开封凹陷区地热资源大地电磁测深研究

A MAGNETOTELLURIC STUDY OF GEOTHERNAL RESOURCES IN KAIFENG DEPRESSION,HENAN PROVINCE

根据同类岩石中的电性异常现象可以推测热储的分布状况。开封凹陷区境内深层地下水资源较为丰富,在该区域的大地电磁测深研究表明,测区内郑汴断裂以北的大部分测点基底电阻率值很低,推测与赋存于岩层中的地热水关系密切。根据测区电性异常的分布,圈定了测区基底地热水的相对富集范围,为进一步开展地热勘查工作提供了重要依据。

Kaifeng depression,located in the southeast corner of the Jiyuan-Kaifeng depression,is enriched with deep-seated groundwater sources.The rich geothermal water rock（thermal reservoir） commonly has lower resistivity than the in-situ rock,and the reduction degree of its resistivity is related to the extent of water content,water temperature and mineralization.Based on geo-electrical anomaly,the authors inferred the distribution of the thermal reservoirs.A study of the magnetotelluric sounding method（MT） shows that the resistivity values of the basement are lowest in most surveying points north of F1 fault,implying the existence of the relationship with the geothermal water in the strata.According to the distribution of geo-electrical anomalies in the survey area,the authors locate the relatively enriched area of geothermal water in the basement of this area,thus providing an important basis for further geothermal exploration.