多层界面快速反演在高精度石油重力勘探中的应用

重力勘探作为一种快速普查方法，在深部地质构造研究、区域地质构造划分及找矿勘探中均已取得显著的地质效果。自８０年代后期，由于在重力测地工作中使用红外测距仪及高精度ＧＰＳ定位技术，确保了重力测点位置及高程有较高的精度；在重力观测中普遍采用目前世界上精度最高的Ｌａｃｏｓｔｅ型重力仪进行基点联测，采用对恒温系统改进后的Ｗｏｒｄｅｎ重力仪进行重力测点观测，使得重力测量的质量及精度都有了很大提高，为扩大重力法的应用提供了条件。本文给出的一例是；在我国某含油沉积盆地上，根据对实测１：２５０００高精度重力资料（布格重力异常总观测均方误差：６０×１０￣－８ｍ／ｓ￣２）的处理及约束信息下多层界面反演结果，确定有利油气聚集的圈闭范围，推断含油层的大致规模。

RAPID INVERSION OF MULTILAYER SUBINTERFACE AND APPLICATIONS TO PETROLEUM EXPLORATION OF GRAVITY WITH HIGH PRECISION

Gravity exlporation, being a quick reconnaissance survey method, has achieved obvious geological effect in research of deep geologic structure, division of regional geologic structure, and prospecting of mineral resources. Because of applications of infrared surveying and high accuracy GPS techniques in topographic surveying since late of 1980s, the gravity stations can be loeated very precisely. The Lacoste gravimeter, being the precisest gravimeter in the world at present, is used for base station surveying, while the Wor-with temperature balance system is used for gravity observation at stations, which have improved highly the quality and precision of gravity measurement and extended application scope of the gravity method. A practical example is given in this paper, that is, according to measured gravity data with the scale 1: 25000(chief root mean square error of Bouguer gravity is 60 10 m/s~2) over an oil-bearing basin in China, the hopeful region for oil accumulation has been determined and the dimensions of the reservoir has been inferred by processing the data and multilayer inversion with constraint.