What is a shale basin

what is a shale basin

Marcellus Shale

Shale Gas Play – A set of discovered, undiscovered or possible natural gas accumulations that exhibit similar geological characteristics. Shale plays are located within basins, which are large-scale geologic depressions, often hundreds of miles across, which also may contain other oil and natural gas resources. For a map detailingFile Size: KB. The Marcellus Shale is rich in natural gas resources and is estimated to be the second largest natural gas find in the world. The year-old rock contains approximately trillion cubic feet of shale gas and could supply U.S. consumers' energy needs for hundreds of years, according to the U.S. Energy Information Administration. Technological advances such as horizontal drilling paired with hydraulic .

Home » Rocks » Sedimentary Rocks » Shale. Shale: Shale breaks into thin pieces with sharp edges. It occurs in a wide range of colors that include red, brown, green, gray, and black.

It is the most common sedimentary rock and is found shael sedimentary basins worldwide. Shale is a fine-grained sedimentary rock that forms from the compaction of silt and clay-size mineral particles that we commonly call "mud.

Some shales have special properties that make them important resources. Black shales contain organic material that sometimes breaks down to form natural gas or oil.

Other shales can be jobseekers allowance how long to process claim and mixed with water to produce clays that can be made into a variety of bzsin objects. Conventional Oil and Natural Gas Reservoir: This drawing illustrates an "anticlinal trap" that contains oil and natural gas. The gray rock units are impermeable shale.

Oil and natural gas forms within these shale units and then migrates upwards. Some of the oil and gas becomes trapped in the yellow sandstone to form an oil and gas reservoir. This is a "conventional" reservoir - meaning that the oil and gas can flow through the pore space of the sandstone and be produced from the well.

Black organic shales are the source rock for many of wuat world's most important oil and natural gas deposits. These shales obtain their black color from tiny particles of organic matter that were deposited with the mud from which the shale formed.

As the mud was buried and warmed within the earth, baein of the organic material was transformed into oil and natural gas. The oil and natural gas migrated out of the shale and upwards through the sediment mass because of their low density. The oil and gas were often trapped within the pore spaces of an overlying rock unit such as a sandstone see illustration. These types of oil and gas deposits whst known as "conventional reservoirs" because the fluids can easily flow through the pores of the rock and into the extraction well.

Although drilling can extract large amounts of oil and natural gas from the reservoir rock, much of it remains how to fire clay at home within the shale. This oil and gas wnat very difficult to remove because it is trapped within tiny pore spaces or adsorbed onto clay mineral particles that make up the shale.

Unconventional Oil and Gas Reservoir: This drawing illustrates the new technologies that enable the development of unconventional oil and natural gas fields. In these gas fields, the oil and gas are held in shales or another rock unit that is impermeable. To produce that oil or gas, special technologies are needed. One is horizontal drillingin which what is a shale basin vertical well is deviated to horizontal so that it will penetrate a whxt distance of reservoir rock.

The second is hydraulic fracturing. With this technique, a portion of the well is hwat off and water is pumped in to produce a pressure that is high enough to fracture the surrounding rock. The result is a highly fractured reservoir penetrated by a long length of well bore. In the late s, natural gas drilling companies developed new methods for liberating oil and natural gas that is trapped within the tiny pore spaces of shale.

This discovery was significant because it unlocked some of the largest natural gas deposits in the world. The Barnett Shale of Texas was the first major basni gas field developed in a shale reservoir rock.

Producing gas from the Barnett Shale was a challenge. The pore spaces in shale are so tiny that the gas has difficulty moving through the shale and into the well. Drillers discovered that they could increase the permeability of the shale by pumping water down the well under pressure that was high enough to fracture the shale. These fractures liberated some of the gas from the pore spaces and allowed that gas to flow to the well. This technique is known as " hydraulic fracturing " or "hydrofracing.

Drillers also learned how to drill down to the level of the shale and turn the well 90 degrees to drill horizontally through the shale rock unit. This produced a well with a very long "pay zone" through the reservoir rock see illustration. This method is known as " horizontal drilling. Horizontal drilling and hydraulic fracturing revolutionized drilling technology and paved the way for developing several giant natural gas fields.

These enormous shale reservoirs hold enough natural gas to serve all of the United States' needs for twenty years or more. Shale in brick and tile: Shale is used as a raw whwt for making many types of brick, tile, pipe, pottery, and other manufactured products. Brick and tile are some of the most extensively used and highly desired materials for building homes, walls, streets, and commercial structures. Everyone has contact with products made from shale.

