局部空间自相关及其在勘探地球化学中的空间聚集研究

摘要

运用局部空间自相关 Moran的 Ii 和G*i 指数，研究8130 km2区域内采集的1∶20万水系沉积物1482个组合样点的空间聚集情况，与基于稳健统计学的地球化学异常下限确定方法所圈定的异常范围对空间聚集范围进行对比。结果表明，局部Ii 指数能够很好地探测出程度较弱和范围较小的空间聚集，局部G*i 指数适合于程度较强和范围大的高高聚集探测，所探测出的空间聚集范围较大。使用该方法所发现的地球化学空间聚集范围和程度符合客观实际，与已知矿床（点）吻合很好。%Using local Moran's and indexes, the authors studied spatial cluster of 1482 stream sediment samples in a specific area of 8130 km2 on the scale of 1:200000. The comparison of the anomaly range computed by robust statistics with that computed by local spa-tial autocorrelation shows that local Moran's index can well detect relatively weak spatial cluster and small areas while local index is suitable for spatial cluster detection in a strong degree of spatial cluster and large areas. The degree and area of geochemical spatial cluster by using these approaches accord with the objective reality and are in good conformity with known deposits (ore spots).