【摘要】 针对在塔中地区Zh1井5 000m以下奥陶系鹰山组钻遇的一套白云岩岩溶储层厚度小(≤7m)、波阻抗差小(≤717kg/(m2.s))、非均质性强的特点,首先从地震正演模拟出发,模拟了在实钻井条件下以及当岩溶储层孔缝洞内充填物性质发生变化时的地震波场响应。结果显示这套岩溶储层在叠加剖面上绕射波比较发育,在叠后深度偏移剖面上呈现出峰-谷-峰似串珠状的反射特征,且随着充填物性质或流体含量的增多,其串珠状反射强度明显增强。据此,利用研究区的三维叠后时间偏移资料,采取有针对性的地震预测方法和技术,提取出引起岩溶储层发育的不同地质场源的地震特征信息,如反映地震波场能量大小的振幅属性,反映速度、密度变化的波阻抗信息,古裂缝分布场信息和古地貌信息等,共同对这套岩溶储层的优势发育区进行了预测。预测结果表明,岩溶储层的优势发育区主要分布在三维区域的中西部,并且在发育区内地震剖面的显示特征与地震正演模拟结果相一致,从而证实了预测结果的有效性。更多还原

【Abstract】 Aims at the features that the thickness of reservoir stratum is thin(≤7m) and the wave-drag is small(≤717kg/(m2·s) and the isotropy is poor as well in a dolomite reservoir stratum belonging to the Yingshan team of the Ordovician system met at 5 000m deep in drilling well Zh1 in Tazhong,a positive-manoeuvre simulation to the response of seismic wave field is made under the condition that the features of the fracture’s filling in the karst reservoir stratum occurring changes when drilling in reality.The simulation proves that the diffraction wave of this karst reservoir stratum is relatively developed on the stack profile and that peak-valley-peak shaped reflection occurs on the profile which gets more and more obvious with the increase of liquid fillings.Accordingly,three-dimensional post stack time data is used to collect the seismic features’ information in different wave filed of the karst reservoir stratum by means of targeted predictive measures and techniques to earthquake.The collected information includes amplitude that reflecting the energy of the wave field,wave impedance that reflecting the change in velocity and density and the paleo-fracture’s distribution and paleo-geomorphology as well,is used to predicate the dominant developing position of the karst reservoir stratum.They show that the main distribution of paleokarst reservoir is along west part in 3D area and its characteristic of seismic reflection is the same as the modeling’s.The results show clearly that the predicted methods are correct.更多还原