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Lockport Group
The Lockport Group is a geologic group in the Appalachian Basin and Michigan Basin in the northeastern United States and Canada. This unit makes up the Niagara Escarpment. Its most famous feature is Niagara Falls. The unit outcrops in New York, Ontario, Michigan, Wisconsin, and Illinois. Description The Lockport Group is made up of four formations. From base to top: Gasport Formation, Goat Island Formation, Eramosa Formation and Guelph Formation. The entire unit is composed of dolomite, with the exception of the Gasport which can be limestone, as well as occasional chert nodules. Stratigraphy {{inline citations needed, section, date=July 2024 The Guelph Formation is at the top of the Lockport Group. It has been called the "Vernon Transition Zone" due to thin beds and laminations between carbonates, claystones and evaporates. Its base is delimited by a stromatolite bed. Below the Guelph is the Eramosa Formation. This formation is typically a thinly laminated packstone and g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group (stratigraphy)
In geology, a group is a lithostratigraphy, lithostratigraphic Stratigraphic unit, unit consisting of a series of related Geological formation, formations that have been classified together to form a group. Formations are the fundamental unit of stratigraphy. Groups may sometimes be combined into Supergroup (geology), supergroups. Groups are useful for showing relationships between formations, and they are also useful for small-scale mapping or for studying the stratigraphy of large regions. Geologists exploring a new area have sometimes defined groups when they believe the strata within the groups can be divided into formations during subsequent investigations of the area. It is possible for only some of the strata making up a group to be divided into formations. An example of a group is the Glen Canyon Group, which includes (in ascending order) the Wingate Sandstone, the Moenave Formation, the Kayenta Formation, and the Navajo Sandstone. Each of the formations can be distingui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gasport Formation
The Gasport Formation is a geologic formation in the Appalachian Basin and Michigan Basin. This is one of the reef formations separating the Appalachian Basin from the Michigan Basin and the Ohio Basin. It is a part of the Lockport Group of carbonates. It is the lowest and oldest formation within the Lockport. The Gasport is found in Michigan, New York, Ohio, and Pennsylvania. Outcrops are limited to the area around the Great Lakes. It is part of a large reef structure dating back to the Silurian period. Being part of the Lockport Group it is a feature of the Niagara Escarpment. Description The Gasport represents a period of reef building with the upper Pekin member containing large Stromatolite structures. The lower Gothic Hill member contains Bryozones, corals, and crinoids. The upper Pekin member is a dark grey argillaceous limestone. The texture of the member tends to be grainstone to wackestone Under the Dunham classification (Dunham, 1962Dunham, R.J., 1962. Classif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chert
Chert () is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a precipitation (chemistry), chemical precipitate or a diagenesis, diagenetic replacement, as in petrified wood. Chert is typically composed of the petrified remains of siliceous ooze, the biogenic sediment that covers large areas of the deep ocean floor, and which contains the silicon skeletal remains of diatoms, Dictyochales, silicoflagellates, and radiolarians. Precambrian cherts are notable for the presence of fossil cyanobacteria. In addition to Micropaleontology, microfossils, chert occasionally contains macrofossils. However, some chert is devoid of any fossils. Chert varies greatly in color, from white to black, but is most often found as gray, brown, grayish brown and light green to rusty redW.L. Roberts, T.J. Campbell, G.R. Rapp Jr., ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limestone
Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science), crystal forms of calcium carbonate . Limestone forms when these minerals Precipitation (chemistry), precipitate out of water containing dissolved calcium. This can take place through both biological and nonbiological processes, though biological processes, such as the accumulation of corals and shells in the sea, have likely been more important for the last 540 million years. Limestone often contains fossils which provide scientists with information on ancient environments and on the evolution of life. About 20% to 25% of sedimentary rock is carbonate rock, and most of this is limestone. The remaining carbonate rock is mostly Dolomite (rock), dolomite, a closely related rock, which contains a high percentage of the mineral Dolomite (mine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Illinois
Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its south. Of the fifty U.S. states, Illinois has the List of U.S. states and territories by GDP, fifth-largest gross domestic product (GDP), the List of U.S. states and territories by population, sixth-largest population, and the List of U.S. states and territories by area, 25th-most land area. Its capital city is Springfield, Illinois, Springfield in the center of the state, and the state's largest city is Chicago in the northeast. Present-day Illinois was inhabited by Indigenous peoples of the Americas#History, Indigenous cultures for thousands of years. The French were the first Europeans to arrive, settling near the Mississippi and Illinois River, Illinois rivers in the 17th century Illinois Country, as part of their sprawling colony of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wisconsin
Wisconsin ( ) is a U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest of the United States. It borders Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. With a population of about 6 million and an area of about 65,500 square miles, Wisconsin is the List of U.S. states and territories by population, 20th-largest state by population and the List of U.S. states and territories by area, 23rd-largest by area. It has List of counties in Wisconsin, 72 counties. Its List of municipalities in Wisconsin by population, most populous city is Milwaukee; its List of capitals in the United States, capital and second-most populous city is Madison, Wisconsin, Madison. Other urban areas include Green Bay, Wisconsin, Green Bay, Kenosha, Wisconsin, Kenosha, Racine, Wisconsin, Racine, Eau Claire, Wisconsin, Eau Claire, and the Fox Cities. Geography of Wiscon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michigan
