Education in Asia

Asia

Asia is both the largest and youngest of the Earth’s continents. Most of the Asian continent is included with Europe in the Eurasian Plate, other parts belong to other plates. In the plate tectonic context, the Arabian Peninsula is not included in Asia. See a full list of Asian countries from Countryaah.

Asia has the farthest north a more than 1900-3500 million years old pre-Cambrian continental core, Angara. The bedrock is here exposed in a small area to the north, the Anabar Shield, and in the Aldan Massif to the southeast. The earth’s crust in the rest of the Asian mainland, over three quarters of the continent, has been added over the last 700 million years. years, by the fact that young and old crustal areas have been united with Angara in so-called growth belts.

This growth has not ceased; a continuous new crust is formed by the tectonically and seismically active arc systems in Southeast and East Asia. The plate boundaries are marked here by ocean depths (” deep sea trenches “)”), where oceanic lithosphere plate sinks in and into the so-called subduction zones is lowered below the island arcs to a depth of 650-700 km. It is the tectonic and magmatic processes in these zones that produce new continental crust; this is done partly by scraping and adding material stacked up in a thick fringe in front of the island arches, and partly by magma rising under the island arcs solidifying as deep rocks or volcanic lava and ash. Continent growth also occurs by seabed dispersal and plate movements carrying “fragments” of old continental crust from a continent Contemporary seabed dispersal south of Australia is thus leading this continent on a collision course towards Timor and other islands in Indonesia, and Australia is therefore expected to be united with Asia someday – just like New Guinea, which is now being pushed into eastern Indonesia from the east.

The older growth belts of mainland Asia also developed plate tectonics, and as they formed, shifting plate movements carried Asia around the globe. When the Baikal calids were added for 700-540 million. years ago, Angara was at 20 ° -40 ° s.br. and collided here with a leading arch system. The next growth belt, the Altaids, was added when Asia, during its operation, reached north of the equator. The Altaids are built of earlier arch systems, which were united with Asia during the Paleozoic up to the Younger Carboniferous. Their very complicated structures are due to the fact that the island arches got pinched when they were added to Asia. They were twisted, bent together and displaced, and the sediment layers were folded and penetrated by new magma rocks.

For 300 million years ago, Asia collided with Europe. This was super continent Pangea, which included Gondwana. During the collision, Asia and Europe were solidly welded together in the Uralids, whose western part is now raised like the Ural Mountains.. At the gathering of Pangea, a Precambrian massif from Gondwana, Serindia, was added to the south of the Altaids. Pangea was already permeated by fractures and rip-off zones, as it for 240-150 million. years ago in the Triassic and Jurassic were divided into several continents and plates. Asia thus became part of the Eurasian Plate. At the same time, a large cordoned-off sediment basin was developed in the western Siberian lowlands. Here, thick fresh and brackish water deposits with an unusually high organic content were deposited, as now, after just over DKK 100 million. years of storage, has matured into hydrocarbons and forms some of the world’s largest oil and gas deposits.

The youngest growth zone, the Tethysides, was developed along the southern and eastern edges of the Eurasian Plateau over the last 250 million years. Seabed dispersal in the oceans south and east of the Eurasian Plateau carried archipelagos and small and large continental fragments from the fragmented Pangea towards Asia. The ancient continent fragments came from the African part of Gondwanaland and from a now completely divided continental area, Cathysia, which lay north of Australia. In Northeast Asia, crust was added from the North American Plate.

The “alien” island arcs and continental fragments of the Tethysides were interconnected by Cimmeric and Alpine mountain ranges, folded in the Triassic-Old Cretaceous and in the Younger Cretaceous-Tertiary, respectively. The Cimmerian collisions affected the nearby parts of the Altaids, where The Tien Shan Mountains were pushed up north, so deeply buried oil shales in the Late Permian-Mesozoic Junggar Basin were raised and slightly folded, creating rich oil and gas fields in the marginal parts of the basin.

During India’s northern drift away from Madagascar, repeated volcanic eruptions occurred in early Tertiary, forming Deccan’s plateau basalts on top of dilapidated bedrock and rift zones filled with Permian-Mesozoic sediments. For 50-45 million. years ago, India’s broad northern shelf collided with Asia, and India has since been pushed further and further north into the Eurasian Plate like a rambuk. The shelf was thus penetrated by excesses and stacked up in the Himalayan mountain range south of the Indus-Tsangpo suture, where remnants of oceanic crust and a trapped arch are preserved. Mens Himalayaraised, the rivers led the decomposition material south. It now fills the depression beneath the Indo-Gangetic Plain and forms two larger deposit cones that extend far into the Arabian Sea and the Bay of Bengal. During the rise of the Himalayas, a total of 20 million is estimated. km 3 to have been removed by the erosion.

The collision and India’s sustained northward drift in the Lower Tertiary and Quaternary brought India about 4,000 km closer to Angara. The crust during the Indus-Tsangpo suture and the Tibetan Highlands became unusually thick, 65-80 km. At the same time, large parts of the previously formed growth belts north of the Indus-Tsangpo suture were tectonically revived, forming the high mountain ranges and high plateaus that now characterize the landscapes of Central Asia. India’s northwestern “corner” was pushed deep into the Cimmerian folding belt where the Pamirbjerg massif was raised. In Tibet and China, large, still seismically active lateral faults developed, and worn fold folds in the Altaids were transformed into young quarry mountains. Even at the southern edge of Angara, the Baikal rift was torn up like a deep wound that went all the way down to the bottom of the earth’s crust.

India’s pressure also drove the Eurasian Plate north; it may have initiated the development of The Japanese Archers, which have a foundation of ancient crust. North of Korea, fractures in the rim of the plate loosened a strip of the old mainland crust, and it remained while the Eurasian Plate drifted north, and the Sea of ​​Japan was opened by rapid seabed dispersal for approximately 15 million years ago. In the young depositional basins between the mainland and the volcanic island arches in East and South Asia, where the heat flow is large, significant oil and gas deposits have developed in a relatively short time.

Asia’s volatile geological history with lively and varied igneous activity has meant that the continent is extremely rich in mineral resources. Among other things, iron, nickel, platinum, chromium, tungsten, molybdenum, uranium, tin, lead, copper, gold, silver, antimony and mercury. Very famous are the Siberian diamond deposits, which are connected to deep crater pipes, where diamond-bearing mantle rocks from at least 150 km depth have been explosively carried up into the otherwise extremely stable crust of the Angara core. It happened for 450-150 million. years ago, while new growth belts were being developed around the core. Diamonds are also mined in the Ural Mountains and have most recently been found in some localities within the Altaids.

Sedimentarily formed phosphate-rich layers are widespread in Kazakhstan and eastern Siberia; they are extracted for fertilizer. Asia also houses large deposits of coal and lignite; wrestling takes place in central Siberia, China, Vietnam, India and Indonesia.