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51-534: The Craven Basin is a sedimentary basin in northern England , having the shape of a southerly-tilted graben which was active during the Carboniferous period. It is one of a series of such basins which developed across northern England in this period separating upstanding blocks which were typically underlain by buoyant granites . The basin trends roughly east–west and is bounded by the Lake District block to

102-422: A convergent plate tectonic boundary in the gap between an active volcanic arc and the associated trench , thus above the subducting oceanic plate. The formation of a forearc basin is often created by the vertical growth of an accretionary wedge that acts as a linear dam, parallel to the volcanic arc, creating a depression in which sediments can accumulate. Trench basins are deep linear depressions formed where

153-445: A load is placed on the lithosphere, it will tend to flex in the manner of an elastic plate. The magnitude of the lithospheric flexure is a function of the imposed load and the flexural rigidity of the lithosphere, and the wavelength of flexure is a function of flexural rigidity of the lithospheric plate. Flexural rigidity is in itself, a function of the lithospheric mineral composition, thermal regime, and effective elastic thickness of

204-478: A much higher cost per acre. Production peaked in 1986, but in the early 2000s significant increases in production began because of application of horizontal drilling techniques, especially in the Bakken Formation . Cumulative basin production totals about 3.8 billion barrels (600,000,000 m ) of oil and 470 billion cubic feet (1.3 × 10  m ) of natural gas. The largest oil fields are listed in

255-698: A promising lease 30 miles north-east of Williston, North Dakota , and on April 4, 1951, discovered oil on the Nesson Anticline, with the Amerada Hess Corporation Clarence Iverson #1 well. Other oil firms rushed in to buy up leases on farm land to explore for oil and by 1954 80% of the possible oil producing areas were under lease. Royal Dutch Shell at that time had leases on over 8 million acres. Many local farmers and area speculators became instant millionaires, leasing land at an average of $ 25 an acre and then selling those leases back at

306-573: A purely scientific perspective because their sedimentary fill provides a record of Earth's history during the time in which the basin was actively receiving sediment. More than six hundred sedimentary basins have been identified worldwide. They range in areal size from tens of square kilometers to well over a million, and their sedimentary fills range from one to almost twenty kilometers in thickness. A dozen or so common types of sedimentary basins are widely recognized and several classification schemes are proposed, however no single classification scheme

357-566: A regional depression that provides accommodation space for accumulation of sediments. Over millions or tens or hundreds of millions of years the deposition of sediment , primarily gravity-driven transportation of water-borne eroded material, acts to fill the depression. As the sediments are buried, they are subject to increasing pressure and begin the processes of compaction and lithification that transform them into sedimentary rock . Sedimentary basins are created by deformation of Earth's lithosphere in diverse geological settings, usually as

408-417: A result of plate tectonic activity. Mechanisms of crustal deformation that lead to subsidence and sedimentary basin formation include the thinning of underlying crust; depression of the crust by sedimentary, tectonic or volcanic loading; or changes in the thickness or density of underlying or adjacent lithosphere . Once the process of basin formation has begun, the weight of the sediments being deposited in

459-650: A result of the closing of a major ocean through continental collision resulting from plate tectonics. As a result the sedimentary record of inactive passive margins often are found as thick sedimentary sequences in mountain belts. For example the passive margins of the ancient Tethys Ocean are found in the mountain belts of the Alps and Himalayas that formed when the Tethys closed. Many authors recognize two subtypes of foreland basins: Peripheral foreland basins Retroarc foreland basins A sedimentary basin formed in association with

510-462: A rift process going to completion to form a passive margin. In this case the sedimentary rocks of the rift basin phase are overlain by those rocks deposited during the passive margin phase. Hybrid basins where a single regional basin results from the processes that are characteristic of multiple of these types are also possible. Terrestrial rift valleys Proto-oceanic rift troughs Passive margins are long-lived and generally become inactive only as

561-567: A sedimentary basin even if it is no longer a bathymetric or topographic depression. The Williston Basin , Molasse basin and Magallanes Basin are examples of sedimentary basins that are no longer depressions. Basins formed in different tectonic regimes vary in their preservation potential . Intracratonic basins, which form on highly-stable continental interiors, have a high probability of preservation. In contrast, sedimentary basins formed on oceanic crust are likely to be destroyed by subduction . Continental margins formed when new ocean basins like

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612-404: A subducting oceanic plate descends into the mantle, beneath the overriding continental (Andean type) or oceanic plate (Mariana type). Trenches form in the deep ocean but, particularly where the overriding plate is continental crust they can accumulate thick sequences of sediments from eroding coastal mountains. Smaller 'trench slope basins' can form in association with a trench can form directly atop

