地表油气化探异常的解释与评价

油气化探中地表地球化学异常大量呈环形分布。在二连盆地桑根达来工区进行地表化探中，发现不同地球化学指标形成的地球化学异常的空间分布上表现为正环形组合和反环形组合。文中结合石油地质条件，通过数字模拟和异常形成的时间序列分析得出：正环形异常组合表示油气向地表微渗漏持续进行，下部可能存在工业聚集的油气藏；反环形异常组合表示油气向地表微渗漏正在减弱，历史上普经存在的油气藏已经消失。

EXPLANATION AND EVOLUATION ON ANOMALIES OF SURFACE GEOCHEMICAL PROSPECTING FOR OIL AND GAS

There are great number of ring shape anomalies in surface geochemical prospecting for oil and gas.Two kinds of anomaly components,normal ring shape anomaly and abnormal ring shape anomaly, of different geochemical indicators were discovered in surface geochemical exploration at Sanggendalai in Erlianhot basin.It is suggested that normal ring shape anomaly indicates that oil and gas is being micro leakage from depth to surface and there are some oil and gas trips in depth;abnormal ring shape anomaly points out micro seepage of oil and gas is weakening and oil and gas trip had been disappeared through analysis condition of petroleum geology,numerical modelling and time order of anomaly forming.