针对复杂的石油领域四维地震勘探问题，基于流体饱和孔隙介质弹性波方程，开展快速的反演算法研究，研究利用可测量数据反演储层参数等重要物理量、识别流体边界、以及评估效用等问题。引入先进的数学理论和方法，通过数学、地球物理、石油勘探等学科的交叉融合，形成较完整的适用于复杂介质四维地震勘探的弹性波方程局域化反演模型与反演算法。本着交叉学科驱动，开发共性高效的反问题新算法，重点研究基于逆散射理论的有限元—对比源方法，并研究算法的效率改进、以及流体边界的精确识别等问题。所提出的反演的新理论和新算法，可有效解决实际石油勘探中的难题，是对地球物理反演理论的重大突破；同时，方法亦适合于其它具有复杂背景场的异常体检测问题，具有广泛的适用性。

Based on the elastic wave equation in fluid-saturated porous media, the goal of this project is to establish some effective and efficient inversion algorithms for 4D seismic monitoring problems arose from complicated oil geophysical prospecting. We will investigate the reconstruction of some important physical quantities (e.g. the reservoir parameters), identification of the fluid boundary and the utility of performance appraisals, etc. Using advanced mathematical theories and methods, as well as a discipline-crossing with mathematics, geophysics and petroleum exploration, we plan to propose some comprehensive localized inversion models and the inversion algorithms for elastic wave equation in complex 4D seismic monitoring problems. Motivated by discipline-crossing and the finite-element contrast-source inversion (FE-CSI) method which is based on inverse scattering theory, we aim to develop more novel and powerful inversion schemes. We focus on the issues of further improvements of the efficiency of the FE-CSI method and the precise identification of the fluid boundary in terms of the method. The new theories and algorithms to be formulated, in our view, will be applicable to challenging problems in real-world oil prospecting, so the results should represent a significant breakthrough for geophysical inversion theory. In addition, the algorithms to be presented will also applicable to abnormal detection problems with complicated background medium, therefore they will have a wide practical applicability.