关键词: 潜江凹陷, 生油洼陷, 油气运移, 岩性圈闭, 含油气性

Abstract:

Banghu Syncline is the main source sag in Qianjiang Depression. The source rocks of Eq₃ and Eq₄ around Banghu Syncline has matured and generated oil and gas. Many updip pinch-out traps of lithologic sandstone are developed on the southern and eastern slopes around Banghu Syncline. The permeable sandstones accepted hydrocarbon in a way of surface supply, and oil and gas migration was driven by buoyancy. Hydrocarbon migration and accumulation in these slopes were mainly controlled by three factors. The tectonic framework controlled the migration trends of oil and gas.The hydrocarbon migration paths were controlled by special disposition of permeable sandstone conductor and migration trends.Each lithologic trap corresponding to the convergence area was limited by oil and gas migration path network.The petroliferous property of lithologic trap was controlled by volume of source rocks and hydrocarbon-generating and hydrocarbon-expulsing performances of corresponding source rock. The convergence area was in positive proportion with the petroliferous property of lithologic trap in the same combination of petroleum migration and accumulation. On the basis of prediction technology for hydrocarbon migration path in source sag, the petroliferous property of lithologic trap could be correctively evaluated.

Key words: Qianjiang Depression, source sag, oil-gas migration, lithologic trap, petroliferous property