The Yangtze River/Yangtze River belongs to the Pacific water system and is the largest river in China. The main stream of the Yangtze River runs through central China from west to east, and hundreds of tributaries converge from north to south. The total length is 6,363 kilometers (according to the data of the State Council), including 6,397 kilometers (according to the data of Anhui Provincial People's Government), 6,403 kilometers (according to the data of the website of Sanjiangyuan National Park) and 6,380 kilometers (according to the data of the Yangtze River story). Generally, it is more suitable to use more than 6300 kilometers.
Above Yichang, the main stream of the Yangtze River, is upstream, with a length of 4,504 kilometers and a drainage area of 6,543.8+0,000 square kilometers, of which the branch from Zhimen to Yibin is called Jinsha River, with a length of 3,464 kilometers. Yibin-Yichang section, commonly known as Chuanjiang, is 1040 km long. Yichang to Hukou is the middle reaches, with a total length of 955 kilometers and a drainage area of 680,000 square kilometers. Hukou to the sea mouth is downstream, 938 kilometers long, with a drainage area of 6,543,800 square kilometers. ?
Until the Triassic period 200 million years ago, the western part of the Yangtze River basin was still occupied by the ancient Mediterranean Sea (also known as the Tethys Sea). Tibet, southern Qinghai, western Sichuan, western Yunnan, central Yunnan and western Guizhou are all vast seas, while Sichuan Basin and western Hubei are huge bays protruding eastward from the ancient Mediterranean. This bay extends all the way to the middle of the Three Gorges of the Yangtze River today.
The ancient Mediterranean, between Eurasia in the north and Gondwana in the south, extends westward from the Qinghai-Tibet Plateau to West Asia and South Europe, and southward to Indochina Peninsula, stretching for thousands of kilometers. At that time, the southern half of the middle and lower reaches of the Yangtze River was also submerged at the bottom of the sea, and the northern, northern and northwestern parts of the middle and lower reaches belonged to the eastern part of Eurasia, with high terrain.
At the end of Triassic,10.8 billion years ago, Indosinian orogeny occurred on the earth, including Kunlun Mountain, Kekexili Mountain, bayan har Mountain and Hengduan Mountain.