近地表地球物理数据的联合反演成像

The near surface area in the earth (0-1 km) is often very complex, it not only affects our capability to image the deep earth, but also directly impacts human's living environments, resource exploration, and efforts for construction engineering. Geophysical prospecting has established imaging and delineation approaches for looking into the earth with multiple methods, including seismic, gravity, d.c. resistivity, and electromagnetic technologies. The research interest is moving from processing and interpreting each type of data independently toward joint inversion. Geophysical inversion is nonunique, therefore, results from multiple geophysical methods are often inconsistent even for imaging the same geological target. Each method is also limited in its own way. Only by integrating multiple geophysical data and performing joint inversion, we could possibly utilize most of the data information, constrain imaging results, and enhance resolving capabilities. This proposal is to present a joint geophysical imaging approach that combines seismic waveforms, high-precision micro-gravity measurements, d.c. resistivity measurements, and transient electromagnetic data for imaging the same geological target. The goal is to reconstruct a subsurface image delineated by seismic velocity, density, and resistivity with geologically consistent structures and following petrophysics principles as well. We shall apply the fast search approach in the web search engine for creating initial models close to the true solution.

地球近地表构造(0-1公里深)常常十分复杂,既影响从地表探测地球深部构造的准确性,又是地球构造离人类居住最近的部分,直接影响人类生活的环境安全，资源开发和工程建设。地球物理学建立了对近地表地球构造与岩石物性的定量描述与多种数据测量方法，包括地震，重力，地电等,并且目前成像方法已从分别处理不同的地球物理数据进入联合反演地球物理数据的科研阶段。地球物理反演结果是不唯一的,采用联合反演才有可能约束成像的多解性并提高解析度。目前联合反演的主要难点在于约束不稳定，参数复杂，难以建立对多种地球物理测量都较接近的初始模型，因而在实际应用中有困难。本课题将研究勘探地震全波形，高精度微重力梯度测量，直流地电测量，和瞬态电磁测量数据的联合参数反演与联合物性约束的新方法。引入岩石物理学的物性作为约束条件，并采用互联网搜索引擎的快速搜索技术查出同时初步满足多种地球物理数据特征的起始模型,推进实现联合反演的实际应用

地球近地表构造(0-1公里深)常常十分复杂, 地质年龄短，区域差异大，既影响从地表探测地球深部构造的准确性, 又是地球构造离人类居住最近的部分, 直接影响人类生活的环境安全，资源开发和工程建设。地球物理学建立了对近地表地球构造与岩石物性的定量描述与多种数据测量方法，包括地震，重力，地电等, 并且目前成像方法已从分别处理不同的地球物理数据进入联合反演地球物理数据的科研阶段。地球物理反演结果是不唯一的, 采用联合反演才有可能约束成像的多解性并提高解析度。目前联合反演的主要难点在于约束不稳定，参数复杂，难以建立对多种地球物理测量都较接近的初始模型，因而在实际应用中有困难，国内外实际数据应用实例少。本课题完成了研究勘探地震全波形与走时，高精度微重力梯度测量，直流地电测量，和瞬态电磁测量数据的联合参数反演与联合物性约束的新方法。引入岩石学的物性作为约束条件，并采用互联网搜索引擎的快速搜索技术查出同时初步满足多种地球物理数据特征的起始模型, 推进了实现联合反演的实际应用。