Origin of heavy metal anomalies in soils along the Shandong reach of the lower Yellow River, China

Anomalies of heavy metal elements such as As, Cd, Cr, Cu, Pb, Zn and Ni have been found along both banks of the Yellow River during multi-target regional geochemical investigations in Shandong. These anomalies have low contrasts and are discontinuous along the river. Study indicates that the contents of heavy metals in soils of the anomaly area show significant correlation with major constituents such as SiO2, Al2O3 and Fe2O3. The contents of most trace heavy metal elements content decrease with increasing SiO2 content and increase with increasing Al2O3 and Fe2O3 contents. It may be inferred according to the close relation between the major components and soil texture that the soil texture has marked controlling effect on the formation of heavy metal element anomalies.