目的利用重力异常数据微弱信息挖掘技术识别线性构造的方法,并介绍其实现过程.方法采用水平梯度法和二次垂直导数等方法提取微弱信息,利用数字图象显示技术成图.结果识别出鄂尔多斯盆地线性构造多条,分析对比鄂尔多斯盆地区域地质构造资料及重力解释成果,具有较好的吻合性.为深入研究该地区线性构造补充了新的证据.结论该方法提取了区域重力异常资料中的微弱信息,弥补用等值线图示构造信息的不足,有助于线性构造的分析.水平梯度法(最大模)和二次导数处理方法与数字图象成图相结合取得良好的解释效果.
A new method of recognition of linear structures using usual gravity data is introduced, and the actualization of this technology is also accounted for, in this paper. The horizontal gradient anomalies and two derivatives methods are adopted to extract faint information as well as other methods, and digital image display technique is used to show the results. First, 3D-upward continuation of gravity and magnetic data in different height is computed. Second, the maximal horizontal gradient modulo, significance factor "n" and angle of rotation of gradient of each point in the region are calculated, according to the algorithm in this paper, and the vertical quadratic differential coefficient of the actual-measured data is reckoned in different radii. Finally, the linear structures are recognized in different depth according to these images. The structures are then defined comprehensively combining the regional geology. A comparison and analysis between the digital image of gravity anomalies from the Ordos Basin and regional geological structures replenish new evidences for deep researching of this region's structure. In this paper, the recognized linear struc tures in Ordos Basin are consistent with the existing geology datum. The gravity and magnetic data can be shown in an image by this method, describing more clearly than the routine contour map, particularly advantaged to analyze the linear structures, and the faint information can be explained from the unusual datum of region at the same time. Through the horizontal gradient method combined with the digital image technology, a good explanation effect is achieved.