1:5万地质测量中的物探工作

我国即将开展大面积1:5万的地质测量,物探工作如何配合以取得尽可能多的地质信息,以提高工作质量和效益,是一个急需要研究的课题。系统开展1:5万(1:2.5万)地质测量并同时开展物探工作的国家,主要是苏联。到1982年底为止,1:5万的地质测量已覆盖苏联国土近30%。

GEOPHYSICS APPLIED TO 1:50,000 SCALEGEOLOGICAL SURVEY

Aprogram of geological survey at a scale of 1:50,000 is to be carried out in vast areas of our country. Aproblem that should be investigated is how to apply geophysical methods to a survey of such kind to obtain the maximum amount of geological information and to improve the quality of geological maps. It should be noted that in the geological survey at a scale of 1:50,000, geophysical methods must be selected according to the local structural and geomorphological features and other conditions. The present paper intends to deal with field techniques with special reference to two kinds of regions with different structural features:one in which the fold structures are either exposed or buried at a shallow depth; the second referring to regions with the fold structures buried at a great depth and with the near-surface formation comparatively gentle. Geological tasks for different stages as well as examples are also introduced. Generally speaking, the geophysical investigations in these two kinds of regions can be divided into two stages, preceding and accompanying-In the last part of the paper, geophysical techniques applicable to geological survey at a scale of 1:50,000 in areas covered by volcanic rocks, are given.