Misplaced Pages

#877122

48-681: The Appalachian Plateau is a series of rugged dissected plateaus located on the western side of the Appalachian Mountains . The Appalachian Mountains are a range that run from Nova Scotia in Canada to Alabama in the United States. The Appalachian Plateau is the northwestern part of the Appalachian Highlands physiographic division of the United States, stretching from New York state to Alabama . The plateau

96-708: A supereon , but this is also an informal term, not defined by the ICS in its chronostratigraphic guide. Eozoic (from eo- "earliest") was a synonym for pre-Cambrian , or more specifically Archean . A specific date for the origin of life has not been determined. Carbon found in 3.8 billion-year-old rocks (Archean Eon) from islands off western Greenland may be of organic origin. Well-preserved microscopic fossils of bacteria older than 3.46 billion years have been found in Western Australia . Probable fossils 100 million years older have been found in

144-493: A tundra , with lower temperatures, numerous conifer trees, and large mammals, such as mammoths and saber-toothed tigers. Eventually, the climate began to warm up again, the large mammals started to disappear, and the vegetation seen more often today began to flourish. These climatic changes made life more sustainable for the Native Americans. They continued to invent new weapons and made advancements in agriculture until

192-735: A possible 2450 Ma red alga from the Kola Peninsula , 1650 Ma carbonaceous biosignatures in north China, the 1600 Ma Rafatazmia , and a possible 1047 Ma Bangiomorpha red alga from the Canadian Arctic. The earliest fossils widely accepted as complex multicellular organisms date from the Ediacaran Period. A very diverse collection of soft-bodied forms is found in a variety of locations worldwide and date to between 635 and 542 Ma. These are referred to as Ediacaran or Vendian biota . Hard-shelled creatures appeared toward

240-473: Is a second level United States physiographic region , covering parts of the states of New York, Pennsylvania , Ohio , Maryland , West Virginia , Virginia , Kentucky , Tennessee , Alabama , and Georgia . The formation of the plateau began during the Paleozoic Era. Regional uplift during this time caused the area to rise altogether without changing the topography of the land. The eastern side of

288-545: Is estimated that there is around 2,000 species of flora within the Appalachia region. Flowers vary due to elevation and climate of the area of Appalachia region. Different types of flowers in the northern and southern sections of the Appalachia. Flowers such as rhododendron , azalea and mountain laurel can be found in southern regions while up north trees will bear serviceberry , redbud , sourwood , and many others. Fauna such as bison and wolves used to be native to

336-664: Is known to occur during the RNA replication of extant coronaviruses . Evidence of the details of plate motions and other tectonic activity in the Precambrian is difficult to interpret. It is generally believed that small proto-continents existed before 4280 Ma, and that most of the Earth's landmasses collected into a single supercontinent around 1130 Ma. The supercontinent, known as Rodinia , broke up around 750 Ma. A number of glacial periods have been identified going as far back as

384-795: Is still widely known in Britain by the older name of boulder clay. Dissected volcanic plateaus include the Pajarito Plateau in New Mexico , on the skirt of the enormous Valles Caldera . Isolated portions of this plateau are known as mesas , and long, connected portions are known as potreros . The Allegheny Plateau , the Cumberland Plateau , the Ozark Plateau , and the Catskill Mountains in

432-632: Is the Upper Silurian evaporate basin , or basin of chemically formed sedimentary rocks. The Plateau fold belt consists of structurally complex Paleozoic strata which were thrust faulted over the younger evaporates. When the Appalachian mountains were formed, the plateau was lifted. Ridges and valleys all die down underneath the plateau. There are multiple valleys throughout the region which consist of exposed areas of limestone and shale. Archaeologists have evidence that Native Americans in

480-668: Is the earliest part of Earth's history , set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian , the first period of the Phanerozoic Eon , which is named after Cambria , the Latinized name for Wales , where rocks from this age were first studied. The Precambrian accounts for 88% of the Earth's geologic time. The Precambrian is an informal unit of geologic time, subdivided into three eons ( Hadean , Archean , Proterozoic ) of

