盆地三维古水动力数值模拟方法及其应用

Study and application of 3D paleo hydrodynamic numerical simulation method

盆地古地下水动力是油气成藏过程的重要动力,但尚未检索到盆地三维古水动力场演化动态数值模拟方法研究的文献。从盆地演化地质模型出发,综合考虑盆地古地形、沉积压实水、地表渗入水、地层渗流性质和盆地构造演化特征等因素,建立了三维古水动力演化数值模拟模型,能够反映非均质各向异性条件下地下水的流动规律。应用该模型可以定量模拟各地质阶段盆地各地层的三维流势场、流速场、流向场,还可计算地层水交替次数,从而再现各构造运动时期的地下水活动史。用该方法对塔里木盆地现有的实际资料进行了实算模拟,获得了丰富的计算成果和大量成果图件,表明该方法具有使用和推广价值。图3彩图3参6(王孝陵摘)

The paleo hydrodynamic evolution in a basin is very important to the processes of petroleum accumulation in the basin, but so far the literature about the study of 3D paleo hydrodynamic numerical simulation method has not been found out. Beginning with geologic model description of hydrodynamic evolution, and considering synthetically paleo landform, the flow of compact driven water and that from basin surface, the character of strata in fluent and the character of the basin structural evolution, the authors created a 3D numerical simulator of paleo hydrodynamic evolution which could reflect the flow rule of unstable groundwater in the anisotropic medium. This simulator can be used to simulate the basin hydrodynamic processes in each geological period and stratum, and then acquire some parameters including 3D flow potential field, flow speed field, flow direction field and alternating times of stratum water, and finally model the active circumstance of groundwater in each geological period. This simulator has been applied to Tarim basin, the results have shown the primary evolution characters of petroleum accumulation in Tarim basin. This indicates that the method and software system is innovative and useful in basin modeling.