关键词: 柴北缘, 油气藏, 烃源岩, 圈闭, 断裂, 成藏机理, 勘探方向

Abstract:

The thoughts was based on the dissection of the typical reservoir in the west segment of the northern fringe of Qaidam basin. The formation of the reservoir in this area lies on the organic configuration in hydrocarbon birth, trap growth, reservoir-caprocks assemblage, oil remotion and accumulation and each main factors on the space on time. The distribution of oil is controlled by hydrocarbon depression strictly. The palaeo-trap and palaeo-uplift are the long-term low potential energy area that oil moves and fells on. It can catch the oil preferentially and has the advantage conditions of the growth of deep-seated primary reservoir. The formation of the low-seated secondary reservoir is inseparable with fault activity. The closing of the faults and the preservation of the traps are the decisive factors of the secondary reservoir growth. The reservoir-caprocks assemblages of Jurassic self-generating and self-reservoiring and tertiary lower-generating and upper-reservoiring grow diffusely. The favorable reservoiring capability and reservoir-caprocks assemblages are the important guarantee of the oil enrichment in great force. The organic configuration of static and dynamic factors of oil accumulation is linchpin. It controls whether the oil can be accumulated at last in this area. The synthetical opinion thinks that the palaeo-uplift which formatted at Yanshan terminal era and the tertiary palaeo-structure are the best practical and advantage next direction of exploration in the west segment of the northern fringe of Qaidam basin. At the same time, it is well worth exploring new stratum and realm too. For example, stratum unconformity of Mesozoic and Cenozoic, stratigraphic overlapped and basement buried hills etc.

Key words: Northern fringe of Qaidam basin, Reservoir, Source rock, Trap, Fault, Pool-formaing mechanism, Direction of exploration.