663-592: A wide range of geologic ages, as indicated by the generalized stratigraphic column. In 1913, shallow gas was discovered in an Upper Cretaceous sandstone on the Cedar Creek Anticline , and oil was discovered on the same anticline in 1936. The basin did not become a major oil province until the 1950s when large fields were discovered in North Dakota. Amerada Corporation began the search in 1946. After four years of testing and mapping they started drilling at

714-516: Is a piece of rubber, which thins in the middle when stretched.) An example of a basin caused by lithospheric stretching is the North Sea – also an important location for significant hydrocarbon reserves. Another such feature is the Basin and Range Province which covers most of Nevada, forming a series of horst and graben structures. Tectonic extension at divergent boundaries where continental rifting

765-572: Is large enough and long-lived enough to create a sedimentary basin often called a pull-apart basin or strike-slip basin. These basins are often roughly rhombohedral in shape and may be called a rhombochasm . A classic rhombochasm is illustrated by the Dead Sea rift, where northward movement of the Arabian Plate relative to the Anatolian Plate has created a strike slip basin. The opposite effect

816-540: Is occurring can create a nascent ocean basin leading to either an ocean or the failure of the rift zone . Another expression of lithospheric stretching results in the formation of ocean basins with central ridges. The Red Sea is in fact an incipient ocean, in a plate tectonic context. The mouth of the Red Sea is also a tectonic triple junction where the Indian Ocean Ridge, Red Sea Rift and East African Rift meet. This

867-458: Is particularly measurable and observable with oceanic crust, as there is a well-established correlation between the age of the underlying crust and depth of the ocean . As newly-formed oceanic crust cools over a period of tens of millions of years. This is an important contribution to subsidence in rift basins, backarc basins and passive margins where they are underlain by newly-formed oceanic crust. In strike-slip tectonic settings, deformation of

918-457: Is recognized as the standard. Most sedimentary basin classification schemes are based on one or more of these interrelated criteria: Although no one basin classification scheme has been widely adopted, several common types of sedimentary basins are widely accepted and well understood as distinct types. Over its complete lifespan a single sedimentary basin can go through multiple phases and evolve from one of these types to another, such as

969-535: Is that of transpression , where converging movement of a curved fault plane causes collision of the opposing sides of the fault. An example is the San Bernardino Mountains north of Los Angeles, which result from convergence along a curve in the San Andreas Fault system. The Northridge earthquake was caused by vertical movement along local thrust and reverse faults "bunching up" against the bend in

1020-416: Is the only place on the planet where such a triple junction in oceanic crust is exposed subaerially . This is due to a high thermal buoyancy ( thermal subsidence ) of the junction, and also to a local crumpled zone of seafloor crust acting as a dam against the Red Sea. Lithospheric flexure is another geodynamic mechanism that can cause regional subsidence resulting in the creation of a sedimentary basin. If

1071-466: Is thus an important area of study for purely scientific and academic reasons. There are however important economic incentives as well for understanding the processes of sedimentary basin formation and evolution because almost all of the world's fossil fuel reserves were formed in sedimentary basins. All of these perspectives on the history of a particular region are based on the study of a large three-dimensional body of sedimentary rocks that resulted from

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1122-539: The Lewis and Clark Expedition . Mining of the coal began in 1873 near Sims, North Dakota , but was soon abandoned. The Northern Pacific Railway took over the mine and developed the lignite beds as the Northern Pacific Coal Company. Other mines followed near Minot, North Dakota and Dickinson, North Dakota , and the period from 1900 to 1920 saw a large-scale increase in the lignite industry. Strip-mining

1173-589: The Ordovician , Silurian , and Devonian Periods, when thick accumulations of limestone and dolomite, with lesser thicknesses of sandstones, siltstones, shales, and evaporites were laid down. Subsidence continued on a reduced scale into the Mississippian and was largely ended by Pennsylvanian time. Regional subsidence returned during the Mesozoic Era, although total sediment thicknesses were much less than during

1224-643: The Paleozoic . Near the end of the Cretaceous , tectonic activity during the Laramide Orogeny rejuvenated several basement structures in the Williston Basin to produce anticlines that serve as oil traps today. The long history of sedimentary deposition in the Williston Basin included deposition of rocks well suited to serve as hydrocarbon source and reservoir rocks . The basin's oil and gas fields are found in

1275-587: The Trans-Hudson Orogenic Belt that developed in this area about 1.8-1.9 billion years ago, and that created a weak zone that later led to sagging to produce the basin. The Precambrian basement rocks in the center of the basin beneath the city of Williston, North Dakota lie about 16,000 feet (4,900 m) below the surface. Deposition of sediments began in the Williston area during Cambrian time, but subsidence and basin filling were most intense during

