1. Introduction
Geochemical exploration has played an important role in mineral
discoveries, particularly due to China's National Geochemical Mapping
Program — Regional Geochemistry-National Reconnaissance (RGNR).
The program is almost covering all the outcropping mountainous
and hilly areas (approximately 6 million km2) mainly using stream
sediment sampling (Xie et al., 1997). However, the diverse regolith covered
terrains provide an additional geochemical challenge for mineral
exploration in China.