The Delaware Basin is a geologic
depositional and
structural basin
A structural basin is a large-scale structural formation of rock strata formed by tectonic warping of previously flat-lying strata. They are geological depressions, the inverse of domes. Elongated structural basins are also known as synclines. ...
in
West Texas
West Texas is a loosely defined region in the U.S. state of Texas, generally encompassing the arid and semiarid lands west of a line drawn between the cities of Wichita Falls, Abilene, and Del Rio.
No consensus exists on the boundary betwee ...
and southern
New Mexico
)
, population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano)
, seat = Santa Fe
, LargestCity = Albuquerque
, LargestMetro = Tiguex
, OfficialLang = None
, Languages = English, Spanish ( New Mexican), Navajo, Ker ...
, famous for holding large oil fields and for a fossilized reef exposed at the surface.
Guadalupe Mountains National Park
Guadalupe Mountains National Park is an American national park in the Guadalupe Mountains, east of El Paso, Texas. The mountain range includes Guadalupe Peak, the highest point in Texas at , and El Capitan used as a landmark by travelers on the ro ...
and
Carlsbad Caverns National Park
Carlsbad Caverns National Park is an American national park in the Guadalupe Mountains of southeastern New Mexico. The primary attraction of the park is the show cave Carlsbad Cavern. Visitors to the cave can hike in on their own via the natura ...
protect part of the basin. It is part of the larger
Permian Basin, itself contained within the
Mid-Continent oil province
The Mid-continent oil field is a broad area containing hundreds of oil fields in Arkansas, Kansas, Louisiana, New Mexico, Oklahoma and Texas. The area, which consists of various geological strata and diverse trap types, was discovered and e ...
.
Geology
By earliest
Permian
The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleoz ...
time, during the
Wolfcampian
The Cisuralian is the first Series (stratigraphy), series/Epoch (geology), epoch of the Permian. The Cisuralian was preceded by the Pennsylvanian (geology), Pennsylvanian and followed by the Guadalupian. The Cisuralian Epoch is named after the w ...
Epoch
In chronology and periodization, an epoch or reference epoch is an instant in time chosen as the origin of a particular calendar era. The "epoch" serves as a reference point from which time is measured.
The moment of epoch is usually decided by ...
, the ovoid shaped subsiding Delaware Basin extended over 10,000 square miles (26,000 km²) in what is now western
Texas
Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...
and southeast
New Mexico
)
, population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano)
, seat = Santa Fe
, LargestCity = Albuquerque
, LargestMetro = Tiguex
, OfficialLang = None
, Languages = English, Spanish ( New Mexican), Navajo, Ker ...
.
[.] This period of deposition left a thickness of 1600 to 2200 feet (490 to 670 m) of
limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...
interbedded with dark-colored
shale
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especial ...
.
A narrow outlet that geologists call the ''Hovey Channel'' periodically supplied new
seawater
Seawater, or salt water, is water from a sea or ocean. On average, seawater in the world's oceans has a salinity of about 3.5% (35 g/L, 35 ppt, 600 mM). This means that every kilogram (roughly one liter by volume) of seawater has appro ...
from the
Panthalassa Ocean to the west. The somewhat smaller and shallower
Midland Basin was just east and the much smaller
Marfa Basin was to the southwest. All three basins were south of the
equator
The equator is a circle of latitude, about in circumference, that divides Earth into the Northern and Southern hemispheres. It is an imaginary line located at 0 degrees latitude, halfway between the North and South poles. The term can als ...
, north of the
Ouachita Mountains
The Ouachita Mountains (), simply referred to as the Ouachitas, are a mountain range in western Arkansas and southeastern Oklahoma. They are formed by a thick succession of highly deformed Paleozoic strata constituting the Ouachita Fold and Thru ...
of mid-Texas, and part of the northern continent
Laurasia
Laurasia () was the more northern of two large landmasses that formed part of the Pangaea supercontinent from around ( Mya), the other being Gondwana. It separated from Gondwana (beginning in the late Triassic period) during the breakup of Pan ...
