遥感信息场分层解析与构造应力场定量研究

PHASE-SEPARATION ANALYSIS OF THE REMOTE SENSING INFORMATION FIELD AND QUANTITATIVE STUDY OF STRUCTURAL STRESS FIELDS

遥感图像显现的地质构造形迹是地史以来地壳运动的最终结果,包含有历次构造变形的特征信息。因此,构造复合区不同期次构造应力场的图像解析,可将宏观构造(褶皱和断裂)和与其密切相关的微观构造(遥感大节理)有机联系起来进行构造变形组合的分解,即分不同构造层次(期次)建立其变形场,然后通过构造变形场特征的综合分析研究反演各时期应力场。环形构造及相关的环状、放射状遥感大节理与地下隐伏构造隆起在空间上有一定对应关系。本文根据弹性力学理论,提出了在遥感构造信息场分层解析基础上将有关构造信息有机组合量化,建立隐伏构造隆起的自然模型,以此数据定量计算构造应力场的理论与方法,并给出了应用实例。

A remote sensing image is a stereoscopic miniature of the natural landscape. It objectively and continually records information on the surface geometric forms and physical properties (tones/colours) of tectonic features, both the overall and the individual parts, and is a high quality summary. It also records some information on concealed structures. Therefore, using remote sensing images to analyze tectonic deformation and reconstruct tectonic stress fields not only provides useful data, but also is helpful for combining fracture systems of rocks and tectonic deformation with geological formations very well, so as to draw conclusions that coincide with objective reality.The structural feature on a remote sensing image is a synthetic result of combination of the deformations produced during the geological history of an area, including characteristic information of previous tectonic deformations. Therefore, the tectonic stress fields of different stages in the complex deformation of an area can be reconstructed by the following steps: (1) geological structures formed at different stages and in different times are distinguished using remote sensing images; (2) tectonic deformation fields at different stages are determined by analyzing relationship between microstructures (joints and fractures) and the related tectonics (folds and faults); and (3) tectonic stress fields at different stages are respectively reconstructed through a study of the features of structural deformation fields in different periods. Circular structures and related linear structures in circular or radiational patterns have certain correspondence relation in space with concealed structural rises. The authors propose a new theory and method for establishing a natural model of the concealed structural rise and then calculating the structural stress field using the quantitative data of remote sensing information on circular structures and related linear structures on the basis of the phase-separation analysis of remote sensing information field and the theory of elastic mechanics. One of the applied examples is given in the paper.