![]() Marine pollution caused by ocean dumping, waste disposal, and oil spills deep sea mining oil pollution in Arabian Sea, Persian Gulf, and Red Sea coral reefs threatened due climate change, direct human pressures, and inadequate governance, awareness, and political will loss of biodiversity endangered marine species include the dugong, seals, turtles, and whales Occasional icebergs pose navigational hazard in southern reaches Oil and gas fields, fish, shrimp, sand and gravel aggregates, placer deposits, polymetallic nodules Surface dominated by a major gyre (broad, circular system of currents) in the southern Indian Ocean and a unique reversal of surface currents in the northern Indian Ocean ocean floor is dominated by the Mid-Indian Ocean Ridge and subdivided by the Southeast Indian Ocean Ridge, Southwest Indian Ocean Ridge, and Ninetyeast Ridge major surface currents: the counterclockwise Indian Ocean Gyre comprised of the southward flowing warm Agulhas and East Madagascar Currents in the west, the eastward flowing South Indian Current in the south, the northward flowing cold West Australian Current in the east, and the westward flowing South Equatorial Current in the north a distinctive annual reversal of surface currents occurs in the northern Indian Ocean low atmospheric pressure over southwest Asia from hot, rising, summer air results in the southwest monsoon and southwest-to-northeast winds and clockwise currents, while high pressure over northern Asia from cold, falling, winter air results in the northeast monsoon and northeast-to-southwest winds and counterclockwise currents Northeast monsoon (December to April), southwest monsoon (June to October) tropical cyclones occur during May/June and October/November in the northern Indian Ocean and January/February in the southern Indian Ocean Note: includes Andaman Sea, Arabian Sea, Bay of Bengal, Flores Sea, Great Australian Bight, Gulf of Aden, Gulf of Oman, Java Sea, Mozambique Channel, Persian Gulf, Red Sea, Savu Sea, Strait of Malacca, Timor Sea, and other tributary water bodies They also help us find new natural resources and fundamentally understand the dynamics of our planet.Body of water between Africa, the Southern Ocean, Asia, and Australia These models aid in understanding how Earth’s geography and climate has evolved over geological timescales, helping us to understand the planet’s habitability and predict future scenarios. Why is this sort of information important? Because it helps build tectonic models of continental motions and formation of the continental shelves and deep ocean basins through time. Distinct curved lines to the left of the Zenith Plateau - labelled “Fracture zone bends” in the image above - record a dramatic change in the direction of India as it and Australia moved further apart 100 to 90 million years ago. Nearby, there are other clues revealing the path that India took as it and Australia separated. The Zenith Plateau still remains unsampled. The samples we recovered were continental type rocks (erupted and oceanic rocks differ significantly in composition) which indicated that this piece had indeed rifted from India. Image courtesy of L’Oréal Australia For Women in Science Fellowships. The seafloor that formed during this separation records details of the process, including many plateaus and linear features.Ĭontinental rocks dredged from Batavia Knoll in 2011. The eastern Indian Ocean formed as India and Australia separated around 100 million years ago, as part of the breakup of the southern supercontinent Gondwana. When continents break apart, the story of their separation is recorded in the ocean floor that forms between them. Ocean basins are created by motions of the tectonic plates over 10s and 100s of millions of years. What the maps show about the planetĭetailed maps of the seafloor are a powerful tool for scientists to investigate how and why the tapestry of underwater features are formed. The closer the equipment is to the seafloor, the better it is able to resolve smaller features and more subtle detail. To obtain even higher resolution data, scanning equipment can be towed at depth behind a ship or mounted on autonomous underwater vehicles (AUVs). Australia’s (now retired) Marine National Facility Vessel, the RV Southern Surveyor.
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