关键词: 侏罗系, 成岩作用, 压实, 成岩阶段, 吐拉盆地

Abstract: With numerous observations of thin sections and casting sections of the rocks, and the application of various analytical techniques including X ray diffraction, the main diagenesis, pore evolution and the characteristics of diagenetic sequence in the Jurassic reservoir sandstone in Tula Basin, southern Altyn Tagh, Xinjiang, are carefully studied. It is concluded that the pore evolution is both controlled by depositional conditions and affected by burial diagenesis. Compaction is the major factors turning the pore texture of the sandstone worse. Cementation of the carbonate is very weak in the early diagenesis period, and this make the dissolution weak too. The strong compaction and weak cementation are of importance that form the result of the worse reservoir space. Modified by tectonics, the clastic rocks became the better reservoir of oil and gas with its high porosity and permeability in the Tula Basin.

Key words: Tula Basin, Jurassic, diagenesis, compaction, diagenetic stages