不同方法在栾川北部化探数据处理中的应用

APPLICATION OF DIFFERENT DATA PROCESSING METHOD IN GEOCHEMICAL EXPLORATION IN THE NORTH LUANCHUAN

不同的地质单元具有不同的地球化学背景,在分布有多个地质单元的地区开展化探工作时,如果不考虑地质单元的地球化学背景差异,而在全区采用统一的异常下限,势必会掩盖低背景区异常或造成全区大面积异常分布。针对这一问题,有多种相应的数据处理方法。在栾川北部地区1∶5万水系沉积物测量数据处理中,分别采用了子区中位数衬值滤波法、衬度异常法、归一化法,对比认为:子区中位数衬值滤波法具有较好地削弱不同地质单元背景差异、识别弱小异常的作用,不足之处是计算和成图繁琐;衬度异常法和归一化法的计算模型近于一致,对弱小异常也有一定的识别作用。

As different geological units have different geochemical background, working in a multi -geological units district, the differentia of geochemical background in geological units must be taken into account. Otherwise, using the same threshold in the units which have low geochemical background, anomalies maybe weaken or there will be lots of anomalies in the district, There existed many methods to solve this problem. To processing the data of 1：50000 stream sediment survey in the north Luanchuan county, subregion median contrast filltering method （ SMCF）, contrast anomaly method and normalization method were used. Comparing these methods, SMCF method can weaken the difference of different geological units and identify puniness anomalies better, but processing and mapping of this method is complex. Contrast anomaly method and normalization method have the near same calculating model, and can also identify puniness anomalies.