. Structurally the Delaware, Midland and Marfa were foreland basins created when the
Ouachita Mountains
The Ouachita Mountains (), simply referred to as the Ouachitas, are a mountain range in western Arkansas and southeastern Oklahoma. They are formed by a thick succession of highly deformed Paleozoic strata constituting the Ouachita Fold and Thru ...
were uplifted as the southern continent
Gondwana
Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages ...
collided with Laurasia, forming the supercontinent
Pangea
Pangaea or Pangea () was a supercontinent that existed during the late Paleozoic and early Mesozoic eras. It assembled from the earlier continental units of Gondwana, Euramerica and Siberia during the Carboniferous approximately 335 million y ...
in the Late
Carboniferous
The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carbonifero ...
(
Pennsylvanian). The Ouachita Mountains formed a
rainshadow
A rain shadow is an area of significantly reduced rainfall behind a mountainous region, on the side facing away from prevailing winds, known as its leeward side.
Evaporated moisture from water bodies (such as oceans and large lakes) is carri ...
over the basins, and a warm shallow sea flooded the surrounding area. On the other side of the equator, the
Ancestral Rocky Mountains
The geology of the Rocky Mountains is that of a discontinuous series of mountain ranges with distinct geological origins. Collectively these make up the Rocky Mountains, a mountain system that stretches from Northern British Columbia through cen ...
formed a large mountainous
island
An island (or isle) is an isolated piece of habitat that is surrounded by a dramatically different habitat, such as water. Very small islands such as emergent land features on atolls can be called islets, skerries, cays or keys. An island ...
.
The Delaware Basin temporarily stopped subsiding in the
Leonardian
In the geologic timescale, the Kungurian is an age or stage of the Permian. It is the latest or upper of four subdivisions of the Cisuralian Epoch or Series. The Kungurian lasted between and million years ago (Ma). It was preceded by the Artin ...
Epoch at the start of the mid-
Permian
The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleoz ...
. Small banks along its margin developed along with small discontinuous patch
reef
A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock out ...
s in the shallow water just offshore. The first
formation
Formation may refer to:
Linguistics
* Back-formation, the process of creating a new lexeme by removing or affixes
* Word formation, the creation of a new word by adding affixes
Mathematics and science
* Cave formation or speleothem, a secondar ...
that resulted was the
Yeso and consists of alternating beds of
dolomitic
Dolomite () is an anhydrous carbonate mineral composed of calcium magnesium carbonate, ideally The term is also used for a sedimentary carbonate rock composed mostly of the mineral dolomite. An alternative name sometimes used for the dolomiti ...
limestone,
gypsum
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywall. ...
, and
sandstone
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks.
Most sandstone is composed of quartz or feldspar (both silicates) ...
. The sediments responsible for creating the Yeso were deposited in nearshore areas that graded into the carbonate banks of the
Victorio Peak Formation
The Victorio Peak Formation is a geologic formation found in the Delaware Basin in Texas and New Mexico. It preserves fossils dating back to the Leonardian Age of the Permian Period.Kues and Giles 2004
Description
The formation consists of ligh ...
in the deeper waters. Thin-bedded limestones of the
Bone Spring Formation accumulated as limy ooze in the stagnant deepest part of the basin.
Subsidence of the Delaware Basin restarted later in the mid Permian and by the
Guadalupian
The Guadalupian is the second and middle series/epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico and Texas, and dates between 272.95 ± 0. ...
Epoch of the upper Permian the patch reefs had grown larger. Sediments deposited close to the shore are now the
chert
Chert () is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a prec ...
y dolomites of the
San Andres Formation while deposition a little further out forms the
quartz
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical form ...
sandstone and scattered patch reefs of the
Brushy Canyon Formation.
Rapid subsidence of the basin started in the middle Guadalupian. Patch reefs responded by rapid (mostly vertical) growth, resulting in the Goat Seep Reef. Three
facies
In geology, a facies ( , ; same pronunciation and spelling in the plural) is a body of rock with specified characteristics, which can be any observable attribute of rocks (such as their overall appearance, composition, or condition of formatio ...
developed:
*
Sediment
Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand an ...
s deposited in a
lagoon
A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into ''coastal lagoons'' (or ''barrier lagoons'') a ...
, forming the sandstones and dolomites of the
Queen
Queen or QUEEN may refer to:
Monarchy
* Queen regnant, a female monarch of a Kingdom
** List of queens regnant
* Queen consort, the wife of a reigning king
* Queen dowager, the widow of a king
* Queen mother, a queen dowager who is the mother ...
and
Grayburg Formations.