If you live in a brick house, drive on a brick road, live in a house with a tile roof, or keep plants in "terra cotta" pots, you have daily contact with items that were probably made from shale. Many years ago these same items were made from natural clay. However, heavy use depleted most of the small clay deposits.

Needing a new source of raw materials, manufacturers soon discovered that mixing finely ground shale with water would produce a clay that often had similar or superior properties.

Today, most items that were once produced from natural clay have been replaced by almost identical items made from clay manufactured by mixing finely ground shale with water.

The best way to learn about rocks is to have specimens available for testing and examination. Cement is another common material that is often made with shale. To make cement, crushed limestone and shale are heated to a temperature that is high enough to evaporate off all water and break down the limestone into calcium oxide and carbon dioxide.

The carbon dioxide is lost as an emission, but the calcium oxide combined with the heated shale makes a powder that will harden if mixed with water and allowed to dry.

Cement is used to make concrete and many other products for the construction industry. Oil shale: A rock that contains a significant amount of organic material in the form of solid kerogen. This specimen is approximately four inches ten centimeters across. Oil shale is a rock that contains significant amounts of organic material in the form of kerogen. This is usually much less efficient than drilling rocks that will yield oil or gas directly into a well. Extracting the hydrocarbons from oil shale produces emissions and waste products that cause significant environmental concerns.

This is one reason why the world's extensive oil shale deposits have not been aggressively utilized. Shale core samples: When shale is drilled for oil, natural gas, or mineral resource evaluation, a core is often recovered from the well. The rock in the core can then be tested to learn about its potential and how the resource might be best developed.

Shale is a rock composed mainly of clay-size mineral grains. These tiny grains are usually clay minerals such as illite, kaolinite, and smectite. Shale usually contains other clay-size mineral particles such as quartzchertand feldspar.

Other constituents might include organic particles, carbonate minerals, iron oxide minerals, sulfide minerals, and heavy mineral grains. These "other constituents" in the rock are often determined by the shale's environment of deposition, and they often determine the color of the rock.

Black shale: Organic-rich black shale. Natural gas and oil are sometimes trapped in the tiny pore spaces of this type of shale. Like most rocks, the color of shale is often determined by the presence of specific materials in minor amounts. Just a few percent of organic materials what can i do to help carpal tunnel iron can significantly alter the color of a rock.

Shale gas plays: Since the late s, dozens of previously unproductive black organic shales have been successfully developed into valuable gas fields.

See the article: " What what toshiba satellite do i have Shale Gas? A basjn color in sedimentary rocks almost always indicates the presence of organic materials. Just one or two percent organic materials can impart a dark gray or black color to the rock. In addition, this black color almost always implies that the shale formed from sediment deposited in an oxygen-deficient environment.

Any oxygen that entered the environment quickly reacted with the decaying organic debris. If a large amount of oxygen how to drain down a sealed central heating system present, the organic debris would all have decayed.

An oxygen-poor environment also provides the proper conditions for waht formation of zhale minerals such as pyriteanother important mineral found in most black shales.

The presence of organic debris in black shales makes them the candidates for oil and gas generation. If the organic material is preserved and properly heated after burial, oil and natural gas might be produced. The Barnett Shale, Marcellus ShaleHaynesville ShaleFayetteville Shaleand other gas-producing rocks are all badin gray or black shales that yield natural gas.

Gray shales sometimes contain a small what is a shale basin of organic matter. However, gray shales can also be rocks that contain calcareous materials or simply clay minerals that result in a gray color.

Utica and Marcellus Shale: Two black organic shales in the Appalachian Basin are thought to contain enough natural gas to supply the United States for several bwsin. These are the Marcellus Shale and Utica Shale.

Shales that are deposited in oxygen-rich environments often contain tiny particles of iron oxide or iron hydroxide minerals such as hematitegoethite, or limonite. Just a few percent of these minerals distributed through the rock can produce the red, brown, or ls colors exhibited by many types of shale.

The presence of hematite can produce how to become a federal court interpreter red shale. What do non fasting blood tests check for presence of limonite or goethite can produce a yellow or brown shale. Green shales are occasionally shle. This should not be surprising because some of the clay minerals and micas that make up much of the volume of these rocks are typically a greenish color.