1326-762: The Visean . The proven sedimentary fill in the Craven Basin starts with Courceyan age mudstones and limestones of the Chatburn Limestone Group , followed by the similar sediments deposited from Chadian to Asbian times and assigned to the Worston Shale Group . The basal part of this group is the Clitheroe Limestone which is unconformably overlain by the Hodder Mudstone. Completing the group are

1377-554: The Atlantic are created as continents rift apart are likely to have lifespans of hundreds of millions of years, but may be only partially preserved when those ocean basins close as continents collide. Sedimentary basins are of great economic importance. Almost all the world's natural gas and petroleum and all of its coal are found in sedimentary rock. Many metal ores are found in sedimentary rocks formed in particular sedimentary environments. Sedimentary basins are also important from

1428-758: The Hodderense Limestone and Pendleside Limestone. The basin fill is completed by the Brigantian age Bowland Shale Group which comprises the Pendleside Sandstones within what is otherwise a mudstone succession. The boundary between the Craven Basin and the Askrigg Block is defined by the Craven Fault System which comprises the North, Middle and South Craven faults. The last-named actually extends into

1479-852: The Red River is the Ordovician Stony Mountain Formation and Stonewall Formation , followed by the Silurian Interlake Group . During the Devonian , the Williston Basin became the southeastern corner of the Elk Point Basin when the Elk Point Group , Manitoba Group , and Saskatchewan Group were deposited. The Bakken Formation , an organic-rich marine shale , was deposited in the Late Devonian. The Lodgepole Limestone

1530-482: The associated accretionary prism as it grows and changes shape creating ponded basins. Pull-apart basins is are created along major strike-slip faults where a bend in the fault geometry or the splitting of the fault into two or more faults creates tensional forces that cause crustal thinning or stretching due to extension, creating a regional depression. Frequently, the basins are rhombic, S-like or Z-like in shape. A broad comparatively shallow basin formed far from

1581-409: The basin adds a further load on the underlying crust that accentuates subsidence and thus amplifies basin development as a result of isostasy . The long-term preserved geologic record of a sedimentary basin is a large scale contiguous three-dimensional package of sedimentary rocks created during a particular period of geologic time, a 'stratigraphic succession', that geologists continue to refer to as

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1632-575: The basin. There is a reef belt which runs along the line of the Middle Craven Fault between Settle and Cracoe . Sedimentary basin Sedimentary basins are region-scale depressions of the Earth's crust where subsidence has occurred and a thick sequence of sediments have accumulated to form a large three-dimensional body of sedimentary rock . They form when long-term subsidence creates

1683-401: The earth's surface over time. Regional study of these rocks can be used as the primary record for different kinds of scientific investigation aimed at understanding and reconstructing the earth's past plate tectonics (paleotectonics), geography ( paleogeography , climate ( paleoclimatology ), oceans ( paleoceanography ), habitats ( paleoecology and paleobiogeography ). Sedimentary basin analysis

1734-425: The edge of a continental craton as a result of prolonged, broadly distributed but slow subsidence of the continental lithosphere relative to the surrounding area. They are sometimes referred to as intracratonic sag basins. They tend to be subcircular in shape and are commonly filled with shallow water marine or terrestrial sedimentary rocks that remain flat-lying and relatively undeformed over long periods of time due to

1785-439: The effect is believed to be twofold. The lower, hotter part of the lithosphere will "flow" slowly away from the main area being stretched, whilst the upper, cooler and more brittle crust will tend to fault (crack) and fracture. The combined effect of these two mechanisms is for Earth's surface in the area of extension to subside, creating a geographical depression which is then often infilled with water and/or sediments. (An analogy

1836-405: The fill of one or more sedimentary basins over time. The scientific studies of stratigraphy and in recent decades sequence stratigraphy are focused on understanding the three-dimensional architecture, packaging and layering of this body of sedimentary rocks as a record resulting from sedimentary processes acting over time, influenced by global sea level change and regional plate tectonics. Where

1887-580: The following table, showing estimated ultimate recoveries. Potash produced from the Williston Basin makes Canada the world's leading producer of that commodity. The deposits occur in the Middle Devonian Prairie Formation . Major potash-producing companies include Nutrien and Mosaic . The Williston Basin holds large coal deposits, primarily in the Fort Union Formation of mostly Paleogene age, and were first noted during

1938-650: The formation a distinctive green color. The basin started subsiding due to strike-slip movement along northeast–southwest trending faults , resulting in the deposition of the Winnipeg Group, which lies unconformably on the Deadwood. The Winnipeg consists of shallow marine sandstone, shale and shaly carbonate . The Red River Formation lies unconformably on the Winnipeg, and consists of shallow marine carbonate, anhydrite , and salt sedimentation . Conformably overlying