528-521: Is thought that the Earth coalesced from material in orbit around the Sun at roughly 4,543 Ma, and may have been struck by another planet called Theia shortly after it formed, splitting off material that formed the Moon (see Giant-impact hypothesis ). A stable crust was apparently in place by 4,433 Ma, since zircon crystals from Western Australia have been dated at 4,404 ± 8 Ma. The term "Precambrian"

SECTION 10

#1732773105878

576-731: Is used by geologists and paleontologists for general discussions not requiring a more specific eon name. However, both the United States Geological Survey and the International Commission on Stratigraphy regard the term as informal. Because the span of time falling under the Precambrian consists of three eons (the Hadean , the Archean , and the Proterozoic ), it is sometimes described as

624-416: Is why it is so hard for researchers to determine when they settled in this area. Much like many historic Native American tribes, the early Appalachian inhabitants survived as nomads, following their food on a seasonal basis. Around this period, North America was still recuperating from its last glacial period , and the climate was very different from the present. The climate and habitat more closely resembled

672-534: The Huronian epoch, roughly 2400–2100 Ma. One of the best studied is the Sturtian-Varangian glaciation, around 850–635 Ma, which may have brought glacial conditions all the way to the equator, resulting in a " Snowball Earth ". The atmosphere of the early Earth is not well understood. Most geologists believe it was composed primarily of nitrogen, carbon dioxide, and other relatively inert gases, and

720-534: The Pennsylvanian Age . The plateau was subjected to glaciation during the Pleistocene ice age . As a result, the topography of this section of the plateau is relatively flat in comparison to the rest of the physiographic province. This portion of the plateau is marked with evidence of a glaciated past including bogs , lakes, and small hills of sand and gravel. The topography of the rest of the plateau

768-522: The geologic time scale . It spans from the formation of Earth about 4.6 billion years ago ( Ga ) to the beginning of the Cambrian Period, about 538.8 million years ago ( Ma ), when hard-shelled creatures first appeared in abundance. Relatively little is known about the Precambrian, despite it making up roughly seven-eighths of the Earth's history , and what is known has largely been discovered from

816-482: The oxygen catastrophe . At first, oxygen would have quickly combined with other elements in Earth's crust, primarily iron, removing it from the atmosphere. After the supply of oxidizable surfaces ran out, oxygen would have begun to accumulate in the atmosphere, and the modern high-oxygen atmosphere would have developed. Evidence for this lies in older rocks that contain massive banded iron formations that were laid down as iron oxides. A terminology has evolved covering

864-401: The 1960s onwards. The Precambrian fossil record is poorer than that of the succeeding Phanerozoic , and fossils from the Precambrian (e.g. stromatolites ) are of limited biostratigraphic use. This is because many Precambrian rocks have been heavily metamorphosed , obscuring their origins, while others have been destroyed by erosion, or remain deeply buried beneath Phanerozoic strata. It

912-654: The Appalachia region. Abundant mushroom and lichen can be found including chanterelle , oyster mushroom and rock tripe . The Appalachian Plateau has a vast array of natural resources throughout its rugged landscape. Within these resources, there are many sedimentary substances. In the valleys of the Appalachian Plateau there is an abundance of limestone . This limestone is still mined for cement and aggregate. Due to excessive mining over time, limestone fields are depleted in many areas but some are still relatively plentiful. Ironstone and coal are also among

960-482: The Appalachian Plateau falls under the classification of Appalachian Highlands because of those similar characteristics. The rock underlying the Appalachian Plateau consists of a base of Precambrian rock, overlain by sedimentary rock from the Paleozoic Era . On top of the basement is a thick layer, approximately 20,000 feet, of a mixture of Cambrian , Ordovician , and Middle Silurian rock. This rock consists of shale , siltstone , and sandstone . Above this layer

