Quartz Mountain
Encyclopedia
Quartz Mountain is located in southwest Oklahoma. It is the namesake of Quartz Mountain Nature Park
and its eastern flank is encolosed by the park boundaries. The park is open to the public year round for rock climbing, hiking, boating, camping, nature observation and photography, and environmental education and interpretation. The mountain overlooks scenic Lake Altus.
. In simplest terms, the Wichita Mountains are rocky promontories and rounded hills made of red and black igneous rocks, light-colored sedimentary rocks, and boulder conglomerates. The Wichita Mountains were formed in four distinct geologic episodes. 1.) Magmatism induced by continental rifting just prior to and in the Cambrian
Period produced the granites
and rhyolites
(the red rocks), gabbroic rocks
, anorthosites
, and diabases
(the black rocks). 2.) Subsidence resulted in burial by sandstones
and carbonates
(the light-colored rocks) during the early Paleozoic
. 3.) Uplift during the Pennsylvanian
Ouachita Orogeny
brought these rocks to the surface as mountains. 4.) Weathering and erosion
during the Permian
Period flattened the mountains and produced a mantle of conglomerates
. The mountains themselves are Permian
landforms covered and preserved by river-borne sediments in the Permian
and partially excavated only in recent geological times. Exposure of these fossil mountains is greatest towards the southeast; much of the western part of the Permian
range remains buried under sandstones
and shales
.
Quartz Mountain is made of granite
emplaced during the early Cambrian
period. Like the other granite knobs nearby, and the larger masses of granite in the eastern Wichita Mountains, theses rocks are part of the Wichita Granite Group . Most of Quartz Mountain and the other exposures in the park are homogenous pink-red Lugert granite. However, the flank of Quartz Mountain, as well as the adjacent peaks to the west are made of a corser grained, red Reformatory Granite. The Reformatory Granite is quarried locally in and around the appropriately named town of Granite; the park's numerous monuments are polished monoliths of the quarry products. A mixed zone between the two units reveals that these are two separate pulses of magma intruding the same level of the crust, and that the Lugert post-dates the intrusion of the Reformatory. Numerous miarolitic cavities and hydrothermal veins pervade this zone and its surroundings. Both contain appreciable amounts of quartz
.
Quartz Mountain Nature Park
Quartz Mountain Nature Park is located in southwest Oklahoma at the western end of the Wichita Mountains. It is operated by Oklahoma State Regents for Higher Education. Much of the area was formerly Quartz Mountain State Park, one of the original seven Oklahoma State Parks designated in 1935...
and its eastern flank is encolosed by the park boundaries. The park is open to the public year round for rock climbing, hiking, boating, camping, nature observation and photography, and environmental education and interpretation. The mountain overlooks scenic Lake Altus.
Geology
Quartz Mountain is one of the westernmost peaks in the Wichita MountainsWichita Mountains
The Wichita Mountains are located in the southwestern portion of the U.S. state of Oklahoma. The mountains are a northwest-southeast trending series of rocky promontories, many capped by 540 million-year old granite. These were exposed and rounded by weathering during the Permian Period...
. In simplest terms, the Wichita Mountains are rocky promontories and rounded hills made of red and black igneous rocks, light-colored sedimentary rocks, and boulder conglomerates. The Wichita Mountains were formed in four distinct geologic episodes. 1.) Magmatism induced by continental rifting just prior to and in the Cambrian
Cambrian
The Cambrian is the first geological period of the Paleozoic Era, lasting from Mya ; it is succeeded by the Ordovician. Its subdivisions, and indeed its base, are somewhat in flux. The period was established by Adam Sedgwick, who named it after Cambria, the Latin name for Wales, where Britain's...
Period produced the granites
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...
and rhyolites
Rhyolite
This page is about a volcanic rock. For the ghost town see Rhyolite, Nevada, and for the satellite system, see Rhyolite/Aquacade.Rhyolite is an igneous, volcanic rock, of felsic composition . It may have any texture from glassy to aphanitic to porphyritic...
(the red rocks), gabbroic rocks
Gabbro
Gabbro refers to a large group of dark, coarse-grained, intrusive mafic igneous rocks chemically equivalent to basalt. The rocks are plutonic, formed when molten magma is trapped beneath the Earth's surface and cools into a crystalline mass....
, anorthosites
Anorthosite
Anorthosite is a phaneritic, intrusive igneous rock characterized by a predominance of plagioclase feldspar , and a minimal mafic component...
, and diabases
Diabase
Diabase or dolerite is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. In North American usage, the term diabase refers to the fresh rock, whilst elsewhere the term dolerite is used for the fresh rock and diabase refers to altered material...
(the black rocks). 2.) Subsidence resulted in burial by sandstones
Sandstone
Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...
and carbonates
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
(the light-colored rocks) during the early Paleozoic
Paleozoic
The Paleozoic era is the earliest of three geologic eras of the Phanerozoic eon, spanning from roughly...
. 3.) Uplift during the Pennsylvanian
Pennsylvanian
The Pennsylvanian is, in the ICS geologic timescale, the younger of two subperiods of the Carboniferous Period. It lasted from roughly . As with most other geochronologic units, the rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain...
Ouachita Orogeny
Ouachita orogeny
The Ouachita orogeny was a mountain building event that resulted in the folding and faulting of strata currently exposed in the Ouachita Mountains...
brought these rocks to the surface as mountains. 4.) Weathering and erosion
Erosion
Erosion is when materials are removed from the surface and changed into something else. It only works by hydraulic actions and transport of solids in the natural environment, and leads to the deposition of these materials elsewhere...
during the Permian
Permian
The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...
Period flattened the mountains and produced a mantle of conglomerates
Conglomerate (geology)
A conglomerate is a rock consisting of individual clasts within a finer-grained matrix that have become cemented together. Conglomerates are sedimentary rocks consisting of rounded fragments and are thus differentiated from breccias, which consist of angular clasts...
. The mountains themselves are Permian
Permian
The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...
landforms covered and preserved by river-borne sediments in the Permian
Permian
The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...
and partially excavated only in recent geological times. Exposure of these fossil mountains is greatest towards the southeast; much of the western part of the Permian
Permian
The PermianThe term "Permian" was introduced into geology in 1841 by Sir Sir R. I. Murchison, president of the Geological Society of London, who identified typical strata in extensive Russian explorations undertaken with Edouard de Verneuil; Murchison asserted in 1841 that he named his "Permian...
range remains buried under sandstones
Sandstone
Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...
and shales
Shale
Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...
.
Quartz Mountain is made of granite
Granite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...
emplaced during the early Cambrian
Cambrian
The Cambrian is the first geological period of the Paleozoic Era, lasting from Mya ; it is succeeded by the Ordovician. Its subdivisions, and indeed its base, are somewhat in flux. The period was established by Adam Sedgwick, who named it after Cambria, the Latin name for Wales, where Britain's...
period. Like the other granite knobs nearby, and the larger masses of granite in the eastern Wichita Mountains, theses rocks are part of the Wichita Granite Group . Most of Quartz Mountain and the other exposures in the park are homogenous pink-red Lugert granite. However, the flank of Quartz Mountain, as well as the adjacent peaks to the west are made of a corser grained, red Reformatory Granite. The Reformatory Granite is quarried locally in and around the appropriately named town of Granite; the park's numerous monuments are polished monoliths of the quarry products. A mixed zone between the two units reveals that these are two separate pulses of magma intruding the same level of the crust, and that the Lugert post-dates the intrusion of the Reformatory. Numerous miarolitic cavities and hydrothermal veins pervade this zone and its surroundings. Both contain appreciable amounts of quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...
.