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Greenbrier Group
The Greenbrier Limestone, also known locally as the "Big Lime", is an extensive limestone unit deposited during the Middle Mississippian Epoch (345.3 ± 2.1 – 326.4 ± 1.6 Ma), part of the Carboniferous Period. This rock stratum is present below ground in much of West Virginia and neighboring Kentucky, and extends somewhat into adjacent western Maryland and southwestern Virginia. The name derives from the Greenbrier River in West Virginia. Greenbrier Limestone is in some places more than 400 feet (120 metres) thick, allowing it to trap large quantities of oil and gas. Since this carbonate rock erodes quickly in the region's wet climate, outcrops are not prominent and are often quarried. The Greenbrier Limestone is subdivided into six stratigraphic Stratigraphy is a branch of geology concerned with the study of rock layers (strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinks Of Gandy
The Sinks of Gandy — also called the Sinks of Gandy Creek, or simply "The Sinks" — are a modestly celebrated cave and underground stream at Osceola in eastern Randolph County, West Virginia, United States. The Sinks are on private property within the Monongahela National Forest. Description The Sinks are a natural tunnel accommodating Gandy Creek, a tributary of Dry Fork, for about 3,000 feet (915 meters) as it passes under a spur of Yokum Knob to reemerge on the opposite side of Randolph County Route 40 (Dry Fork Road). The southern (upstream) entrance to the Sinks, about wide and high, is in a low ledge of limestone in a large depressed meadow. It consists of a simple longitudinal passage, from 4 to high, with a few minor side passages, not much apparent from the main passage. The main cave passage averages 40 to wide, but in some places up to wide. In some sections the stream occupies the entire floor of the passage, but in other sections it is confined to a na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Virginia
Virginia, officially the Commonwealth of Virginia, is a state in the Mid-Atlantic and Southeastern regions of the United States, between the Atlantic Coast and the Appalachian Mountains. The geography and climate of the Commonwealth are shaped by the Blue Ridge Mountains and the Chesapeake Bay, which provide habitat for much of its flora and fauna. The capital of the Commonwealth is Richmond; Virginia Beach is the most-populous city, and Fairfax County is the most-populous political subdivision. The Commonwealth's population was over 8.65million, with 36% of them living in the Baltimore–Washington metropolitan area. The area's history begins with several indigenous groups, including the Powhatan. In 1607, the London Company established the Colony of Virginia as the first permanent English colony in the New World. Virginia's state nickname, the Old Dominion, is a reference to this status. Slave labor and land acquired from displaced native tribes fueled the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Types Of Limestone
This is a list of types of limestone arranged according to location. It includes both formal stratigraphic unit names and less formal designations. Africa Egypt *Tura limestone, used for the Great Pyramid casing stones *Mokattam limestone; Great Pyramid core stones and head of the Great Sphinx are of the "Member III" stratum * Galala marble (a type of limestone, not a true marble) Asia India * * Israel (West Bank) * * Europe Austria * Belgium *, (not a "true marble"; Devonian limestone) * * Croatia * France * *, or "Paris stone" (city buildings are widely faced with it) **, or Oise, limestone (variety of Lutetian) * *, in the Loire Valley Germany * * Gibraltar * Ireland * , not a "true marble"; fossiliferous Carboniferous limestone. Italy * , not a "true marble"; fossiliferous limestone United Kingdom England: * (not a "true marble"; Carboniferous limestone) * * * , the famous London Stone is made of this. * (not a "true slate"; thin-bedded limestone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solutional Cave
A solutional cave, solution cave, or karst cave is a cave usually formed in the soluble rock limestone. It is the most frequently occurring type of cave. It can also form in other rocks, including chalk, dolomite, marble, salt beds, and gypsum. Process Bedrock is dissolved by natural acid in groundwater that seeps through bedding-planes, faults, joints and so on. Over geological epochs these openings expand as the walls are dissolved to become caves or cave systems. The portions of a solutional cave that are below the water table or the local level of the groundwater will be flooded. Limestone caves The largest and most abundant solutional caves are located in limestone. Limestone caves are often adorned with calcium carbonate formations produced through slow precipitation. These include flowstones, stalactites, stalagmites, helictites, soda straws, calcite rafts and columns. These secondary mineral deposits in caves are called ''speleothems''. Carbonic acid dissoluti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oolite
Oolite or oölite (''egg stone'') is a sedimentary rock formed from ooids, spherical grains composed of concentric layers. The name derives from the Ancient Greek word for egg (ᾠόν). Strictly, oolites consist of ooids of diameter 0.25–2 millimetres; rocks composed of ooids larger than 2 mm are called pisolites. The term ''oolith'' can refer to oolite or individual ooids. Composition Ooids are most commonly composed of calcium carbonate ( calcite or aragonite), but can be composed of phosphate, clays, chert, dolomite or iron minerals, including hematite. Dolomitic and chert ooids are most likely the result of the replacement of the original texture in limestone. Oolitic hematite occurs at Red Mountain near Birmingham, Alabama, along with oolitic limestone. They are usually formed in warm, supersaturated, shallow, highly agitated marine water intertidal environments, though some are formed in inland lakes. The mechanism of formation starts with a small fragment of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Packstone