*
Sponge
Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through t ...
and
algae
Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...
skeleton
A skeleton is the structural frame that supports the body of an animal. There are several types of skeletons, including the exoskeleton, which is the stable outer shell of an organism, the endoskeleton, which forms the support structure inside ...
s accumulated near the
Goat Seep Reef to become the Getaway Bank.
* Quartz
sand
Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of s ...
laid down further in the basin became the
Cherry Canyon Formation
The Cherry Canyon Formation is a geologic formation found in the Delaware Basin of southeastern New Mexico and western Texas. It contains fossils characteristic of the Guadalupian Age of the Permian Period.Kues and Giles 2004, p.100
Description
...
.
Subsidence of the basin stopped for good by the later part of the Guadalupian. Capitan Reef was the largest in the basin, and it rapidly grew 350 miles (560 km) around it. The facies were:
* Fine-grained sand and
carbonate
A carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word ''carbonate'' may also refer to a carbonate ester, an organic compound containing the carbonate g ...
s deposited near the shore became the dolomites and sandstone of the
Artesia Group.
* Offshore accumulations of sand and limey ooze in the basin were lithified into sandstone and limestone belonging to the
Bell Canyon Formation
The Bell Canyon Formation is a geologic formation found in the Delaware Basin of southeastern New Mexico and western Texas. It contains fossils characteristic of the Guadalupian Age of the Permian Period.
Description
The formation consists most ...
.
* The
Capitan Formation
The Capitan Formation is a geologic formation found in western Texas and southeastern New Mexico. It is a fossilized reef dating to the Guadalupian Age of the Permian period.
The formation underlies El Capitan in Guadalupe Mountains National Park ...
consists of Capitan Reef and is made of reef limestone.
Capitan Reef was built primarily from calcareous sponges, encrusting algae such as
stromatolite
Stromatolites () or stromatoliths () are layered sedimentary formations (microbialite) that are created mainly by photosynthetic microorganisms such as cyanobacteria, sulfate-reducing bacteria, and Pseudomonadota (formerly proteobacteria). The ...
s, and directly from seawater as a limey mud. In stark contrast,
Cenozoic
The Cenozoic ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterised by the dominance of mammals, birds and flowering plants, a cooling and drying climate, and the current configura ...
(current era),
Mesozoic
The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceo ...
(age of the
dinosaur
Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...
s), and even middle
Paleozoic
The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon.
The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838
by combining the Greek words ''palaiós'' (, "old") and ' ...
(well before the Permian) reefs are mainly composed of
coral
Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and sec ...
s.
Sea level
Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardised g ...
dropped as the late
Permian glaciation intensified and locked increasing amounts of water in distant
ice cap
In glaciology, an ice cap is a mass of ice that covers less than of land area (usually covering a highland area). Larger ice masses covering more than are termed ice sheets.
Description
Ice caps are not constrained by topographical features ...
s. Sedimentation continued to fill the Delaware Basin into the
Ochoan Epoch of the upper Permian, periodically cutting the basin off from its source of seawater. Part of the resulting
brine
Brine is a high-concentration solution of salt (NaCl) in water (H2O). In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of solutions used for br ...
became the deep-water
evaporite
An evaporite () is a water-soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as ocea ...
s of the
Castile Formation. The Castile consists of 1/16 inch (1.6 mm) thick laminae of alternating gray
anhydrite
Anhydrite, or anhydrous calcium sulfate, is a mineral with the chemical formula CaSO4. It is in the orthorhombic crystal system, with three directions of perfect cleavage parallel to the three planes of symmetry. It is not isomorphous with the ...
and
gypsum
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywall. ...
, brown
calcite
Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on ...
, and
halite
Halite (), commonly known as rock salt, is a type of salt, the mineral (natural) form of sodium chloride ( Na Cl). Halite forms isometric crystals. The mineral is typically colorless or white, but may also be light blue, dark blue, purple, p ...
. As the salt concentration increased, halite and
potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosphe ...
