地震属性和瞬变电磁技术在煤田勘探中的应用

Joint application of seismic attributes and transient electromagnetic data in the coalfield exploration

煤层的富水区严重威胁煤矿的生产安全,探明富水区的分布和断层、陷落柱等含水构造的发育情况,可以有效地指导煤矿的水害防治工作。地震属性可以有效识别断层、陷落柱等地质异常体,但难以对地层富水性进行探测。断层、陷落柱的电阻率主要取决于岩层的破碎程度及富水性,富水断层、陷落柱的电阻率远小于非富水断层和周围非富水地层,这是利用瞬变电磁探测含水断层、陷落柱和富水区的地球物理依据。本文结合华南某煤矿的应用实例,证明结合地震属性与瞬变电磁数据对探测煤田富水异常区效果良好。

Water-rich anormal bodies such as faults,collapsed columns and other structures in coalmines pose a serious threat to the safety of coalmine operations.To determine this kind of anormal bodies is very helpful for mining operations.Seismic attributes can identify anormal bodies,but it’s difficult to tell the difference between water-rich anormal bodies or dry anormal bodies.So the joint use of seismic attributes and transient electromagnetic data is proposed to tell the difference.The resistivity in structures shows rock fragmentation and rock water-content.Water-rich faults and water-rich collapsed columns have much smaller resistivity than water-poor faults and water-poor collapsed columns.This geophysical observation obtained from the transient electromagnetic method can be used to detect water-rich anormal bodies in coalmines.In this paper,we demonstrate an example in a coalmine in China,in which water-rich anormal bodies are clearly detected based on the joint use of seismic attributes and transient electromagnetic data.