Michigan ( ) is a peninsular U.S. state, state in the Great Lakes region, Great Lakes region of the Upper Midwest, Upper Midwestern United States. It shares water and land boundaries with Minnesota to the northwest, Wisconsin to the west, Indiana and Illinois to the southwest, Ohio to the southeast, and the Canadian Provinces and territories of Canada, province of Ontario to the east, northeast and north. With a population of 10.14 million and an area of , Michigan is the List of U.S. states and territories by population, 10th-largest state by population, the List of U.S. states and territories by area, 11th-largest by area, and the largest by total area east of the Mississippi River.''i.e.'', including water that is part of state territory. Georgia (U.S. state), Georgia is the largest state by land area alone east of the Mississippi and Michigan the second-largest. The state capital is Lansing, Michigan, Lansing, while its most populous city is Detroit. The Metro Detroit r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Outcrop
An outcrop or rocky outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth and other terrestrial planets. Features Outcrops do not cover the majority of the Earth's land surface because in most places the bedrock or superficial deposits are covered by soil and vegetation and cannot be seen or examined closely. However, in places where the overlying cover is removed through erosion or tectonic uplift, the rock may be exposed, or ''crop out''. Such exposure will happen most frequently in areas where erosion is rapid and exceeds the weathering rate such as on steep hillsides, mountain ridges and tops, river banks, and tectonically active areas. In Finland, glacial erosion during the last glacial maximum (ca. 11000 BC), followed by scouring by sea waves, followed by isostatic uplift has produced many smooth coastal and littoral outcrops. Bedrock and superficial deposits may also be exposed at the Earth's surface due to human exca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niagara Falls
Niagara Falls is a group of three waterfalls at the southern end of Niagara Gorge, spanning the Canada–United States border, border between the Provinces and territories of Canada, province of Ontario in Canada and the state of New York (state), New York in the United States. The largest of the three is Horseshoe Falls, which straddles the Canada–United States border, international border of the two countries. It is also known as the Canadian Falls. The smaller American Falls and Bridal Veil Falls (Niagara Falls), Bridal Veil Falls lie within the United States. Bridal Veil Falls is separated from Horseshoe Falls by Goat Island (New York), Goat Island and from American Falls by Luna Island, with both islands situated in New York. Formed by the Niagara River, which drains Lake Erie into Lake Ontario before flowing out to the Atlantic Ocean through the St. Lawrence River, the combined falls have the List of waterfalls by flow rate, highest flow rate of any waterfall in North ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Niagara Escarpment
The Niagara Escarpment is an approximately discontinuous, arc-shaped but generally northward-facing escarpment, or cuesta, in Canada and the United States. The escarpment begins south of Lake Ontario and circumscribes the top of the Great Lakes Basin running from New York (state), New York through Ontario, Upper Peninsula of Michigan, Michigan, and Wisconsin. Notably, the escarpment is the cliff over which the Niagara River plunges at Niagara Falls, for which it is named. The escarpment is a United Nations Educational, Scientific and Cultural Organization, UNESCO World Niagara Escarpment Biosphere Reserve, Biosphere Reserve. The reserve has the oldest forest ecosystem and trees in eastern North America. The escarpment is not a Fault (geology), fault line but the result of unequal erosion. The cliff-forming rock exposed along the escarpment is a belt of limestone and dolomite of the Lockport Formation of Silurian age. The Niagara Escarpment is the most prominent of several es ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group (geology)
In geology, a group is a lithostratigraphic unit consisting of a series of related formations that have been classified together to form a group. Formations are the fundamental unit of stratigraphy. Groups may sometimes be combined into supergroups. Groups are useful for showing relationships between formations, and they are also useful for small-scale mapping or for studying the stratigraphy of large regions. Geologists exploring a new area have sometimes defined groups when they believe the strata within the groups can be divided into formations during subsequent investigations of the area. It is possible for only some of the strata making up a group to be divided into formations. An example of a group is the Glen Canyon Group, which includes (in ascending order) the Wingate Sandstone, the Moenave Formation, the Kayenta Formation, and the Navajo Sandstone. Each of the formations can be distinguished from its neighbor by its lithology, but all were deposited in the same ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michigan Basin
The Michigan Basin is a geologic basin centered on the Lower Peninsula of the U.S. state of Michigan. The feature is represented by a nearly circular pattern of geologic sedimentary strata in the area with a nearly uniform structural dip toward the center of the peninsula. Geology The basin is centered in Gladwin County where the Precambrian basement rocks are deep. Around the margins, such as under Mackinaw City, Michigan, the Precambrian surface is around below the surface. This contour on the basement surface clips the northern part of the Lower Peninsula and continues under Lake Michigan along the west. It crosses the southern counties of Michigan and continues to the north beneath Lake Huron. On the north in the Canadian Shield, which includes the western part of Michigan's Upper Peninsula, Precambrian rocks are exposed at the surface. The eastern margins of Wisconsin along Green Bay are along the margins of the basin, while Precambrian rocks crop out to the west ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
