The Iapetus Ocean was an ocean that existed in the Southern Hemisphere between Laurentia (Scotland and North America) and Baltica (Scandinavia) between 400 and 600 million years ago. An ocean (from Greek, ''Okeanos'' (Oceanus) is a major body of saline water, and a principal component of the Hydrosphere. Southern Hemisphere is the half of a Planet that is South of the Equator —the word hemisphere literally means 'half ball' Laurentia (also known as the North American craton) like all Craton land was created as continents moved about the surface of the Earth Scotland ( Gaelic: Alba) is a Country in northwest Europethat occupies the northern third of the island of Great Britain. Baltica redirects here For the Russian beer, see Baltika Breweries Baltica is a name applied by geologists to a late- Proterozoic, Terminology and usage As a cultural term "Scandinavia" has no official definition and is subject to usage by those who identify with the culture in question as well As a sort of precursor of the Atlantic Ocean, it was named for the Titan Iapetus, who in Greek mythology was the father of Atlas. In Greek mythology, the Titans ( Greek: Tītā́n; plural Tītânes) were a race of powerful Deities that ruled during the legendary In Greek mythology, Iapetus, also Iapetos or Japetus (Ἰαπετός was a Titan, the son of Uranus and Gaia, and father Greek mythology is the body of stories belonging to the ancient Greeks concerning their gods and Heroes the nature of the world and the origins and significance In Greek mythology, Atlas (Eng /'æt ləs/ Gk Ἄτλας was the primordial Titan who supported the heavens
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The Iapetus Ocean and the geology of North America
The Taconic orogeny
The Taconic orogeny was a great mountain building period that perhaps had the greatest overall effect on the geologic structure of basement rocks within the New York Bight region. The Taconic orogeny was a great mountain building period that perhaps had the greatest overall effect on the geologic structure of basement rocks within the New York Bight The New York Bight is a large gulf on the Atlantic Ocean along the coast of North America in the northeastern United States. The effects of this orogeny are most apparent throughout New England, but the sediments derived from mountainous areas formed in the northeast can be traced throughout the Appalachian and Midcontinent regions of North America. History See also History of New England New England's earliest inhabitants were Algonquian -speaking Native Americans including the The following discussion provides a summary of events leading to the culmination of this orogeny.
Beginning in Cambrian times (about 550 million years ago) the Iapetus Ocean began to grow progressively narrower. The Cambrian is a geologic period and system that began about Ma (million years ago at the end of the Proterozoic eon and ended about Ma with The weight of accumulating sediments, in addition to compressional forces in the crust, forced the eastern edge of the North American continent to gradually fold downward. In this manner, shallow carbonate deposition that had persisted on the shelf margin through Late Cambrian into Early Ordovician time, gave way to fine-grained clastic deposition and deeper water conditions during the Middle Ordovician. The Furongian (which represented approximately the old notions of Late Cambrian, Merioneth, Croixian, or Potsdamian) is the third and final The Early Ordovician, also called the Lower Ordovician by Geologists is the first subdivision of the Ordovician period and marked a great diversification The Middle Ordovician (from 472 to 461 million years ago) is the second subdivision of the Ordovician period Sometime during this period a convergent plate boundary developed along the eastern edge of a small island chain. Crustal material beneath the Iapetus Ocean sank into the mantle along a subduction zone with an eastward-dipping-orientation. In Geology, a subduction zone is an area on Earth where two tectonic plates meet and move towards one another with one sliding underneath the other Partial melting of the down-going plate produced magma that returned to the surface to form the Taconic island arc offshore from the continent. By the Late Ordovician, this island arc had collided with the North American continent. The Late Ordovician, also called the Upper Ordovician by Geologists is the third epoch of the Ordovician period The sedimentary and igneous rock between the land masses were intensely folded and faulted, and were subjected to varying degrees of intense metamorphism. Sedimentary rock is one of the three main rock types (the others being igneous and Metamorphic rock) Igneous rocks (etymology from Latin ignis, fire are rocks formed by solidification of cooled Magma (molten rock Metamorphism can be defined as the solid state recrystallisation of pre-existing rocks due to changes in heat and/or pressure and/or introduction of fluids i This was the final episode of the long-lasting mountain-building period referred to as the Taconic Orogeny. A mountain is a Landform that extends above the surrounding Terrain in a limited area with a peak
When the Taconic Orogeny subsided in the New York Bight region during Late Ordovician time (about 440 million years ago), subduction ended, culminating in the accretion of the Iapetus Terrane onto the eastern margin of the continent. This resulted in the formation of a great mountain range throughout New England and eastern Canada, and perhaps to a lesser degree, southward along the region that is now the Piedmont of eastern North America. The newly expanded continental margin gradually stabilized. The continental margin is the zone of the Ocean floor that separates the thin Oceanic crust from thick Continental crust. Erosion continued to strip away sediments from upland areas. Inland seas covering the Midcontinent gradually expanded eastward into the New York Bight region and became the site of shallow clastic and carbonate deposition. This tectonically-quiet period persisted until the Late Devonian time (about 360 million years ago) when the next period of mountain-building began, the Acadian Orogeny. The Acadian orogeny is a middle Paleozoic deformation especially in the northern Appalachians, between New York and Newfoundland.
