geological ground survey

基本解释

Consequently, a geological survey of the under-ground, rock structure must be carried out. If it is thought that the rocks in a certain area contain oil, a "drilling rig" is assembled.
因此，仅仅靠研究地层表面，无法确定有关石油，必须对地下的岩石结构进行地质勘测。
ens.ccit.edu.cn
As oil is found deep in the ground, its presence cannot be determined by a study of the surface. Consequently, a geological survey of the underground rocks structure must be carried out.
因为石油深埋在地下，靠研究地面，不能确定石油的有无，因此，对地下岩层结构必须进行地质勘探。
fl.yangtzeu.edu.cn
The geological mapping aimed at tracing the structures of the Sanshandao gold deposit was carried out in the Cangshang Covered Area in 1979, with the ground magnetic survey being the essential work.
本文介绍的是以地面磁法测量为主，于1979年在仓上覆盖区，以追索三山岛金矿构造为目的地质填图工作。

Virginia Burkett is the scientist at the U.S. Geological Survey who has analyzed the ground-based measurement of subsidence.
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