基于张量不变量的航空重力梯度数据快速成像方法

A fast-imaging method for airborne gravity gradient data based on tensor invariants

航空重力梯度数据包含更多的目标体短波长信息,本文针对梯度数据的目标体空间位置及物性参数开展快速解释方法研究。首先,分析了张量不变量在场源参数反演中的优势,并提出基于不变量的归一化快速成像方法,通过成像结果的局部最大值位置快速地完成目标体空间位置参数的估计。基于理论模型分析了张量不变量的特点及成像方法在简单模型中的应用效果。其次,为了分析成像方法在复杂模型条件下的应用效果,采用含噪异常数据、临近目标体叠加异常、深浅目标体异常定量分析该方法的适用性,理论模型模拟结果表明本文方法的成像结果对目标体空间位置具有较好的反演效果。最后将本文方法应用到Humble盐丘对应的重力异常数据中,成像结果有效地反演出目标体的水平及深度方向的展布分布,验证了本文方法的实用性。

Airborne gravity gradient data contain additional short-wavelength information about the buried geological bodies.This study develops a fast interpretation method based on the gravity gradient data for the sources’spatial location and physical property parameters.This study analyzes the advantages of the source parameter inversion method based on tensor invariants.It proposes a normalized fast-imaging method based on tensor invariants to quickly estimate the spatial location parameters of sources through the local maximum value position of the imaging results.First,the tensor invariant characteristics and the imaging method’s effect in a simple model are analyzed using a theoretical model.Second,to analyze the imaging method’s application effect in complex model conditions,the method’s applicability is quantitatively analyzed using the data added with noise,superimposed anomalies of adjacent sources,and anomalies of deep and shallow geological bodies.The theoretical model’s simulation results show that the model’s imaging results in this study have satisfactory performance on the spatial position estimation of the sources.Finally,the method is applied to the gravity anomaly data corresponding to the Humble salt dome.The imaging results can effectively estimate the distribution of the salt dome’s horizontal and depths,verifying the practicability of the method.