The Acadian orogeny
The Acadian orogeny is the name of a long-lasting mountain building disturbance that most greatly affected the Northern Appalachian region (New England northeastward into the Gaspé region of Canada). The Appalachian Mountains ( often called the Appalachians, are a vast system of mountains in eastern North America. The "climax" of this orogeny is dated as early in the Late Devonian, but deformation, plutonism, and metamorphism related to this orogeny continued well into the Mississippian Period. The cause of this great period of deformation is a result of the plate-docking of a small continental landmass called Avalonia (named after the Avalon Peninsula of Newfoundland). Avalonia was an ancient Microcontinent or Terrane whose history formed much of the older rocks of Western Europe, Atlantic Canada and parts of the The Avalon Peninsula is a large Peninsula (10360 km²) that makes up the southeast portion of the island of Newfoundland. The docking of Avalonia onto the margin of Laurentia resulted in the closing of a portion of the Iapetus Ocean. The Acadian Orogeny spanned a period of about 50 million years (beginning roughly 375 million years ago). During the course of the orogeny, older rocks were deformed and metamorphosed, and new faults formed and older faults were reactivated.
Avalonia was gradually torn apart as plate tectonic forces accreted the landmass onto the edge of the larger North American continent. Today, portions of the ancient Avalonia landmass occur in scattered outcrop belts along the eastern margin of North America. One belt occurs in Newfoundland, another forms the bedrock of much of eastern Massachusetts.
The Iapetus Ocean and the geology of the British Isles
Formation
Iapetus Ocean, along with its sister ocean, Khanty Ocean, formed when the supercontinent of Proto-Laurasia rifted into three separate continents - Baltica, Laurentia, and Siberia. Khanty Ocean was an ancient small ocean that existed near the end of the Precambrian time to the Silurian. Baltica redirects here For the Russian beer, see Baltika Breweries Baltica is a name applied by geologists to a late- Proterozoic, Laurentia (also known as the North American craton) like all Craton land was created as continents moved about the surface of the Earth Siberia is the Craton located in the heart of the region of Siberia. The ocean was situated between Laurentia and Baltica.
See also
- Avalonia
- Baltica
- London-Brabant Island
- Plate tectonics
- Geologic timescale
- Southern uplands of Scotland
- Khanty Ocean
External links
Note: some material in this article has been adapted from public domain USGS material at http://3dparks.wr.usgs.gov/nyc/valleyandridge/valleyandridge.htm and http://3dparks.wr.usgs.gov/nyc/highlands/highlands.html
Avalonia was an ancient Microcontinent or Terrane whose history formed much of the older rocks of Western Europe, Atlantic Canada and parts of the Baltica redirects here For the Russian beer, see Baltika Breweries Baltica is a name applied by geologists to a late- Proterozoic, The London-Brabant Island goes under a number of names such as London Island, London Platform, London-Brabant Massif, Wales-Brabant Massif Plate tectonics (from Greek τέκτων tektōn "builder" or "mason" describes the large scale motions of Earth 's Lithosphere The geologic time scale is a chronologic schema (or idealized Model) relating Stratigraphy to time that is used by Geologists and other The Southern Uplands is the southernmost of Scotland 's three major geographic areas (the others being the Central Belt and the Highlands) Khanty Ocean was an ancient small ocean that existed near the end of the Precambrian time to the Silurian.Dapyx Software network: MP3 Explorer | Ebook Manager | Zenithic