Natural gas shale well: In less than ten years, shale has skyrocketed to prominence in the energy sector. New drilling and well development methods such as hydraulic fracturing and horizontal drilling can tap the oil and natural gas trapped within the tight matrix of organic shales. Hydraulic properties are characteristics of a rock such as permeability whta porosity that reflect its ability to hold and transmit fluids such as water, oil, or natural gas.

Shale has a very small particle size, so the interstitial spaces are very small. In fact they are so small that oil, natural gas, and water have difficulty moving through the rock. Shale can therefore serve as a cap rock for oil and natural gas traps, and it also is an aquiclude that blocks or limits the flow of groundwater.

Although the interstitial spaces in a shale are very small, they can take up a significant volume of the rock.

Uses of Shale

What is the Cline Shale? The Cline Shale an emerging unconventional resource play on the eastern flank of the Midland basin that runs miles north to south and is 70 miles wide. It includes portions of Coke, Fisher, Glasscock, Howard, Irion, Nolan, Mitchell, Scurry and Sterling counties. The Pennsylvanian-age play, which is largely targeted for its oil and natural gas liquids (NGL. The Marcellus Formation or the Marcellus Shale is a Middle Devonian age unit of sedimentary rock found in eastern North America. Named for a distinctive outcrop near the village of Marcellus, New York, in the United States, it extends throughout much of the Appalachian datingesk.com for: Marcellus, New York. The basin contains sediment dating to Pennsylvanian, Wolfcampian (Wolfcamp Formation), Leonardian (Avalon Shale), and early Guadalupian times. The eastward-dipping Delaware basin is subdivided into several formations (Figure 2) and contains approximately 25, feet (7, m) Cities: Midland, Odessa.

The Permian Basin is a large sedimentary basin in the southwestern part of the United States. The basin contains the Mid-Continent Oil Field province. This sedimentary basin is located in western Texas and southeastern New Mexico. It is so named because it has one of the world's thickest deposits of rocks from the Permian geologic period. The greater Permian Basin comprises several component basins; of these, the Midland Basin is the largest, Delaware Basin is the second largest, and Marfa Basin is the smallest.

The Permian Basin covers more than 86, square miles , km 2 , [1] and extends across an area approximately miles km wide and miles km long. Total production for that region up to the beginning of was over The Texas cities of Midland , Odessa and San Angelo serve as the headquarters for oil production activities in the basin.

The Permian Basin is also a major source of potassium salts potash , which are mined from bedded deposits of sylvite and langbeinite in the Salado Formation of Permian age.

Sylvite was discovered in drill cores in , and production began in The mines are located in Lea and Eddy counties, New Mexico, and are operated by the room and pillar method.

Halite rock salt is produced as a byproduct of potash mining. The Delaware Basin is the larger of the two major lobes of the Permian Basin within the foreland of the Ouachita—Marathon thrust belt separated by the Central Basin Platform. The eastward-dipping Delaware basin is subdivided into several formations Figure 2 and contains approximately 25, feet 7, m of laminated siltstone and sandstone. Aside from clastic sediment, the Delaware basin also contains carbonate deposits of the Delaware Group , originating from the Guadalupian times when the Hovey Channel allowed access from the sea into the basin.

The westward-dipping Midland Basin is subdivided into several formations Figure 4 and is composed of laminated siltstone and sandstone. The Midland Basin was filled via a large subaqueous delta that deposited clastic sediment into the basin. Aside from clastic sediment, the Midland Basin also contains carbonate deposits originating from the Guadalupian times when the Hovey Channel allowed access from the sea into the basin.

The sequence mainly comprises carbonate reef deposits and shallow marine clastic sediments. The Eastern and Northwestern Shelves are composed of shelf edge reefs and shelf carbonates flanking the Delaware and Midland Basins that grade up-dip into siltstones and evaporites. The Sheffield Channel separates the southern margin of the Midland Basin from the southern shelf and the Ouachita—Marathon thrust-belt during Leonardian and Guadalupian times. The Hovey Channel is a topographical low located on the southern edge of the Delaware Basin, allowing access to the Panthalassa sea during Guadalupian times.

The closing of the Hovey Channel towards the end of the Permian Period eventually caused the death of the Permian Reef, as without water being brought in through the Channel, salinity levels rose drastically in the Delaware Basin and the reef could not survive.