-rich
salt
Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantitie ...
precipitated from the briny body of water on its margin and on nearshore areas. This salt layer covered an increasingly large area as the water level dropped, forming the
Salado Formation
The Salado Formation is a geologic formation in west Texas and southeastern New Mexico. It was deposited in the Ochoan Stage of the Permian period.
Description
The formation consists of up to of halite with significant anhydrite, red beds, and p ...
.
The Delaware Basin was filled at least to the top of Capitan Reef and mostly covered by dry land before the end of the
Ochoan
The Ochoan is a stage in the Permian stratigraphy (and an age in the geologic timescale) of North America. The Ochoan age is roughly simultaneous with the Changhsingian age in the timescale of the ICS. This post-Guadalupian stage is known for h ...
Epoch. Rivers migrated over its surface and deposited the red silt and sand that now constitute the
siltstone
Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, p ...
and sandstone of the
Rustler and
Dewey Lake Formations.
A
karst topography
Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant ro ...
developed as
groundwater
Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolidate ...
circulated in the buried limestone formations, dissolving away caverns which were later destroyed by infill and erosion.
Uplift associated with the
Laramide orogeny
The Laramide orogeny was a time period of mountain building in western North America, which started in the Late Cretaceous, 70 to 80 million years ago, and ended 35 to 55 million years ago. The exact duration and ages of beginning and end of the o ...
in the late
Mesozoic
The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceo ...
and early
Cenozoic
The Cenozoic ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterised by the dominance of mammals, birds and flowering plants, a cooling and drying climate, and the current configura ...
created a major
fault along which the
Guadalupe Mountains
The Guadalupe Mountains ( es, Sierra de Guadalupe) are a mountain range located in West Texas and southeastern New Mexico. The range includes the highest summit in Texas, Guadalupe Peak, , and the "signature peak" of West Texas, El Capitan, both ...
were thrust into existence. The range forms the tilted upthrown part of the system and the Salt Flat Bolson forms the downfallen block.
Capitan Reef limestone was exposed above the surface with the 1000-foot-high (300 m)
El Capitan being its most prominent feature. Other large outcrops compose the
Apache Mountains and
Glass Mountains
The Glass Mountains (also known as Gloss Mountains or Gloss Hills) are not actually mountains, but a series of mesas and buttes that are part of the Blaine Escarpment that extends from the Permian red beds of northwestern Oklahoma in Major Co ...
to the south.
[''Geology of National Parks'', p. 189, "Geologic Features"]
Stream
A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a stream ...
s eroded the softer sediment away, lowering the ground level to its current position. Acidic
groundwater
Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolidate ...
excavated
cave
A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word ''cave'' can refer to smaller openings such as sea ...
s in the limestone of the higher areas and eroded sediment helped fill any remaining Permian-aged caves. Unlike most other caves in limestone, in this case the
acid
In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...
was likely derived from
hydrogen sulfide
Hydrogen sulfide is a chemical compound with the formula . It is a colorless chalcogen-hydride gas, and is poisonous, corrosive, and flammable, with trace amounts in ambient atmosphere having a characteristic foul odor of rotten eggs. The unde ...
and
sulfide
Sulfide (British English also sulphide) is an inorganic anion of sulfur with the chemical formula S2− or a compound containing one or more S2− ions. Solutions of sulfide salts are corrosive. ''Sulfide'' also refers to chemical compounds lar ...
-rich brines that were freed by tectonic activity in the mid-
Tertiary
Tertiary ( ) is a widely used but obsolete term for the geologic period from 66 million to 2.6 million years ago.
The period began with the demise of the non-avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start ...
and mixed with
oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...
ated groundwater, forming
sulfuric acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formu ...
.
Carlsbad Cavern
Carlsbad Caverns National Park is an American national park in the Guadalupe Mountains of southeastern New Mexico. The primary attraction of the park is the show cave Carlsbad Cavern. Visitors to the cave can hike in on their own via the natur ...
s and nearby modern caves started to form at this time in the
groundwater
Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolidate ...
-saturated
phreatic zone
The phreatic zone, saturated zone, or zone of saturation, is the part of an aquifer, below the water table, in which relatively all pores and fractures are saturated with water. Above the water table is the unsaturated or vadose zone.
The phre ...
. Due to the semiarid
climate
Climate is the long-term weather pattern in an area, typically averaged over 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the meteorologic ...
