基于界面反演增强的位场边缘识别方法

An edge recognition technique enhanced with interface inversion for potential field data

准确识别含油气构造及控矿断裂与岩体等地质边界是能源和资源勘查的重要任务之一,重、磁位场边缘识别方法在研究地质边界方面有独特的优势,已成为能源和资源勘查中不可或缺的重要手段。为增强位场边缘识别方法对深部小规模构造的识别能力,本文将界面反演与归一化总水平导数垂向导数(NVDR_THDR)位场边缘识别技术结合起来,首先利用密度界面反演技术处理重力异常,使结果能突出小规模地质构造特征,之后将NVDR_THDR作为边界提取和增强的技术处理反演的界面深度。裂陷盆地模型试验及孤立形体组合模型试验结果表明,本文方法具有明显的边缘增强效果,并且能在一定程度上平衡深部和浅部异常。最后将该方法用于鄂尔多斯盆地北部重力资料处理之中,结果也表明了本文方法可以更好地识别盆地基底小规模断裂,实际应用效果较好。

One of the pivotal tasks in energy and resources exploration is identifying geological boundaries such as petroliferous structure,ore-controlling faults,and rock mass boundaries.The edge recognition of gravity and magnetic potential data has unique advantages in the detection of geological boundaries,and has become an indispensable and important means in energy and resources exploration.We have combined interface inversion and normalized vertical derivative of the total horizontal derivative(NVDR_THDR)for potential field data to improve the effect of the potential field edge recognition method for deep small-scale geological bodies.Firstly,we invert the gravity anomaly using density interface inversion method to make the anomaly more prominent of the small-scale geological structures,then the NVDR_THDR technique is used as an edge extraction and enhancement method to deal with the density interface inversion result.The results conducted with rifted basin model and the isolated bodies model show that the proposed method has obvious advantages of edge enhancement and can balance the deep and shallow anomalies to some extent.The real gravity data test of the northern Ordos Basin also show that our method can detect the small-scale faults in the basement of the basin,which indicates that this method can be successfully used in real data processing.