Abstract:

The advantages of huge carbonate reservoirs in Riphean period （1 650～800Ma） and Wendian period （670～ 590 Ma） of East Siberian platform include the following aspects: the formation of high quality source rock of dark shale during the Riphean Aulacogen evolution stage, the long-term developed paleo-uplifts within the craton basins are the major oil and gas enrichment zones, the stable distributed cap rock of gypsum is the key for the preservation of ancient reservoirs and the lithologic reservoir with structural background is the main reservoir type for petroleum accumulation. Comparing with the Sichuan, Tarim and Ordos basins in China, the common features of carbonate reservoir in these basins include strong heterogeneity and rapid lateral alternation. The differences include the significant changing of hydrocarbon generation indicators of shale source rock, the large thickness of Mesozoic to Cenozoic sedimentation and the deep burial of the lower combination within the superimposed basins. The carbonate exploration in China should comprehensively focus on the following aspects: evaluate the shale source rock of Sinian and Cambrian, evaluate the cap-rock condition of multi-phase reconstruction superimposed basin and enhance the exploration of lithology reservoir with structural background. The recent exploration should focus on great basins, seek the great structural background and develop the great combination zones of structure and lithology. Focusing on Sichuan, Tarim and Ordos basins, we should carry out structural reservoirs exploration of large-scale uplifts and buried hills and stratigraphy and lithologic reservoirs exploration of regional unconformity, slope zones of paleo-uplifts, great pinch-out zones of strata, reef on platform margin and grain banks symbiosis with evaporate rock within platform.

Key words: clay minerals, authigenic chlorite, X-ray diffraction, physical properties, Chang 6 oil reservoir set, Ordos Basin