摘要
我国西北地区具有独特的干旱荒漠戈壁残山景观,风成砂、黄土硬壳以及下伏的膏岩层与岩屑层共同构成了浅层地表土壤的基本结构。以西北某干旱地区为例,针对剥蚀程度高且元素富集不明显的干旱荒漠区,提出了分区上异点校正法。该方法是一种建立在非常规统计学基础上的数据处理方法,直接通过某种规则将各个分区的上异点调整到统一水平上,使得每个地质单元中的异常点均能被突显出来,然后合并各个分区的数据并运用分形来确定统一的异常下限。所圈定的异常较归一化法结果能更好地与地质情况和矿化点相吻合,对低背景区弱小异常的识别以及高背景区异常的分解效果也较好。
The arid Gobi is a particular geomorphologic landscape of the northwes tern China.The surface soil in this region is composed of wind dust,loess shell, plaster layer and rock chips.Taking an arid area from northwestern China as an e xample,this paper discusses the method of unit-wise adjustment of outlier geoche mical data and its application effects.This method based on non-conventional sta tistics makes the outliers of different unit-wise on the same level through some rules,and resultantly all geochemical anomalies delineated by fractal method us ing the corrected data can be identified efficiently.The anomalies,delineated b y the method of unit-wise adjustment of outliers and fractal method,are well con sistent with the known geological setting and mineralization.Furthermore,the ide ntification of the weak anomalies and decomposition of anomalies in high backgro und area using this method,is better than the results of simple normalization.
出处
《地质科技情报》
CAS
CSCD
北大核心
2011年第1期34-41,共8页
Geological Science and Technology Information
基金
内蒙古自治区国土资源厅项目"内蒙古额济纳旗基东等四幅1:5万区域矿产地质调查"(NMKD2008-32)
关键词
分区上异点校正法
分形
异常下限
干旱荒漠区
西北地区
the method of unit-wise adjustment of outliers
fractal
threshold
gobi desert landscape
northwestern China
