Studies on the Application of Geotomography to Effective Use of Underground Space

本文研究的目的是将层析成像技术应用于地下空间的有效利用。由于弹性波的折射和绕射现象以及源和接收器布置的空间限制，导致了层析成像中的具体问题。针对这些问题进行了研究，并对分析误差进行了评定。对于弹性波层析成像中的速度层析成像，在这两年中进行了以下考虑。建立了非线性分析系统。对浸润层的分辨极限进行了讨论。通过旋转坐标系提高了测量精度。利用Akaike‘s信息准则对重建结果进行评价。开发了针对某一对源接收器的多射线路径分析技术。此外，还开发了基于初至波幅的衰减层析成像分析系统，并将其应用于野外数据。适合于有效观测预期目标响应的电阻率层析成像的固体阵列检测。开发在重建阶段生成初始值的合理技术。

The purpose of the present study is the application of geotomography to the effective utilization of underground space.The specific problems in geotomography are derived from the refraction and diffraction phenomena of elastic waves and the spatial restriction of the arrangement of source and receiver. The studies for resolving these problems and the evaluation of the analytical errors were carried out. As for the velocity tomography in the elastic wave tomography, the following considerations were performed during the two years.1. Establishment of the non-linear analysis system.2. Discussion on the resolving limitation for the dipping layer.3. Improvement in the accuracy by the rotation of coordinate system.4. Evaluation of the reconstruction result using the Akaike's Information Criteria.5. Development of the analysis technique by use of multiple ray path for a certain pair of source receiver.6. Data acquisition in the field and application of the analysis system to the field data.In addition, the analysis system for the attenuation tomography using the amplitudes of first arrival waves were developed and applied to the field data.As for the resistivity tomography, the following considerations were carried out.1. Examination of solid array suitable for the resistivity tomography which observes effectively the response from prospective target.2. Development of the reasonable technique for generating the initial values in the reconstruction stage.