在山区试用高精度重力测量普查金属矿

本区为黄铁矿型铜和多金属矿的山区.在四个已知矿体中,有两个大型致密矿体已经爆破,进行了露天开采.故试验工作仅限于其他两个矿体.其一为致密铜铅锌矿（以下简称甲矿）矿体作急倾的平板状.中部浅,两端倾状.其二为浸染矿床（以下简称乙矿）,由数个平行矿条组成,其中夹有富集的网脉状矿层.根据计算,体积如甲矿的致密矿体埋藏深度不超过200米,能产生0.4-2.5毫伽的重力异常.但同等尺度的浸染矿体刖仅当埋藏深度小于20米时,才能引起0.4毫伽的异常.因此要发现上述矿床,必须保证重力测量误差（包括重力仪观测误差,各项改正误差）不大于±0.1毫伽.

A PRECISION GRAVITY INVESTIGATION ON COPPER-BEARING ORE BODIES IN MOUNTAINOUS REGIONS

The gravity survey was done at a precision of about±0.1 milligal. Big copper-bearing pyrite ore bodies buried at the depths of 100-200 meters are reflected on the gravity results. Gravity anomalies arising from inhomogeneities of the surface loess bodies and dense andesitic tuff in the bed rocks have also been noticed. Special precautions have been taken in making the terrain corrections. The computational work which would be otherwise very much involved was simplified in certain respects.