A spatial analysis method for geochemical anomaly separation

Qiuming Cheng

doi:10.1016/S0375-6742(96)00035-0

1996-11-01

226

PRE

Qiuming Cheng *

Agterberg, FP

BonhamCarter, GF

DOI：10.1016/S0375-6742(96)00035-0

原文链接

原文求助

摘要

En 中文

One purpose of using statistical methods in exploration geochemistry is to assist exploration geologists in separating anomalies from background. This always involves two types of negatively associated errors of misclassification: type I errors occur when samples with background levels are rejected as background; and type II errors occur when samples with anomalous values are accepted as background. A new spatial statistical approach is proposed to minimize errors of total misclassification using a moving average technique with variable window radius. This method has been applied for geochemical anomaly enhancement and recognition as demonstrated by a case study of Au and Au-associated data for 698 stream sediment samples in the Iskut River area, northwestern British Columbia. Similar results were obtained using the fractal concentration-area method on the same data. By employing spatial information in the analysis, the process of selecting anomalies becomes less subjective than in more traditional approaches.

Keyword:

spatial analysis

GIS

pattern recognition

anomaly separation

concentration-area method

stream sediment geochemical data