The Moroccan Meseta or Western Meseta [1] is an uplifted terrane of dominantly Palaeozoic rocks exposed along the Moroccan coastal block between the Atlantic Margin and the Middle Atlas. [2] [3] [4]
The Moroccan Meseta or Western Meseta [1] is an uplifted terrane of dominantly Palaeozoic rocks exposed along the Moroccan coastal block between the Atlantic Margin and the Middle Atlas. [2] [3] [4]
The Meseta Domain, taking its name from Spain's Meseta Central inner plateau, is an area of stable Paleozoic rock that was never affected by the Hercynian orogeny and was later covered by Mesozoic and Cenozoic sedimentary rocks. Forming Morocco's Central Massif, the Meseta Domain completely conceals Precambrian rocks, although boreholes have found Neoproterozoic rocks in a Meseta anticline. The domain is split in two by the Middle Atlas fold belt. The Western Meseta has relatively little sedimentary cover and well-developed massifs, while the Eastern Meseta spanning the border with Algeria has numerous, small Paleozoic massifs. Continuing from the Neoproterozoic until the Middle Devonian, western Morocco and the Anti-Atlas had the same depositional environment—molasse redbed deposition and post-orogeny volcanism. Southern Morocco was flooded by a massive shallow marine shelf, building up significant carbonates, mixed with continental sediments pouring in from inland areas now in the Sahara. In the Late Devonian, western Morocco and the Anti-Atlas split up into fault-bounded basins, which deformed during the Hercynian orogeny. [5]
 | This section is empty. You can help by adding to it. (December 2019) |
The geology of the Appalachians dates back more than 1.1 billion years to the Mesoproterozoic era when two continental cratons collided to form the supercontinent Rodinia, 500 million years prior to the later development of the range during the formation of the supercontinent Pangea. The rocks exposed in today's Appalachian Mountains reveal elongate belts of folded and thrust faulted marine sedimentary rocks, volcanic rocks and slivers of ancient ocean floor – strong evidence that these rocks were deformed during plate collision. The birth of the Appalachian ranges marks the first of several mountain building plate collisions that culminated in the construction of the supercontinent Pangea with the Appalachians and neighboring Anti-Atlas mountains near the center. These mountain ranges likely once reached elevations similar to those of the Alps and the Rocky Mountains before they were eroded.
The Variscan or Hercynianorogeny was a geologic mountain-building event caused by Late Paleozoic continental collision between Euramerica (Laurussia) and Gondwana to form the supercontinent of Pangaea.
The Rhenohercynian Zone or Rheno-Hercynian zone in structural geology describes a fold belt of west and central Europe, formed during the Hercynian orogeny. The zone consists of folded and thrust Devonian and early Carboniferous sedimentary rocks that were deposited in a back-arc basin along the southern margin of the then existing paleocontinent Laurussia.
The Saxothuringian Zone, Saxo-Thuringian zone or Saxothuringicum is in geology a structural or tectonic zone in the Hercynian or Variscan orogen of central and western Europe. Because rocks of Hercynian age are in most places covered by younger strata, the zone is not everywhere visible at the surface. Places where it crops out are the northern Bohemian Massif, the Spessart, the Odenwald, the northern parts of the Black Forest and Vosges and the southern part of the Taunus. West of the Vosges terranes on both sides of the English Channel are also seen as part of the zone, for example the Lizard complex in Cornwall or the Léon Zone of the Armorican Massif (Brittany).
The Mid-German Crystalline High is a structural high in the Paleozoic geology of Germany. The high forms a northeast-southwest oriented zone through Germany, but actual rock outcrops are sparse since Paleozoic basement rocks are in most of central Germany overlain by younger sedimentary rocks. The Mid-German Crystalline High crops out in the Odenwald, the Spessart, the northern Vosges and some small other massifs.
The Massif Central is one of the two large basement massifs in France, the other being the Armorican Massif. The Massif Central's geological evolution started in the late Neoproterozoic and continues to this day. It has been shaped mainly by the Caledonian orogeny and the Variscan orogeny. The Alpine orogeny has also left its imprints, probably causing the important Cenozoic volcanism. The Massif Central has a very long geological history, underlined by zircon ages dating back into the Archaean 3 billion years ago. Structurally it consists mainly of stacked metamorphic basement nappes.
The main points that are discussed in the geology of Iran include the study of the geological and structural units or zones; stratigraphy; magmatism and igneous rocks; ophiolite series and ultramafic rocks; and orogenic events in Iran.
The geology of Germany is heavily influenced by several phases of orogeny in the Paleozoic and the Cenozoic, by sedimentation in shelf seas and epicontinental seas and on plains in the Permian and Mesozoic as well as by the Quaternary glaciations.
The geology of Western Sahara includes rock units dating back to the Archean more than two billion years old, although deposits of phosphorus formed in the Mesozoic and Cenozoic have helped to prompt the current Moroccan occupation of most of the country.
The geology of Guinea-Bissau is oldest in the east and becomes younger toward the west, with sediments from the past 66 million years nearer the coast. Some rock units in the northeast are as much as 680 million years old and throughout the geologic past Guinea-Bissau was influenced by the Mauritanide Belt orogeny and was submerged or partially submerged as a marine shelf or river delta for most of its existence.
