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Al Hajar Mountains
The Hajar Mountains (, ''The Rocky Mountains'' or ''The Stone Mountains'') are one of the highest mountain ranges in the Arabian Peninsula, shared between northern Oman and eastern United Arab Emirates. Also known as "Oman Mountains", they separate the low coastal plain of Oman from the high desert plateau, and lie inland from the Gulf of Oman. ''Al'' () means "the", and ''Ḥajar'' () means "stone" or "rock". So ''al-Ḥajar'' () is named as "the stone" or "the rock". Geology Orography and tectonic setting The Hajar Mountains extend for through the UAE and Oman. They are located on the north-east corner of the Arabian Plate, reaching from the Musandam Peninsula through to the east coast of Oman. The range is about wide, with Jabal Shams being the highest peak at in the central region of the mountains. Currently, the Arabian Plate is moving north relative to the Eurasian Plate at per year. Continental collision is occurring at the Zagros fold and thrust belt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Hajar
Central is an adjective usually referring to being in the center of some place or (mathematical) object. Central may also refer to: Directions and generalised locations * Central Africa, a region in the centre of Africa continent, also known as Middle Africa * Central America, a region in the centre of America continent * Central Asia, a region in the centre of Eurasian continent * Central Australia, a region of the Australian continent * Central Belt, an area in the centre of Scotland * Central Europe, a region of the European continent * Central London, the centre of London * Central Region (other) * Central United States, a region of the United States of America Specific locations Countries * Central African Republic, a country in Africa States and provinces * Blue Nile (state) or Central, a state in Sudan * Central Department, Paraguay * Central Province (Kenya) * Central Province (Papua New Guinea) * Central Province (Solomon Islands) * Central Province, Sri La ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maastrichtian
The Maastrichtian ( ) is, in the International Commission on Stratigraphy (ICS) geologic timescale, the latest age (geology), age (uppermost stage (stratigraphy), stage) of the Late Cretaceous epoch (geology), Epoch or Upper Cretaceous series (stratigraphy), Series, the Cretaceous geologic period, Period or system (stratigraphy), System, and of the Mesozoic geologic era, Era or Erathem. It spanned the interval from . The Maastrichtian was preceded by the Campanian and succeeded by the Danian (part of the Paleogene and Paleocene). It is named after the city of Maastricht, the capital and largest city of the Limburg (Netherlands), Limburg province in the Netherlands. The Cretaceous–Paleogene extinction event (formerly known as the Cretaceous–Tertiary period, Tertiary extinction event) occurred at the end of this age. In this extinction event, mass extinction, many commonly recognized groups such as non-avian dinosaurs, plesiosaurs and mosasaurs, as well as many other lesser-kn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samail Ophiolite
The Samail Ophiolite, also known as the Semail Ophiolite, is a large, ancient geological formation in Oman and the United Arab Emirates in the Arabian Peninsula. It is one of the world's largest and best-exposed segments of oceanic crust, made of volcanic rocks and ultramafic rocks from the Earth's upper mantle that was overthrust onto the continental crust. This ophiolite provides insight into the dynamics of oceanic crust formation and the tectonic processes involved in the creation of Oceanic basin, ocean basins. Formed during the Late Cretaceous period, approximately 95 million years ago, the Samail Ophiolite represents a fragment of the Tethys Ocean, Tethyan Oceanic crust that was thrust over continental crust due to the convergence of the African and Eurasian tectonic plates. This geological phenomenon, known as obduction, makes it a site for studying the processes of oceanic crust formation, subduction, and obduction. It covers an area of around 100,000 square kilometers, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australian Plate
The Australian plate is or was a major tectonic plate in the eastern and, largely, southern hemispheres. Originally a part of the ancient continent of Gondwana, Australia remained connected to India and Antarctica until approximately when India broke away and began moving north. Australia and Antarctica had begun rifting by and completely separated a while after this, some believing as recently as , but most accepting presently that this had occurred by . The Australian plate later fused with the adjacent Indian plate beneath the Indian Ocean to form a single Indo-Australian plate. However, recent studies suggest that the two plates may have once again split apart and have been separate plates for at least 3 million years. The Australian plate includes the continent of Australia, including Tasmania, as well as portions of New Guinea, New Zealand and the Indian Ocean basin. Scope The continental crust of this plate covers the whole of Australia, the Gulf of Carpentaria, sou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gondwana
Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zealandia, Arabian Peninsula, Arabia, and the Indian subcontinent. Gondwana was formed by the Accretion (geology), accretion of several cratons (large stable blocks of the Earth's crust), beginning with the East African Orogeny, the collision of India and Geography of Madagascar, Madagascar with East Africa, and culminating in with the overlapping Brasiliano orogeny, Brasiliano and Kuunga orogeny, Kuunga orogenies, the collision of South America with Africa, and the addition of Australia and Antarctica, respectively. Eventually, Gondwana became the largest piece of continental crust of the Paleozoic Era, covering an area of some , about one-fifth of the Earth's surface. It fused with Laurasia during the Carboniferous to form Pan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tethys Ocean