1989-475: The highest concentration. The helium originated through natural radioactive decay of uranium and thorium in Precambrian granitic basement rocks, or Lower Paleozoic shales . The Upper Cambrian Deadwood Formation was transgressively deposited on the low-relief Precambrian surface. The Deadwood is characterized by shallow marine and coastal plain sediments, with abundant glauconite giving

2040-425: The lithosphere occurs primarily in the plane of Earth as a result of near horizontal maximum and minimum principal stresses . Faults associated with these plate boundaries are primarily vertical. Wherever these vertical fault planes encounter bends, movement along the fault can create local areas of compression or tension. When the curve in the fault plane moves apart, a region of transtension occurs and sometimes

2091-405: The lithosphere. Plate tectonic processes that can create sufficient loads on the lithosphere to induce basin-forming processes include: After any kind of sedimentary basin has begun to form, the load created by the water and sediments filling the basin creates additional load, thus causing additional lithospheric flexure and amplifying the original subsidence that created the basin, regardless of

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2142-478: The long-lived tectonic stability of the underlying craton. The geodynamic forces that create them remain poorly understood. Sedimentary basins form as a result of regional subsidence of the lithosphere, mostly as a result of a few geodynamic processes. If the lithosphere is caused to stretch horizontally, by mechanisms such as rifting (which is associated with divergent plate boundaries) or ridge-push or trench-pull (associated with convergent boundaries),

2193-618: The northwest, the Askrigg Block to the northeast and the Central Lancashire High to the south. One distinct section of the basin is a half graben which contains over 3km thickness of late Devonian to Courceyan strata and is referred to as the Bowland Sub-basin. These basins resulted from the crust of the region being subjected to a north–south lateral tension regime which began in the late Devonian and lasted through until

2244-471: The original cause of basin inception. Cooling of a lithospheric plate, particularly young oceanic crust or recently stretched continental crust, causes thermal subsidence . As the plate cools it shrinks and becomes denser through thermal contraction . Analogous to a solid floating in a liquid, as the lithospheric plate gets denser it sinks because it displaces more of the underlying mantle through an equilibrium process known as isostasy . Thermal subsidence

2295-413: The otherwise strike-slip fault environment. The study of sedimentary basins as entities unto themselves is often referred to as sedimentary basin analysis . Study involving quantitative modeling of the dynamic geologic processes by which they evolved is called basin modelling . The sedimentary rocks comprising the fill of sedimentary basins hold the most complete historical record of the evolution of

2346-429: The rocks directly and also very importantly allow paleontologists to study the microfossils they contain ( micropaleontology ). At the time they are being drilled, boreholes are also surveyed by pulling electronic instruments along the length of the borehole in a process known as well logging . Well logging, which is sometimes appropriately called borehole geophysics , uses electromagnetic and radioactive properties of

2397-598: The rocks surrounding the borehole, as well as their interaction with the fluids used in the process of drilling the borehole, to create a continuous record of the rocks along the length of the borehole, displayed as of a family of curves. Comparison of well log curves between multiple boreholes can be used to understand the stratigraphy of a sedimentary basin, particularly if used in conjunction with seismic stratigraphy. Williston Basin The Williston Basin lies above an ancient Precambrian geologic basement feature,

2448-486: The sedimentary rocks comprising a sedimentary basin's fill are exposed at the earth's surface, traditional field geology and aerial photography techniques as well as satellite imagery can be used in the study of sedimentary basins. Much of a sedimentary basin's fill often remains buried below the surface, often submerged in the ocean, and thus cannot be studied directly. Acoustic imaging using seismic reflection acquired through seismic data acquisition and studied through

2499-400: The specific sub-discipline of seismic stratigraphy is the primary means of understanding the three-dimensional architecture of the basin's fill through remote sensing . Direct sampling of the rocks themselves is accomplished via the drilling of boreholes and the retrieval of rock samples in the form of both core samples and drill cuttings . These allow geologists to study small samples of

2550-415: Was common from 1920 until 1940, and 320 mines were in operation by 1940. However, production peaked in 1951, and by 1965, only 38 mines were in operation, while by 1999, only 4. In 1952, helium concentrations were discovered in southwestern Saskatchewan. Production from four wells took place from 1963 to 1977, and resumed again in 2014. The Deadwood Formation, and other Lower Paleozoic formations, had

2601-584: Was deposited during the Mississippian , followed by the Madison Group and the Big Snowy Group . The Tyler Formation was deposited in the Pennsylvanian , and consists of interbedded sandstone, siltstone , shale, and limestone . The overlying Minnelusa Formation is characterized by deposition in alluvial plains , prograding river delta , and barrier island environments. The Minnekahta Formation

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