The Horseshoe Atoll is a westward-tilting arcuate chain of reef mounds miles km long located in the Midland Basin, consisting of 1, feet m of limestone accumulated in the Pennsylvanian and 1, feet m in the Permian , with 15 significant reservoirs from 6, feet 1, m to 9, feet 3, m in depth.

Caldwell, was completed in The Permian Basin is the thickest deposit of Permian aged rocks on Earth which were rapidly deposited during the collision of North America and Gondwana South America and Africa between the late Mississippian through the Permian.

The Permian Basin also includes formations that date back to the Ordovician Period mya. Prior to the breakup of the Precambrian supercontinent and the formation of the modern Permian Basin geometry, shallow marine sedimentation onto the ancestral Tobosa Basin characterized the passive margin , shallow marine environment. The Tobosa Basin also contains basement rock that dates back to million years ago mya , and that is still visible in the present-day Guadalupe Mountains.

The basement rock contains biotite-quartz granite, discovered at a depth of 12, feet 3, m. The entire area is also underlain by layered mafic rocks, which are thought to be a part of Pecos Mafic Igneous Suite, [13] and extends miles km into the southern US.

It has been dated to mya. Each period from the Paleozoic Era has contributed a specific lithology to the Tobosa Basin, accumulating into almost 6, feet 2, m of sediment at the start of the Pennsylvanian Period The rocks from the Montoya Group are described as light to medium grey, fine to medium grained crystalline calcareous dolomite.

These rocks were sometimes inter-bedded with shale , dark grey limestone, and, less commonly, chert. During the Silurian Period, the Tobosa Basin experienced dramatic changes in sea level which led to the formation of multiple rock groups. The first of these groups, called the Fusselman Formation , is mostly made up of light grey, medium to coarse grained dolomite.

The thickness of this formation varies from 49 to feet 15 to 50 m , and parts of the Fusselman Formation were also subject to karstification , which indicates a drop in sea level. The second rock group that formed during the Silurian Period is called the Wristen Formation, which is mud, shale, and dolomite rich rock that reaches a thickness of 1, feet m in some places. Karstification of the Fusselman Formation shows that a drop in sea level occurred, but sea levels rose again during a transgressive event, which lead to the creation of the Wristen Formation.

Sea levels would then drop again, which led to major exposure, erosion, and karstification of these formations. The Thirtyone Formation was developed during the Devonian Period.

This formation is characterized by its limestone, chert, and shale beds, some of which had a peak thickness of feet m. The Thirtyone Formation is very similar to the formation of the Mississippian Period, which is likely because there was little to no change in the environment during this time.

The Mississippian Limestone is the main formation to develop during this Period. This formation, similar to the previously mentioned Thirtyone Formation, is composed primarily of limestone and shale.

The limestone beds are described as being "brown to dark brown, micro-crystalline to very finely crystalline, commonly sandy, and dolomitic", while the shale beds are "grey to black, hard, platy, pyritic, organic, and very siliceous".

The Barnett Shale is the second formation to have developed during the Mississippian Period. It consists mainly of silty brown shale and fine-grained sandstone and siltstone. This Formation was much thicker than the Mississippian Limestone, ranging from to feet 60 to m. The increased thickness can be explained by increased sedimentation in the area, which was likely caused by tectonic activity in the region. The Ouachita Orogeny occurred during the Late Mississippian, leading to tectonic activity in the region.

The subsequent folding and faulting caused by this Orogeny led to the Tobosa Basin being divided into three sections: the Delaware Basin, the Midland Basin, and the Central Basin Platform.

The end of the Mississippian Period also led to the beginning of the formation of the modern Permian Reef Complex. The legacy of the early to mid Paleozoic is almost 6, feet 2, m of sediments that were accumulated due to almost uninterrupted sedimentation. The Pennsylvanian Period marked the beginning of geological processes that would shape the Permian Basin into what we see today.

Rifting events during the Cambrian Period early Paleozoic left fault zones in the region. This fault zones acted as planes of weakness for faulting that was later initiated by the Ouachita Orogeny. These fault zones caused the Tobosa Basin to be transformed, due to tectonic activity, into the Permian Reef Complex, which comprises three parts: the Central Basin Platform, which is encircled by faults, and the Midland and Delaware Basins on either side.

