关键词: 层序地层学, 陆相沉积, 体系域, 储集层, 油气勘探, 柴达木盆地

Abstract: Systern tract, a basic unit of I-grade sequence, is a combination of the same-terml depositional systems controlled by water level changes (lacustrine level or sea level). Petroleurm tends to being accumulated in the depositional sand bodies of different system1 tracts. The type. and distribution of lithologic pools could be predicted by characterization of system tracts and analysis of depositional systems. In southwestern Qaidam basin, the characterization of system tracts shows that there exist developed transgressive system tract (TST) and various types of reser-voirs such as sand body of deltaic front, lacustrine beach and dam as well as local turbidite of semideep Jake. Based on synthetically geologic and seismic analyses, using digital seismic processing techniques (Jason's reservoir inversion, etc.), the sand body distribation could be de-scribed, hence predicting that in southwestern Qaidam basin mainly developed the lithologic pools of SB, TU, DT and SS types.

Key words: sequence stratigraphy, nonmarine sediment, system tract, reservoir, petroleun exploration, Qaidam basin