ABSTRACT
In support of IGCP 259 (International Geochemical Mapping) and IGCP 360 (Global Geochemical Baselines), a pioneer project designed to test the feasibility of wide-spaced global geochemical mapping: “Environmental Geochemical Monitoring Networks and Dynamic Geochemical Maps in China” (EGMON), was launched in 1992. The aims of this project are to study the suitability and feasibility of floodplain sediment as a global sampling medium, to develop the methodologies of wide-spaced sampling of such sediment and to study the broad geochemical patterns in China in order to obtain an overall assessment of the country’s mineral resource potential and an overview of its environment.
529 floodplain sediment samples with an average density of 1 sample per 15000 km were taken all over China. Geochemical patterns revealed by wide-spaced floodplain sediment sampling show great coincidence with RGNR (Regional Geochemistry-National Reconnaissance, China’s national geochemical mapping program) and SEBV (Soil Environmental Background Values in China) broad geochemical patterns. Geochemical maps produced by data from wide-spaced floodplain sediment sampling show that there is an important Pt-Pd geochemical province in Southwestern of China. Changes in Hg and P distribution patterns in surface and deep samples are noted; Hg and P pollution is occurring over large areas in China. An area of soil vulnerability is identified in Southeastern China. A chemical time bomb of aluminum similar to the one in central Europe in Southeastern China is predicted preliminarily. Large scale forest dieback may occur within these areas in the future.
