瞬变电磁测深在海南福山凹陷的试验研究

Experiment with transient electromagnetic sounding in Fushan depression in Hainan Province

张小路，王钟．瞬变电磁测深在海南福山凹陷的试验研究．石油地球物理勘探，1997，32（6）：878～883采用单脉冲大功率轻便型瞬变电磁仪，在海南福山凹陷部分地区开展瞬变电磁测深试验取得了初步成果：①摸索到适合于该区的数据采集方法，即采用重叠回线装置、回线边长为400m、发射脉冲电流为100A、供电时间为40ms、采样时间长度为160ms；②采用上述采集方法，探测深度可以达到2000m；③反演的界面起伏形态可与已知井的测深资料相对比，平均深度误差为10％，最小的深度误差仅有2％。若采用回线边长600m、发射脉冲电流200A、采样时间640ms，探测深度可以达到3500m。由此可见，瞬变电磁测深方法在我国南方一些地震勘探效果不佳的火山岩覆盖区及石灰岩地区的石油勘探中，有良好的应用前景。

Experiment with transient electromagnetic sounding was conducted by using single-pulse powerful portable transient electromagnetic sounder in Fushan depres-sion in Hainan Province. The experiment has brought the following preliminary re-sults: reasonable data acquisition method, which uses the overlapped loop system, 400m of the single side length, 100A of transmitted pulse current, 40ms of power supply time, and 160ms of sampling length. The maximum probing depth is 2000m when the method is used reasonably. The undulation shape of inversion interface can be correlated to that of sounding data at known borehole, the average depth error being 10%, and the min-imum depth error being 2% only. The maximum probing depth may be 3500m when single side length of the loop is 600m, transmitted pulse current 200A, and sampling length 640ms. We can see from the experiment that transient electromagnetic sounding method has good application in oil exploration of volcanic rock and carbonate rock areas in South China where seismic exploration effect is poor.