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What are China's four major sea areas? Donghai is just one of them!

Where are China's four major sea areas? The Bohai Sea (inland sea), the Yellow Sea (the western part of the sea is the Yellow Sea of China), the East China Sea (the Chinese region of the sea is the East China Sea) and the South China Sea (the Chinese region of the sea is the South China Sea) are connected to each other. They span the temperate zone, subtropical zone and tropical zone and are distributed in an arc from north to south. They are the marginal sea in the west of the North Pacific. It is called "China's offshore" and is the four largest sea area in China because it is close to the Chinese mainland.

The Bohai Sea, the Yellow Sea, the East China Sea and the South China Sea are collectively called China's four major sea areas, which are connected with each other. They span about 32 longitudes from east to west and 44 latitudes from north to south, with a total area of more than 4.7 million square kilometers.

1. Bohai Sea

The Bohai Sea is the northernmost inshore of China and the inland sea of the people's Republic of China. At the same time, it also belongs to the category of inland water. The Bohai Sea is composed of Liaodong Bay, Bohai Bay, Laizhou Bay and the central basin. The main rivers entering the sea are the Yellow River, Liaohe River, Luanhe River and Haihe River, with an annual total runoff of 88.8 billion cubic meters. The terrain tilts from the coast to the center and the Strait, and the terrain is monotonous and flat.

The Bohai Sea is the northernmost inshore of China and also the shallowest semi enclosed inland sea in China. It is surrounded by land on three sides, adjacent to Liao, Ji and Jin Lu, and connected with the Bohai Strait and the Yellow Sea in the East. The South and north sides of the Strait are guarded by Shandong Peninsula and Liaodong Peninsula.

The Bohai Sea is about 556 kilometers long from north to South and 236 kilometers wide from east to west, with a total area of 77000 square kilometers. It is composed of Liaodong Bay, Bohai Bay, Laizhou Bay and central basin, with an average depth of about 18 meters. The main rivers entering the sea are the Yellow River, Liaohe River, Luanhe River and Haihe River, with a total annual runoff of 88.8 billion cubic meters.

2. Yellow Sea

The Yellow Sea is a marginal sea between China and South Korea. It is a semi closed sea area in an approximate north-south direction. It is bounded by old fellow iron hill at the southern tip of the Liaodong Peninsula and the Penglai corner of the northern coast of Shandong peninsula.

In the south, it is bounded by the connecting line between Qidong mouth on the North Bank of the Yangtze River Estuary and the southwest corner of Jeju Island, and connected with the East China Sea. The average water depth of the Yellow Sea is 90m (another is 44m). The seabed is relatively flat, and most of the water depth is more than 60m. The name of the Yellow Sea comes from its yellow waters.

3. East China Sea

The East China Sea is surrounded by the Chinese mainland and Taiwan, and the Korean Peninsula, Japan's Kyushu and Ryukyu Islands. The northeast is connected to the sea of Japan through the Strait of Juma, and the southwest is connected to the South China Sea through the Taiwan Strait.

4. South China Sea

The South China Sea is located in the south of the Chinese mainland. It is one of the three largest marginal seas in the Western Pacific Ocean. It has an area of about 3 million 500 thousand square kilometers. The total area of China's territorial sea is about 2 million 100 thousand square kilometers. It is the largest and deepest water area in China's coastal waters. Its average depth is 1212 meters, and its maximum depth is 5559 meters.

The geographical profiles of the various sea areas are bounded by the connecting line between the two islands of the old fellow and the Yellow Sea, from the old island of Shandong to the Penglai corner of the miyuri archipelago. The Yellow Sea and the East China Sea are bounded by the connecting line from the north corner of the Yangtze River Estuary to the southwest corner of Jeju Island, South Korea; There are different views on the boundary between the East China Sea and the South China Sea. It is generally recognized that the boundary is the connecting line between Nan'ao Island and Taiwan Eluanbi.

The terrain tilts from the coast to the center and the Strait, and the terrain is monotonous and flat. There are ancient coastlines and remnants of ancient rivers on the seabed. Bohai Sea is a Mesozoic Cenozoic subsidence basin, and its basement is Precambrian metamorphic rock.

Quaternary sediments are 300 ~ 500m thick and mainly terrigenous materials. Silty clay ooze and clayey ooze are distributed in the three bays. There are many fine silt, coarse silt and fine sand in the middle. Gravel and shell fragments in the north of the Strait; The southern part of the Strait is fine-grained.