By : Dhani Irwanto
Source : FB Sundaland Ancient Civilisation
Sundaland is a bio-geographical region of Southeastern Asia which encompasses the Sunda Shelf, the part of the Asian continental shelf that was exposed during the Last Ice Age. The Last Glacial period – popularly known as the Ice Age – was the most recent glacial period within the current Ice Age occurring during the last years of the Pleistocene, from approximately 110,000 to 12,000 years ago. It included the Malay Peninsula on the Asian mainland, as well as the large islands of Kalimantan, Java and Sumatera, and their surrounding islands. The eastern boundary of Sundaland is the Wallace Line , identified by Alfred Russel Wallace as the eastern boundary of the range of Asia’s land mammal fauna, and thus the boundary of the Indomalaya and Australasia ecozones. The islands east of the Wallace line are known as Wallacea, and are considered part of Australasia. It is worth noting that it is now generally accepted that Southeast Asia was the entry point of modern humans from Africa.
The name “Sundaland” was first proposed by van Bemmelen in 1949, followed by Katili (1975), Hamilton (1979) and Hutchison (1989), to describe the continental core of Southeast Asia forming the southern part of the Eurasian plate. Sundaland is bordered to the west, south and east by tectonically active region characterized by intense seismicity and volcanic activity. The tectonically active zone is effectively a mountain belt in the process of formation, and contain many of the features typically thought to be associated with accretionary orogens: there is active subduction, transfer of material at plate boundaries, examples of collision with buoyant feature on oceanic plates, arcs and continents, and abundant magmatism.
The present orogenic belt is situated at the junction of three major plates: the Eurasian, Indian, Australian and Pacific-Philippine Sea plates. It surrounds Sundaland and stretches from Sumatera to The Philippines via eastern Indonesia. It changes character and width from west to east and is composed of different segments or sutures with different character.
The glaciers started to retreat and the meltwater from the ice sheets flowed into the oceans around 19,000 years ago, raising sea levels by more than 120 meters (400 feet) at the end. The sea level rose with several periods of fast spurts. The first such spurt may have started about 19,000 years ago, rising the ocean levels some 10 – 15 meters (33 – 50 feet) in less than 500 years. A more clearly-defined accelerated phase occurred between 14,600 and 13,500 years ago when the sea level increased by some 16 – 24 meters (52 – 79 feet). The rate of sea level rise slowed between 14,000 and 12,000 years ago during the Younger Dryas cold period and was succeeded by another surge 11,600 – 11,000 years ago, when sea level may have jumped by 28 meters (92 feet). A fourth interval of rapid sea level rise occurred 8,200 – 7,600 years ago. By the mid-Holocene period, 6,000 – 5,000 years ago, glacial melting had essentially ceased.
Sundaland was the biggest area to be drowned after the last Ice Age. The drowning – believed to have been caused by the retreat of the ice sheets in northern Europe, North America and several other regions – caused land loss, no exception the flat continental shelves of Sundaland. Southwestern part of South China Sea and Java Sea were created. The Sunda Strait between the islands of Sumatera and Java, and the Bali Strait between the islands of Java and Bali were open about 10,000 years ago, connecting the Java Sea to the Indian Ocean. The South China Sea and Java Sea were connected about 9,000 years ago, separating the islands of Kalimantan and Java from the Asian Mainland. The Malaka Strait between the island of Sumatera and the Malay Peninsula was open about 8,000 years ago, connecting the South China Sea to the Indian Ocean and separating the island of Sumatera from the Malay Peninsula.
The ice-melt drowned the coastal cultures and wiped out many populations as their land disappeared. Cracks in the earth’s crust as the weight of the ice shifted to the seas set off catastrophic events compounded by earthquakes, volcano eruptions, super waves and floods. As the sea rolled in, there was a mass migration from the sinking continent. They then brought their agricultural technology as well as other skills to the new lands.
Also in youtube: https://youtu.be/g9P6SBb-Hwo
C&P: 4/3/2021 @ 20 REJAB 1442H: 7.17 AM
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