异常压力对有机质的抑制作用及其石油地质意义

板桥凹陷异常压力发育,在板深35井中发现有机质的演化明显的受到了超压的抑制作用,具有和活化能、热导率、水动力等因素造成的热演化异常明显不同的特征。综合地质、地球化学分析表明,异常孔隙流体压力对有机质热演化的抑制作用是有条件的,在超压早期发育、高原始有机质丰度和高有机质热演化产物滞留的情况下超压对有机质的演化具有明显的抑制作用,超压对有机质演化的抑制作用在深层勘探方面具有重要的意义。

Overpressure Retardation of Organic Matter and Its Significance for Petroleum Geology

Overpressure developed in Banqiao Sag, Eastern China, and obvious overpressure retardation of organic matter maturation was found in Well BS35. Such an organic matter maturity anomaly is distinctly different from those caused by variation in activation energies, conductivity contrasts, and hydrologic effects. Overpressure retardation has been proven to be conditional through integrated organic geochemical and geologic research, early developed overpressure, high original TOC contents of source rocks and the retention of the pore fluids (including products of organic matter maturation reactions) in the source rocks are three important factors affecting overpressure retardation of organic matter maturation, and overpressure retardation of organic matter maturation is quite important for clearly understanding petroleum exploration during deep burial in overpressured sedimentary basins.