Under the Dunham classification (Dunham, 1962Dunham, R.J. (1962) Classification of carbonate rocks according to depositional texture. In: Classification of Carbonate Rocks (Ed. W.E. Ham), Am. Assoc. Pet. Geol. Mem., 1, 108–121.) system of limestones, a packstone is defined as a grain-supported carbonate rock that contains 1% or more mud-grade fraction. This definition has been clarified by Lokier and Al Junaibi (2016){{Cite journal, last=Lokier, first=Stephen W., last2=Al Junaibi, first2=Mariam, date=2016-12-01, title=The petrographic description of carbonate facies: are we all speaking the same language?, journal=Sedimentology, language=en, volume=63, issue=7, pages=1843–1885, doi=10.1111/sed.12293, issn=1365-3091, doi-access=free as ''a carbonate-dominated lithology containing carbonate mud (2 mm''. The identification of packstone A study of the adoption and use of carbonate classification systems by Lokier and Al Junaibi (2016) identified three common problems encountered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grainstone
Under the Dunham classification (Dunham, 1962) system of limestones, a grainstone is defined as a grain-supported carbonate rock that contains less than 1% mud-grade material. This definition has recently been clarified as ''a carbonate-dominated rock that does not contain any carbonate mud and where less than 10% of the components are larger than 2 mm.'' The spaces between grains may be empty (pores) or filled by cement. The identification of grainstone The presence of any primary carbonate mud precludes a classification of grainstone. A study of the use of carbonate classification systems by Lokier and Al Junaibi (2016) highlighted that the most common source of confusion in the classification of grainstone was to misidentify fine-grained internal micrite, generated by in-situ processes, as clay–silt grade sediment - thus resulting in the misidentification of grainstone as packstone Under the Dunham classification (Dunham, 1962Dunham, R.J. (1962) Classification of carbonate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratigraphic
Stratigraphy is a branch of geology concerned with the study of rock layers (strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subfields: lithostratigraphy (lithologic stratigraphy), biostratigraphy (biologic stratigraphy), and chronostratigraphy (stratigraphy by age). Historical development Catholic priest Nicholas Steno established the theoretical basis for stratigraphy when he introduced the law of superposition, the principle of original horizontality and the principle of lateral continuity in a 1669 work on the fossilization of organic remains in layers of sediment. The first practical large-scale application of stratigraphy was by William Smith in the 1790s and early 19th century. Known as the "Father of English geology", Smith recognized the significance of strata or rock layering and the importance of fossil markers for correlating strata; he created the first geologic map o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonate Rock
Carbonate rocks are a class of sedimentary rocks composed primarily of carbonate minerals. The two major types are limestone, which is composed of calcite or aragonite (different crystal forms of CaCO3), and dolomite rock (also known as dolostone), which is composed of mineral dolomite (CaMg(CO3)2). Calcite can be either dissolved by groundwater or precipitated by groundwater, depending on several factors including the water temperature, pH, and dissolved ion concentrations. Calcite exhibits an unusual characteristic called retrograde solubility in which it becomes less soluble in water as the temperature increases. When conditions are right for precipitation, calcite forms mineral coatings that cement the existing rock grains together or it can fill fractures. Karst topography and caves develop in carbonate rocks because of their solubility in dilute acidic groundwater. Cooling groundwater or mixing of different groundwaters will also create conditions suitable for cave ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratum
In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as either '' bedding surfaces'' or ''bedding planes''.Salvador, A. ed., 1994. ''International stratigraphic guide: a guide to stratigraphic classification, terminology, and procedure. 2nd ed.'' Boulder, Colorado, The Geological Society of America, Inc., 215 pp. . Prior to the publication of the International Stratigraphic Guide, older publications have defined a stratum as either being either equivalent to a single bed or composed of a number of beds; as a layer greater than 1 cm in thickness and constituting a part of a bed; or a general term that includes both ''bed'' and ''lamina''.Neuendorf, K.K.E., Mehl, Jr., J.P., and Jackson, J.A. , eds., 2005. ''Glossary of Geology'' 5th ed. Alexandria, Virginia, American Geological Institute. 779 pp. . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ''Carboniferous'' means "coal-bearing", from the Latin '' carbō'' ("coal") and '' ferō'' ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern 'system' names, it was coined by geologists William Conybeare and William Phillips in 1822, based on a study of the British rock succession. The Carboniferous is often treated in North America as two geological periods, the earlier Mississippian and the later Pennsylvanian. Terrestrial animal life was well established by the Carboniferous Period. Tetrapods (four limbed vertebrates), which had originated from lobe-finned fish during the preceding Devonian, became pentadactylous in and diversified during the Carboniferous, including early amphibian line ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mississippian Age
The Mississippian ( , also known as Lower Carboniferous or Early Carboniferous) is a subperiod in the geologic timescale or a subsystem of the geologic record. It is the earlier of two subperiods of the Carboniferous period lasting from roughly 358.9 to 323.2 million years ago. As with most other geochronologic units, the rock beds that define the Mississippian are well identified, but the exact start and end dates are uncertain by a few million years. The Mississippian is so named because rocks with this age are exposed in the Mississippi Valley. The Mississippian was a period of marine transgression in the Northern Hemisphere: the sea level was so high that only the Fennoscandian Shield and the Laurentian Shield were dry land. The cratons were surrounded by extensive delta systems and lagoons, and carbonate sedimentation on the surrounding continental platforms, covered by shallow seas. In North America, where the interval consists primarily of marine limestones, it is treate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