, the karst topography that was created lacks the characteristic depressions,
sink hole
A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as ''vrtače'' and shakeholes, and to openi ...
s, pits, and solutional fissures on the surface.
Mass wasting
Mass wasting, also known as mass movement, is a general term for the movement of rock or soil down slopes under the force of gravity. It differs from other processes of erosion in that the debris transported by mass wasting is not entrained in ...
such as
landslide
Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated grade (slope), slope failures, mudflows, and debris flows. Landslides occur in a variety of ...
s further reduced topographic relief.
Additional uplift of the Guadalupe Mountains in the
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58[Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...](_blank)
epochs enlarged Carlsbad Cavern and nearby caves. Parts of the major caves emerged from the saturated phreatic zone into the
vadose
The vadose zone, also termed the unsaturated zone, is the part of Earth between the land surface and the top of the phreatic zone, the position at which the groundwater (the water in the soil's pores) is at atmospheric pressure ("vadose" is fr ...
with temporary periods of repose during which additional
solution
Solution may refer to:
* Solution (chemistry), a mixture where one substance is dissolved in another
* Solution (equation), in mathematics
** Numerical solution, in numerical analysis, approximate solutions within specified error bounds
* Soluti ...
al excavation occurred in the phreatic zone. These pauses in emergence are thought to be responsible for creating the different levels in Carlsbad Caverns. Precipitation of
carbon dioxide
Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...
-rich water that infiltrated into the cavern created
speleothem
A speleothem (; ) is a geological formation by mineral deposits that accumulate over time in natural caves. Speleothems most commonly form in calcareous caves due to carbonate dissolution reactions. They can take a variety of forms, depending on ...
s, especially in the
humid parts of the Pleistocene. Speleothems found in the "Big Room" of Carlsbad were dated using electron spin resonance dating and were found to be 500,000 to 600,000 years old. This indicates that the Big Room level was dry by that time.
The soft and easily eroded gypsum of the Castile Formation was removed, exposing the Guadalupe Escarpment.
Additional erosion intersected the upper part of Carlsbad Cavern and other caves, forming their entrances. Drying of cave air has reduced the growth rate of speleothems and encouraged the development of nodular
travertine
Travertine ( ) is a form of terrestrial limestone deposited around mineral springs, especially hot springs. It often has a fibrous or concentric appearance and exists in white, tan, cream-colored, and even rusty varieties. It is formed by a pro ...
("cave popcorn").
See also
*
List of geographical regions in Texas
Texas is the second-largest state in the United States, with an area of and a population of 29.14 million in 254 counties. This covers an area wide by long. Due to its location and size, it is a part of a large number of unique geological reg ...
*
El Capitan (Texas)
El Capitan ( es, El Capitán) is a peak in Culberson County, Texas, located within Guadalupe Mountains National Park. The 10th-highest peak in Texas at 8,085 ft (2,464 m), El Capitan is part of the Guadalupe Mountains, an exposed portion of ...
*
McKittrick Canyon
McKittrick Canyon is a scenic canyon within the Guadalupe Mountains of West Texas and Eddy County, New Mexico. The steep, towering walls of McKittrick Canyon protect a rich riparian oasis in the midst of the Chihuahuan Desert.
The majority of M ...
*
Chihuahuan Desert
The Chihuahuan Desert ( es, Desierto de Chihuahua, ) is a desert ecoregion designation covering parts of northern Mexico and the southwestern United States. It occupies much of far West Texas, the middle to lower Rio Grande Valley and the lower P ...
*
West Texas
West Texas is a loosely defined region in the U.S. state of Texas, generally encompassing the arid and semiarid lands west of a line drawn between the cities of Wichita Falls, Abilene, and Del Rio.
No consensus exists on the boundary betwee ...
References
* ''Earth System History'', Steven M. Stanley, (W.H. Freeman and Company; 1999)
* ''Geology of National Parks: Fifth Edition'', Ann G. Harris, Esther Tuttle, Sherwood D., Tuttle (Iowa, Kendall/Hunt Publishing; 1997)
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{{New Mexico
Geology of New Mexico
Geologic provinces of Texas
Sedimentary basins of North America
Structural basins of the United States
Oil fields of the United States
Permian geology of New Mexico
Permian geology of Texas