万安盆地构造沉降与沉积速率及其油气资源前景

Tectonic subsidence,sedimentary rates and petroleum resources potential in the Wan'an Basin

万安盆地是南海重要的新生代含油气盆地之一,是较为典型的新生代走滑拉张盆地。根据对横穿盆地的地震反射剖面的平衡剖面模拟和构造沉降速率、沉积速率的计算,认为万安盆地曾经历了3次快速的构造沉降。2.6Ma以来,沉积速率最大。万安盆地的沉降与沉积速率和盆地构造演化过程密切相关,各构造演化阶段分别控制了盆地中油气的生成、运聚和保存等成藏条件与过程。

The Wan＇an Basin as one of major Cenozoic petroleum basins in the South China Sea is a representative Cenozoic strike-slip pull-apart basin.Inferred from the calculations of balanced profile modeling,tectonic subsidence rates and sedimentary rates for the basinwide seismic reflection profiles,the Wan＇an Basin may have experienced three phases of rapid tectonic subsidence.The sedimentary rates also came up to a climax from the 2.6Ma onwards.A close correlation exists between the tectonic subsidence rates and sedimentary rates of the basin,which have exercised a major control on the generation,accumulation,migration and preservation of the hydrocarbons in the basin.