利用比值DEXP进行重力梯度数据深度成像

Using ratio DEXP for depth imaging of gravity gradient data

针对传统DEXP快速成像结果依赖于地质体构造指数的缺点,笔者提出了利用重力异常不同阶垂向导数比值DEXP的方法。该方法使得成像结果独立于地质体构造指数。地质体的深度估计完全自动化,仅需要寻找比值DEXP成像结果的极大值点位置。通过该方法估计出的深度结果,可以进行地质体构造指数的估计。通过模型试验,证明该方法能准确地估计出地质体的深度位置以及地质体的类型。将该方法应用到Bell Geospace公司在Vinton Dome测得的Air--FTG全张量重力梯度数据中取得了很好的结果。

Traditional DEXP fast imaging method depends on the structure index of geological bodies. Aiming at the disadvantage,the authors used different order vertical derivatives of gravity data to define the ratio DEXP method. This method makes the imaging result independent from the structure index. The estimated source depths are fully automatic,and only the position of extreme point of the ratio DEXP image is needed. Through the estimated depths,we can determine the structure index of each source. Via model test,the authors proved this method can accurately estimate the depth and the types of geological bodies. Finally,the authors applied our new method to real Air-FTG gravity gradient data acquired by Bell Geospace for the Vinton Dome,and it got well results.