MIDDLE JURASSIC SPOROPOLLEN ASSEMBLAGES FROM TANGQIAN-3 WELL OF THE SANTANGHU BASIN, XINJIANG

Abundant sporopollen of about 120 species referred to 52 genera and some acritarches (2 species of 2 genera and 1 indeterminate type) were disco vered from Tangqian 3 well of the Santanghu basin, Xinjiang. They are grouped into two assemblages namely Cyathidites minor Osmundacidites Cycadopites Quadraeculina assemblage, Kraeuse lisporites manasiensis Classopollis Quadraeculina as semblage. Based on the assemblages, the author considers the first assemblage to be early Middle Jurassic in age, and the second assemblage to be late Middle Jurassic. During early Middle Jurassic the climate was warm and wet in the Santanghu basin of Xinjiang, in a temperate—subtropical zone. During late Middle Jurassic the climate was also warm, but became drier than early Middle Jurassic, in a subtropical zone.