The Tethys Ocean ( ; ), also called the Tethys Sea or the Neo-Tethys, was a prehistoric ocean during much of the Mesozoic Era and early-mid Cenozoic Era. It was the predecessor to the modern Indian Ocean, the Mediterranean Sea, and the Eurasian inland marine basins (primarily represented today by the Black Sea and Caspian Sea). During the early Mesozoic, as Pangaea broke up, the Tethys Ocean was defined as the ocean located between the ancient continents of Gondwana and Laurasia. After the opening of the Indian and Atlantic oceans during the Cretaceous Period and the breakup of these continents over the same period, it came to be defined as the ocean bordered by the continents of Africa, Eurasia, India, and Australasia. During the early-mid Cenozoic, the Indian, African, Australian and Arabian plates moved north and collided with the Eurasian plate, which created new borders to the ocean, a land barrier to the flow of currents between the Indian and Mediterranean basins, and t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountain Formation
Mountain formation occurs due to a variety of geological processes associated with large-scale movements of the Earth's crust ( tectonic plates). Folding, faulting, volcanic activity, igneous intrusion and metamorphism can all be parts of the orogenic process of mountain building. The formation of mountains is not necessarily related to the geological structures found on it. From the late 18th century until its replacement by plate tectonics in the 1960s, geosyncline theory was used to explain much mountain-building. The understanding of specific landscape features in terms of the underlying tectonic processes is called '' tectonic geomorphology'', and the study of geologically young or ongoing processes is called '' neotectonics''. Types of mountains There are five main types of mountains: volcanic, fold, plateau, fault-block, and dome. A more detailed classification useful on a local scale predates plate tectonics and adds to these categories. Volcanic mountains Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Makran Trench
The Makran Trench is the physiographic expression of a subduction zone along the northeastern margin of the Gulf of Oman adjacent to the southwestern coast of Balochistan of Pakistan and the southeastern coast of Iran. In this region the oceanic crust of the Arabian plate is being subducted beneath the continental crust of the Eurasian plate. Tectonics In the Makran region, the Arabian plate subducts beneath the Eurasian plate at ~2-4cm/yr. This subduction is associated with an accretionary wedge of sediments which has developed since the Cenozoic. To the west, the Makran Trench is connected by the Minab Fault system to the Zagros fold and thrust belt. To the east, the Makran Trench is bounded by the transpressional strike-slip Ornach-Nal and Chaman Faults, which connect to the Himalayan orogeny. The Makran Subduction Zone is often split into two segments: the east and west. The Sonne fault divides the two. Though largely much quieter than many other subduction zo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanic Crust
Oceanic crust is the uppermost layer of the oceanic portion of the tectonic plates. It is composed of the upper oceanic crust, with pillow lavas and a dike complex, and the lower oceanic crust, composed of troctolite, gabbro and ultramafic cumulates. The crust lies above the rigid uppermost layer of the mantle. The crust and the rigid upper mantle layer together constitute oceanic lithosphere. Oceanic crust is primarily composed of mafic rocks, or sima, which is rich in iron and magnesium. It is thinner than continental crust, or sial, generally less than 10 kilometers thick; however, it is denser, having a mean density of about 3.0 grams per cubic centimeter as opposed to continental crust which has a density of about 2.7 grams per cubic centimeter. The crust uppermost is the result of the cooling of magma derived from mantle material below the plate. The magma is injected into the spreading center, which consists mainly of a partly solidified crystal mush derive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subduction
Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second plate, the heavier plate dives beneath the other and sinks into the mantle. A region where this process occurs is known as a subduction zone, and its surface expression is known as an arc-trench complex. The process of subduction has created most of the Earth's continental crust. Rates of subduction are typically measured in centimeters per year, with rates of convergence as high as 11 cm/year. Subduction is possible because the cold and rigid oceanic lithosphere is slightly denser than the underlying asthenosphere, the hot, ductile layer in the upper mantle. Once initiated, stable subduction is driven mostly by the negative buoyancy of the dense subducting lithosphere. The down-going slab sinks into the mantle largely under its own ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zagros Fold And Thrust Belt
The Zagros fold and thrust belt (Zagros FTB) is an approximately long zone of deformed crustal rocks, formed in the foreland of the collision between the Arabian plate and the Eurasian plate. It is host to one of the world's largest petroleum provinces, containing about 49% of the established hydrocarbon reserves in fold and thrust belts (FTBs) and about 7% of all reserves globally. Plate tectonic setting The Zagros FTB is formed along a section of the plate boundary that is subject to oblique convergence with the Arabian plate moving northwards with respect to the Eurasian plate at about 3 cm per year. The degree of obliqueness reduces southwards along the Zagros, with the collision becoming near orthogonal within the Fars domain. The relative movement between the plates is only partly taken up within the Zagros, the remainder is taken up by deformation in the Alborz mountains and the Lesser Caucasus Mountains to the north of the Iranian plateau and along the zone f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