1008-428: The Appalachian Plateau region great biodiversity. To the north are many conifers, such as red spruce and balsam fir which can be seen growing at the northernmost latitudes of the Appalachian region. In the northern sections of the plateau at lower elevations you can find northern hardwoods , such as sugar maple and white oak . In southern Appalachia, growth of sycamore , walnut , and hickory trees are common. It

SECTION 20

#1732773105878

1056-645: The Appalachian Plateau region include the Southern Appalachian Forest Coalition and the Northern Forest Alliance. Ultimately, experts and researchers say the best way to continue protecting the Appalachian region is to incorporate conservation into public education so that people understand and support the benefits of conserving the lands. The Appalachian region is home to a wide variety of plant and animal life due to its vast array of climate and conditions giving

1104-472: The Appalachian region but have vanished. Elk have been reintroduced in some regions, having died out due to overhunting and habitat destruction previously. Throughout all of the Appalachian Plateau region there is an abundance of fox, raccoon, wild boar, black bears, white-tailed deer, and beaver. Researchers also found there to be over 200 species of game and songbirds including wild turkey, heron, geese, hawks, ducks and many more. Fungi are also prominent in

1152-512: The Appalachian region's forest was at full-scale with the invention of the railroad, saw-mills, and clear-cutting of trees. This caused major flooding and wildfires to the region and destroyed keystone species across the region. Realizing that the destruction of the forest was becoming a major issue, the government passed the Weeks Act of 1911, which allowed the federal government to purchase private land in order to protect rivers and watersheds in

1200-595: The Europeans arrived in North America. Europeans settled in North America beginning in the seventeenth century. In 1749, Jacob Martin and Steven Sewell were the first Europeans known to settle the Appalachian Plateau, specifically in what is now Pocahontas County, West Virginia . European colonization and competition with the Native Americans resulted in high mortality due to new diseases, as well as more deaths and social disruption due to warfare. After pushing out

1248-565: The Native Americans, the European American settlers developed much of this land for agriculture. From 1861 to 1865, the Appalachian Plateau suffered from the American Civil War , but in comparison to many other parts of the country, little damage was done. During the war, Union forces gained control over a majority of the plateau, and afterwards that possession was not challenged. Only three noteworthy battles occurred in

1296-507: The United States lived in the Appalachian region more than 12,000 years ago; however, it is hard to say exactly when the occupants first inhabited the land. Human artifacts were collected near the Meadowcroft Rockshelter in southern Pennsylvania that were at least 16,000 years old. Because the early Native Americans were hunter-gatherers living off the land, they left little material traces of their lives behind them. This

1344-769: The United States, the Blue Mountains and Hornsby Plateau in Australia and the Deccan Plateau in India are examples of dissected plateaus formed after regional uplift. These older uplifts have been eroded by creeks and rivers to develop steep relief not immediately distinguishable from mountains . Many areas of the Allegheny Plateau and the Cumberland Plateau, which are at

1392-545: The United States. The Appalachian Plateau is a province of the physiographic region of the Appalachian Highlands . The Appalachian Plateau province is divided into seven physiographic sections: Mohawk, Catskill , Southern New York , Allegheny Mountains , Kanawha , Cumberland Plateau , and the Cumberland Mountains . Each section is classified under the Appalachian Plateau province because of its similarities in geologic makeup, topography, and wildlife. Likewise,

1440-401: The current scheme based upon numerical ages. Such a system could rely on events in the stratigraphic record and be demarcated by GSSPs . The Precambrian could be divided into five "natural" eons, characterized as follows: The movement of Earth's plates has caused the formation and break-up of continents over time, including occasional formation of a supercontinent containing most or all of