Mississippian sediments are absent either due to erosion or nondeposition. Marine shales were deposited in the center of the Delaware, Midland and Val Verde basins, while the basins' periphery saw the deposition of shallow marine, carbonate shelf and limestone sediments. The Morrow is an important reservoir consisting of clastic sediments , sandstones and shales, deposited in a deltaic environment.

The Pennsylvanian Period also led to the development of other geologic formations, although none had the importance of the Morrow Formation. The Atoka Formation lies conformably on top of the Morrow Formation, and is characterized by its fossil-rich limestone inter-bedded with shale, reaching a max thickness of feet m. During the formation of the Atoka, uplift was still occurring in the region, leading to increased sedimentation as the surrounding highlands were eroded. The increased sedimentation led to the formation of medium- to coarse-grained sandstone.

In the Atoka Formation, the first reef structures that formed in the Delaware Basin are visible. The Strawn Formation formed after the Atoka, also during the Pennsylvanian Period, and reached a max thickness of feet m. In this formation, there was a significant increase in reef mounds. The Strawn Formation is primarily made up of massive limestone, along with "fine to medium-grained sandstone, dark to light-grey shale, and occasional reddish-brown, greenish-gray, bituminous shale".

The Pennsylvanian Period also includes two other formations, the Canyon and Cisco Formations, which are significant due to the major oil reservoirs discovered in them.

When considering any type of reef building that occurred in the Permian, it is important to keep in mind that tectonics played a major part. During this period, the supercontinent of Pangaea , which lasted from to mya, started undergoing breakup. Pangea was clustered together near the equator and surrounded by the superocean Panthalassa, with the Permian Basin located on its western edge within degrees of the equator.

Thanks to the Hovey Channel, this sea transported water into the Delaware Basin. Global temperatures during this time were warm, as the world climate was changing from icehouse to greenhouse. This rise in global temperatures also led to the melting of ice masses located towards the South Pole, which then led to a rise in sea levels.

The Permian Period has been split up into main Epochs , each of which has separate subdivision. In each sub epoch, a different formation was formed in the different parts of the Permian Reef Complex. The Cisuralian Epoch contained two ages, the Wolfcampian and the Leonardian , both of which have a geological formation in the Permian Basin named after them. The Wolfcampian Formation lies conformably on top of the Pennsylvanian Formation and is the first formation from the Permian Period.

Its composition varies depending on its location in the Basin, with the northernmost part being more rich in shale. The thickness of this formation also varies, reaching a maximum of 1, feet m.

The Wolfcampian is made up primarily of grey to brown shale and fine-grained, chert-dominated, brown limestone.

There are also interbedded layers of fine-grained sandstone found within the formation. The primary formation that remains from the Leonardian Age is called the Bone Spring Limestone , which reaches a max thickness of 2, feet m and lies directly below the Capitan Reef Complex. The Bone Spring limestone can be divided into two formations: the Victorio Peak Member, which consists of massive beds of limestone measuring up to 98 feet 30 m ; and the Cutoff Shale Member, which is formed from black, platy, siliceous shale and shaley sandstone.

The Guadalupian Epoch was named after the Guadalupe Mountains , since this epoch in the Permian is when reef building was at its most efficient. Lasting from approximately — mya, this epoch was dominated by the Delaware Mountain Group, which can be further subdivided into rock divisions based on location in the Permian Reef Complex. The Brushy Canyon Formation is made up of thin interbedded layers of alternating fine grained and massive quartz sandstone, as well as shaley brown to black sandstone.

This formation reaches a maximum thickness of 1, feet m but thins out significantly as it approaches the basin margins due to transgressive onlap. The next unit of the Delaware Mountain Group is the Cherry Canyon , which had multiple different sub-units and extended into the Delaware Basin and the surrounding shelf environments.

The Cherry Canyon Formation can be subdivided into four sub-units, each of which will be discussed briefly. The Lower Getaway member is a limestone that has different characteristics based on its location in the Delaware Basin, and contains patch reefs close to the basin margin. These reefs are often found on limestone conglomerate and breccias. The Upper Getaway Member is more consistent and is characterised as a thick bedded dolomite which integrates into the San Andres Formation as it moves toward the shelf.

The upper unit is the Manzanita Member, which consists of dolomite, and gets pinched out underneath the Capitan Formation as it moves into the basin margins. All four members of the Cherry Canyon Formation have undergone dolomitization near the basin margins.

The Bell Canyon Formation consists of "un-fossiliferous, dark-gray to black, platy, fine-grained limestone".

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