解析延拓法在山阳磁法数据解释中的应用

Application of Analytical Continuation Method on Magnetometric Data Interpretation in Shanyang Area

依据磁法数据处理中的解析延拓原理,对陕西省商洛市山阳县小河口镇工区的磁法勘探数据分别进行了上、下延拓:0.5、2、8、10 m及200、240、260、280、360 m的向上延拓,2、4、6、8 m的向下延拓。纵观磁异常等值线平面图可以发现,该区存在2处主要高值剩余磁异常区域,异常值分别介于80~170 n T与70~90 n T,规模分别为100 m*350 m(异常4)和230 m*250 m(异常3)。结合该范围地质填图成果,分析认为异常4是由位于约250m深处的矽卡岩脉引起的,而浅部干扰导致了异常3。该区解释延拓的应用表明向上延拓达到压制浅部干扰、突出深部异常,向下延拓压制深部干扰、相对突出浅部异常的目的。

Based on the analytical continuation principles in magnetometric data processing, have carried out upward（0.5, 2, 8, 10, and200 m, 240, 260, 280, 360 m levels） and downward（2, 4, 6, 8m levels） analytical continuations respectively for magnetic prospecting data from the Xiaohekou work area, Shanyang County, Shangluo City, Shaanxi Province. The comprehensive surveying of magnetic anomaly isogram plan can find that in the area have 2 main high residual magnetic anomalies with outliers between 80～170n T and 70～90n T and sizes 100m＊350m（anomaly 4） and 230m＊250m（anomaly 3） respectively. Combined with geological mapping in the area considered that the anomaly 4 is caused by skarn dike at depth about 250 m, while the anomaly 3 by shallow interference. The application of analytical continuation on the interpretation in the area has shown that the upward continuation can achieve the aim to suppress shallow interference and highlight deep anomalies; while the downward continuation suppress deep interference and highlight shallow anomalies.