1488-453: The early years of the Earth's existence, as radiometric dating has allowed absolute dates to be assigned to specific formations and features. The Precambrian is divided into three eons: the Hadean (4567.3–4031 Ma), Archean (4031-2500 Ma) and Proterozoic (2500-538.8 Ma). See Timetable of the Precambrian . It has been proposed that the Precambrian should be divided into eons and eras that reflect stages of planetary evolution, rather than

Appalachian Plateau - Misplaced Pages Continue

1536-706: The eastern United States. The first purchase under this act was the Pisgah National Forest . In 1964, the Wilderness Act expanded protections for millions of acres of federal land, such as the Shining Rock and Linville Gorge . The 1975 Eastern Wilderness Act created expanded protected areas in North Carolina, Virginia, and Tennessee. Today, close to 21% of the region is protected. Conservation groups that are dedicated to preserving

1584-400: The edge of the plateau; there are many more state parks and state forests throughout the region, and Wayne National Forest and Allegheny National Forest lie on the Appalachian plateau as well. 40°N 78°W  /  40°N 78°W  / 40; -78 Dissected plateau A dissected plateau may also be formed, or created, usually on a comparatively small scale, by

1632-705: The end of that time span, marking the beginning of the Phanerozoic Eon. By the middle of the following Cambrian Period, a very diverse fauna is recorded in the Burgess Shale , including some which may represent stem groups of modern taxa. The increase in diversity of lifeforms during the early Cambrian is called the Cambrian explosion of life. While land seems to have been devoid of plants and animals, cyanobacteria and other microbes formed prokaryotic mats that covered terrestrial areas. Tracks from an animal with leg-like appendages have been found in what

1680-596: The highest peaks located in the Cumberland Mountains. A physiographic region is a large portion of land that is grouped by several factors. Each region has similar geology, topography , and groups of plants and animals. There are eight physiographic regions in the United States . Each region is divided into provinces, there are 25 provinces in the United States. Each region is then divided into sections, creating 85 different physiographic sections in

1728-541: The landmass. The earliest known supercontinent was Vaalbara . It formed from proto-continents and was a supercontinent 3.636 billion years ago. Vaalbara broke up c. 2.845–2.803 Ga ago. The supercontinent Kenorland was formed c. 2.72 Ga ago and then broke sometime after 2.45–2.1 Ga into the proto-continent cratons called Laurentia , Baltica , Yilgarn craton and Kalahari . The supercontinent Columbia , or Nuna, formed 2.1–1.8 billion years ago and broke up about 1.3–1.2 billion years ago. The supercontinent Rodinia

1776-406: The levelling of terrain by planing and deposition beneath an ice sheet or perhaps, an ice cap . Subsequently, during the same or a later glacial , the margins of the glacial till plain are removed by glaciers , leaving the plateau into which erosion by water incises valleys . Such a plateau may be level or gently sloping but may be distinguished by the till caps on its hills. Glacial till

1824-592: The mines. Among the terrible coal incidents was the Monongah mining disaster of 1907. Protecting the Appalachian Region from damage of human influence has been important in the modern era. Conservationists have been fighting to preserve the wildlife in the Appalachia region . The region has proved that with good care, the flora and fauna can be very resilient. However, back in 1890, the destruction of

1872-614: The plateau appears as a mountain range. This false appearance is due to a very steep slope on the eastern side known as the Allegheny Front . The eastern edge is the highest part of the Appalachian Plateau. In Pennsylvania , the elevation ranges from 1,750 to 3,000 feet and continues to rise toward West Virginia , where the elevation is around 4,800 feet. From West Virginia to Tennessee , the elevation lowers to 3,000 feet and continues slanting downward to 1,000 feet in Alabama . On

1920-413: The plateau region during the war, so not much of the land was destroyed. After the war, the coal industry boomed. Many counties in the Appalachian Plateau region, such as McDowell County, West Virginia , became dominated by coal mining. Coal mining towns were created, and many immigrants were attracted to the region for work. Although mining was good for the economy, deaths were high in the harsh work of

