrite

| Na<sub>2</sub>CO<sub>3</sub>·H<sub>2</sub>O

| Questionably present on floodplain in Badwater Basin, would be expected in marshes of carbonate zone in Cottonball Basin.

|-

| Gaylussite

| Na<sub>2</sub>Ca(CO<sub>3</sub>)2·5H<sub>2</sub>O

| Carbonate zone and floodplain in Badwater Basin.

|-

| Calcite

| CaCO<sub>3</sub>

| Occurs as clastic grains in sediments underlying salt pan and as sharply terminated crystals in clay fraction of carbonate zone and in sediments underlying sulfate zone.

|-

| Magnesite

| MgCO<sub>3</sub>

| Obtained in artificially evaporated brines from Death Valley; not yet identified in salt pan; may be expected in carbonate zone of Cottonball Basin.

|-

| Dolomite

| CaMg(CO<sub>3</sub>)2

| identified only as a detrital mineral; may be expected in carbonate zone.

|-

| Northupite and/or tychite

| Na<sub>3</sub>MgCl(CO<sub>3</sub>) and/or Na<sub>6</sub>Mg<sub>2</sub>(SO<sub>4</sub>)·(CO<sub>3</sub>)<sub>4</sub>

| An isotropic mineral, having index of refraction in the range of Northupite and Tychite, has been observed in saline facies of sulfate zone in Cottonball Basin.

|-

| Burkeite

| Na<sub>6</sub>(CO<sub>3</sub>)(SO<sub>4</sub>)<sub>2</sub>

| Sulfate zone in Cottonball Basin.

|-

| Thenardite

| Na<sub>2</sub>SO<sub>4</sub>

| Common in all zones in Cottonball Basin and in sulfate marshes in Middle and Badwater basins.

|-

| Mirabilite

| Na<sub>2</sub>SO<sub>4</sub>·10H<sub>2</sub>O

| Occurs on floodplains in Cottonball Basin immediately following winter storms.

|-

| Glauberite

| Na<sub>2</sub>Ca(SO<sub>4</sub>)<sub>2</sub>

| Common on floodplains except in central part of Badwater Basin; sulfate zone in Cottonball Basin.

|-

| Anhydrite

| CaSO<sub>4</sub>

| As layer capping massive gypsum 1 mile (2&nbsp;km) north of Badwater. Possibly also as dry-period efflorescence on floodplains.

|-

| Bassanite

| 2CaSO<sub>4</sub>·H<sub>2</sub>O

| As layer capping massive gypsum along west side of Badwater Basin and as dry-period efflorescence in floodplains.

|-

| Gypsum

| CaSO<sub>4</sub>·2H<sub>2</sub>O

| In sulfate caliche, layer in carbonate zone, particularly in Middle and Badwater basins, in sulfate marshes and as massive deposits in sulfate zone.

|-

| Bloedite

| Na<sub>2</sub>Mg(SO<sub>4</sub>)<sub>2</sub>·4H<sub>2</sub>O

| Questionably present in efflorescence on floodplain in chloride zone.

|-

| Polyhalite

| K<sub>2</sub>Ca2Mg(SO<sub>4</sub>)<sub>4</sub>·2H<sub>2</sub>O

| Questionably present on floodplain in chloride zone.

|-

| Celestine

| SrSO<sub>4</sub>

| Found with massive gypsum.

|-

| Kernite

| Na<sub>2</sub>B<sub>4</sub>O<sub>7</sub>·4H<sub>2</sub>O

| Possibly present in Middle Basin in surface layer of layered sulfate and chloride salts.

|-

| Tincalconite

| Na<sub>2</sub>B<sub>4</sub>O<sub>7</sub>·5H<sub>2</sub>O

| Probably occurs as dehydration product of borax.

|-

| Borax

| Na<sub>2</sub>B<sub>4</sub>O<sub>7</sub>·10H<sub>2</sub>O

| Floodplains and marshes in Cottonball Basin.

|-

| Inyoite

| Ca<sub>2</sub>B<sub>6</sub>O<sub>11</sub>·13H<sub>2</sub>O

| Questionably present (X-ray determination but unsatisfactory) in floodplain in Badwater Basin.

|-

| Meyerhofferite

| Ca<sub>2</sub>B<sub>6</sub>O<sub>11</sub>·7H<sub>2</sub>O

| Found in all zones in Badwater Basin and in rough silty rock salt in Cottonball Basin

|-

| Colemanite

| Ca<sub>2</sub>B<sub>6</sub>O<sub>11</sub>·5H<sub>2</sub>O

| Questionably present (X-ray determination but unsatisfactory) in floodplain in Badwater Basin.

|-

| Ulexite

| NaCaB<sub>5</sub>O<sub>9</sub>·8H<sub>2</sub>O

| Common in floodplain in Cottonball Basin; known as "cottonball"

|-

| Proberite

| NaCaB<sub>5</sub>O<sub>9</sub>·5H<sub>2</sub>O

| A fibrous borate with index of refraction higher than ulexite occurs on dry areas in Cottonball Basin following hot dry spells and in surface layer of smooth silty rock salt.

|-

| Soda niter

| NaNO<sub>3</sub>

| Weak, but positive chemical tests obtained locally.

|}

See also

  • Places of interest in the Death Valley area
  • Category: Death Valley
  • Category: Geology of California

References

Bibliography

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  • Proceedings on Conference on Status of Geologic Research and Mapping, Death Valley National Park
  • Tertiary Extensional Features, Death Valley, Eastern California
  • Detailed USGS geological map of the Death Valley area
  • Key for the geological units on the USGS map