The geology of Mauritania is built on more than two billion year old Archean crystalline basement rock in the Reguibat Shield of the West African Craton, a section of ancient and stable continental crust. Mobile belts and the large Taoudeni Basin formed and filled with sediments in the connection with the Pan-African orogeny mountain building event 600 million years ago and a subsequent orogeny created the Mauritanide Belt. In the last 251 million years, Mauritania has accumulated additional sedimentary rocks during periods of marine transgression and sea level retreat. The arid country is 50% covered in sand dunes and has extensive mineral resources, although iron plays the most important role in the economy.
The geology of Niger comprises very ancient igneous and metamorphic crystalline basement rocks in the west, more than 2.2 billion years old formed in the late Archean and Proterozoic eons of the Precambrian. The Volta Basin, Air Massif and the Iullemeden Basin began to form in the Neoproterozoic and Paleozoic, along with numerous ring complexes, as the region experienced events such as glaciation and the Pan-African orogeny. Today, Niger has extensive mineral resources due to complex mineralization and laterite weathering including uranium, molybdenum, iron, coal, silver, nickel, cobalt and other resources.
The geology of Morocco formed beginning up to two billion years ago, in the Paleoproterozoic and potentially even earlier. It was affected by the Pan-African orogeny, although the later Hercynian orogeny produced fewer changes and left the Maseta Domain, a large area of remnant Paleozoic massifs. During the Paleozoic, extensive sedimentary deposits preserved marine fossils. Throughout the Mesozoic, the rifting apart of Pangaea to form the Atlantic Ocean created basins and fault blocks, which were blanketed in terrestrial and marine sediments—particularly as a major marine transgression flooded much of the region. In the Cenozoic, a microcontinent covered in sedimentary rocks from the Triassic and Cretaceous collided with northern Morocco, forming the Rif region. Morocco has extensive phosphate and salt reserves, as well as resources such as lead, zinc, copper and silver.
The geology of Ohio formed beginning more than one billion years ago in the Proterozoic eon of the Precambrian. The igneous and metamorphic crystalline basement rock is poorly understood except through deep boreholes and does not outcrop at the surface. The basement rock is divided between the Grenville Province and Superior Province. When the Grenville Province crust collided with Proto-North America, it launched the Grenville orogeny, a major mountain building event. The Grenville mountains eroded, filling in rift basins and Ohio was flooded and periodically exposed as dry land throughout the Paleozoic. In addition to marine carbonates such as limestone and dolomite, large deposits of shale and sandstone formed as subsequent mountain building events such as the Taconic orogeny and Acadian orogeny led to additional sediment deposition. Ohio transitioned to dryland conditions in the Pennsylvanian, forming large coal swamps and the region has been dryland ever since. Until the Pleistocene glaciations erased these features, the landscape was cut with deep stream valleys, which scoured away hundreds of meters of rock leaving little trace of geologic history in the Mesozoic and Cenozoic.
The geology of Ukraine is the regional study of rocks, minerals, tectonics, natural resources and groundwater in Ukraine. The oldest rocks in the region are part of the Ukrainian Shield and formed more than 2.5 billion years ago in the Archean eon of the Precambrian. Extensive tectonic evolution and numerous orogeny mountain-building events fractured the crust into numerous block, horsts, grabens and depressions. Ukraine was intermittently flooded as the crust downwarped during much of the Paleozoic, Mesozoic and early Cenozoic, before the formation of the Alps and Carpathian Mountains defined much of its current topography and tectonics. Ukraine was impacted by the Pleistocene glaciations within the last several hundred thousand years. The country has numerous metal deposits as well as minerals, building stone and high-quality industrial sands.
The geology of Belgium encompasses rocks, minerals and tectonic events stretching back more than 500 million years. Belgium covers an area of about 30,507 square kilometers and was instrumental in the development of geology. The extensive outcrops in Belgium became the standard reference points in stratigraphy as early as the mid-19th century. Some of them are internationally recognized features related to the Carboniferous and the Devonian periods. These rocks were folded by two orogeny mountain building events --the Hercynian orogeny, and Caledonian Orogeny. Paleozoic basement rocks cover much of the country and are overlain by Mesozoic and Cenozoic sediments.
The geology of Montana includes thick sequences of Paleozoic, Mesozoic and Cenozoic sedimentary rocks overlying ancient Archean and Proterozoic crystalline basement rock. Eastern Montana has considerable oil and gas resources, while the uplifted Rocky Mountains in the west, which resulted from the Laramide orogeny and other tectonic events have locations with metal ore.
The geology of the Czech Republic is very tectonically complex, split between the Western Carpathian Mountains and the Bohemian Massif.
The geology of Iraq includes thick sequences of marine and continental sedimentary rocks over poorly understood basement rock, at the junction of the Arabian Plate, the Anatolian Plate, and the Iranian Plate.
The geology of Peru includes ancient Proterozoic rocks, Paleozoic and Mesozoic volcanic and sedimentary rocks, and numerous basins and the Andes Mountains formed in the Cenozoic.