1968-445: The plentiful natural resources found. In different regions of the Appalachian Plateau, enough plant debris accumulated to form peat, which upon burial, compaction and heating was made into the coal of the Appalachian coalfields. Due to the abundant coal in the Appalachian Plateau, coal mining has been a staple of the area and has proved to be a very successful mining hub. Iron ore was once an extremely abundant natural resource but due to

Appalachian Plateau - Misplaced Pages Continue

2016-526: The same area. However, there is evidence that life could have evolved over 4.280 billion years ago. There is a fairly solid record of bacterial life throughout the remainder (Proterozoic Eon) of the Precambrian. Complex multicellular organisms may have appeared as early as 2100 Ma. However, the interpretation of ancient fossils is problematic, and "... some definitions of multicellularity encompass everything from simple bacterial colonies to badgers." Other possible early complex multicellular organisms include

2064-1039: The thin layer of iron, over time it was mostly depleted. A very well-known natural resource of the Appalachian Plateau is its land and soil. The soil is rich and it is ideal for farmland. Within the limestone found throughout the Appalachian Plateau there are many fossilized substances such as old plant and stems, which may help to explain why the plateau also has a rich amount of natural gases and petroleum. The Appalachian Plateau has many landmarks and public spaces to camp out, go hiking, and sight see. Allegany State Park in New York, Ohiopyle State Park in Pennsylvania, Hocking Hills State Park in Ohio, Cooper's Rock State Forest in West Virginia, and Cloudland Canyon State Park in Georgia are notable state parks on or along

2112-594: The western edge of the Appalachian Mountains of eastern North America , are called "mountains" but are actually dissected plateaus. One can stand on the top of one of these high "mountains" and note that all the other tops are nearly the same height, which represents the original elevation profile of the plain before uplift, and thereafter the subsequent weather erosion. Precambrian The Precambrian ( / p r i ˈ k æ m b r i . ə n , - ˈ k eɪ m -/ pree- KAM -bree-ən, -⁠KAYM- ; or Pre-Cambrian , sometimes abbreviated pC , or Cryptozoic )

2160-506: The western side of the plateau, the elevation is 900 feet in Ohio , increasing to about 2,000 feet in Kentucky . From Kentucky the elevation drops down to 500 feet in northwestern Alabama . The plateau has a slight slant towards the northwest, making it higher on the eastern side. A large portion of the plateau is a coalfield, which was formed approximately 320 million years ago during

2208-621: Was created mainly from stream erosion . The result is a rugged landscape, unlike many other plateaus, that includes many narrow stream valleys surrounded by steep ridges. The region in Kentucky is known as the Eastern Kentucky Coalfield . It includes 35 counties and covers around 30% of Kentucky's land. Major sections include the Allegheny Plateau , the Cumberland Plateau and the Cumberland Mountains , with

2256-482: Was lacking in free oxygen . There is, however, evidence that an oxygen-rich atmosphere existed since the early Archean. At present, it is still believed that molecular oxygen was not a significant fraction of Earth's atmosphere until after photosynthetic life forms evolved and began to produce it in large quantities as a byproduct of their metabolism . This radical shift from a chemically inert to an oxidizing atmosphere caused an ecological crisis , sometimes called

2304-852: Was mud 551 million years ago. The RNA world hypothesis asserts that RNA evolved before coded proteins and DNA genomes. During the Hadean Eon (4,567–4,031 Ma) abundant geothermal microenvironments were present that may have had the potential to support the synthesis and replication of RNA and thus possibly the evolution of a primitive life form. It was shown that porous rock systems comprising heated air-water interfaces could allow ribozyme - catalyzed RNA replication of sense and antisense strands that could be followed by strand-dissociation, thus enabling combined synthesis, release and folding of active ribozymes. This primitive RNA replicative system also may have been able to undergo template strand switching during replication ( genetic recombination ) as

#877122