The Tarim Basin is a large endorheic basin occupying an area of more than 400,000 km². It is located in the Xinjiang Uyghur Autonomous Region in China's far west. Its northern boundary is the Tian Shan mountain range and its southern is the Kunlun Mountains on the northern edge of the Tibetan Plateau. The Taklamakan Desert dominates much of the basin. The area is sparsely settled by the Uyghurs, other Turkic peoples and Tajiks.
The Tarim Basin is the remains of an ancient microcontinent that amalgamated to the growing Eurasian continent during the Carboniferous to Permian. At present, deformation around the margins of the basin is resulting in the microcontinental crust to be underthrust beneath the Tien Shan to the north, and the Kunlun Shan to the south.
The Tarim Basin is believed to contain large reserves of petroleum and natural gas, with methane comprising over 70 percent of the natural gas reserve, up to 9.2 bb. A thick succession of Paleozoic, Mesozoic and Cenozoic rocks occupy the central parts of the basin, locally exceeding thicknesses of 15 km. The source rocks of oil and gas tend to be Permian mudstones. Below this level is a complex Precambrian basement believed to be the remnants of the original Tarim microplate, which accrued to the growing Eurasian continent in Carboniferous time. The snow on K2, the second highest mountain in the world, flows into glaciers which move down the valleys to melt. The melted water forms rivers which flow down the mountains and into the Tarim Basin, never reaching the sea. Surrounded by desert, some rivers feed the oases where the water is used for irrigation while others flow to salt lakes and marshes.
The Silk Road, a series of trade routes through regions of Asia, splits into two routes: the North Silk Road along the northern edge and another along the southern edge of the Taklamakan Desert in the basin. A middle route was deserted in the sixth century. The southern trackway includes the oasis towns of Yarkand, Niya, Pishan, Marin and Khotan. The key oasis towns along the northern route are Aksu, Korla, Turfan, Gaochang and Loulan. Other key towns include Kashgar in the South-West, Kuqa in the North, and Dunhuang in the East.
Formerly the Tocharian languages were spoken in the Tarim Basin. They were the easternmost of the Indo-European languages. The Chinese name "Yuezhi" (Chinese 月氏; Wade-Giles: Yüeh-Chih) denoted an ancient Central Asian people settled in modern eastern Tarim Basin, who, vanquished by the Xiongnu, later migrated southward in order to form the Kushan Empire, which was centred on Afghanistan/Pakistan, but also extended into northern India.
The powerful Kushans expanded back into the Tarim Basin in the 1st-2nd centuries AD, where they established a kingdom in Kashgar and competed for control of the area with nomads and Chinese forces. They introduced the Brahmi script, the Indian Prakrit language for administration, and Buddhism, playing a central role in the Silk Road transmission of Buddhism to Eastern Asia.
Although archaeological findings are of interest in the Tarim Basin, the prime impetus for exploration was petroleum and natural gas. Recently research developed fine-grained analysis at the ancient oasis of Niya on the Silk Road; moreover, the work led to significant findings of remains of wattle hamlets and daub structures as well as farm land, orchards, vineyards, irrigation pools and bridges. The oasis at Niya preserves the ancient landscape. Here also have been found hundreds of 3rd and 4th century wooden accounting tablets at several settlements across the oasis. These texts are in the Gāndhārī language script native today's Pakistan and Afghanistan. The texts are legal documents such as tax lists, and contracts containing detailed information pertaining to the administration of daily affairs.
Additional excavations have unearthed tombs with mummies, tools, ceramic works, painted pottery and other artistic artifacts. Such diversity was encouraged by the cultural contacts resulting from this area's position on the Silk Road. Early Buddhist sculptures and murals excavated at Miran show artistic similarities to the traditions of Central Asia and North India and stylistic aspects of paintings found there suggest that Miran had a direct connection with the West, specifically Rome and its provinces.