0　方法简介地表地球化学勘探主要是通过对地表样品的含量分析,查明各项地化指标的平面分布规律和迭合情况,再根据区域背景和指标异常下限,确定出指标数值异常区。因为化探指标异常本身包含着地下含油气情况的信息,所以结合地质资料进行综合解释,就可以为油气勘探和评价提供依? 0 Method Introduction Surface geochemical exploration is mainly through the analysis of the content of the surface samples to find out the plane distribution law and the stacking situation of each geochemical index. According to the regional background and the anomalous lower limit of the index, the numerical anomalies of the index are determined. Because geochemical anomalies themselves contain information about the conditions of subsurface hydrocarbon-bearing gas, the comprehensive interpretation of geologic data can provide a basis for oil and gas exploration and evaluation.