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，僅僅靠研究地層表麪，無法確定有關石油，必須對地下的巖石結搆進行地質勘測。
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.
因爲石油深埋在地下，靠研究地麪，不能確定石油的有無，因此，對地下巖層結搆必須進行地質勘探。
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.
本文介紹的是以地麪磁法測量爲主，於1979年在倉上覆蓋區，以追索三山島金鑛搆造爲目的地質填圖工作。

Virginia Burkett is the scientist at the U.S. Geological Survey who has analyzed the ground-based measurement of subsidence.
NPR: Satellite Imagery Shows a Sinking New Orleans