论文部分内容阅读
压力是天然气水合物资源量评价的重要参数.常规基于速度分析的压力预测方法过多依赖于经验公式,精度较低、地质意义不明确,难以满足资源量评价的需求.为了获取更可靠的含水合物沉积层压力分布及演化特征信息,本研究采用基于地质模型的流体压力模拟方法对区域压力场进行研究.基于沉积压实模型的流体压力模拟方法由于将地质信息与地震数据有机结合起来,因而不但能够获取现今压力场的状态,而且能够对压力场的演化特征进行分析.通过结合南海1148站位资料,模拟得到了研究区浅层的孔隙度、超压及流体压力数据,通过与实际数据对比,进行误差分析,获取的模拟数据与实际数据误差较小,验证了该方法的准确性和有效性.模拟结果表明,沉积速率和渗透系数对模拟结果影响较大,沉积速率增加,孔隙度增加,超压增加,有效应力减小,渗透系数增加,孔隙度降低,超压降低,有效应力增加,计算误差很可能是二者共同引起的.该方法可以为现有的水合物资源评价技术体系提供有力支撑.
Pressure is an important parameter for evaluating natural gas hydrate resources. Conventional pressure prediction methods based on velocity analysis rely too much on empirical formulas with low accuracy and uncertain geological meaning to meet the needs of resource assessment. In order to obtain more reliable water-bearing In this study, the study of regional pressure field is carried out by using the fluid pressure simulation method based on geological model.Fluid pressure simulation method based on sedimentary compaction model, due to the organic combination of geological information and seismic data, Therefore, not only the current state of pressure field can be obtained, but also the evolutionary characteristics of the pressure field can be analyzed.According to the data of 1148 stations in the South China Sea, the data of porosity, overpressure and fluid pressure in the shallow area of the study area are simulated, The results show that the deposition rate and permeability coefficient have a great influence on the simulation results, the deposition rate increases, and the porosity Degree increases, overpressure increases, effective stress decreases, permeability increases, porosity Low pressure drop over the effective stress increases, the calculation error is likely to be a common cause of both. The method can provide strong support for the prior art hydrate resources evaluation system.