Research on Element Geochemical Characteristics of Coal-Ge Deposit in Shengli Coalfield, Inner Mongolia, China

Abstract

The newly found coal-germanium deposit in Shengli Coalfield in Inner Mongolia is a super-scale germanium deposit. It is the largest coal-germanium in the world with 1805 ton proven resource of germanium. In this deposit, the elemental geochemical characteristics show that the alkaline elements, such as Ca, K, Na, Mg, Al, and so on are enriched, and positively correlated to germanium; that with increasing germanium content, LREE enrichment is gradually weakened and HREE is gradually enriched; that the germanium content is negatively correlated to ∑REE and LREE, while positively to LREE/HREE and δEu, and negatively to La/Yb, La/Sm, (La/Yb) n, (La/Sm) n and δCe; that the content of germanium is negatively correlated to ash index of coal. The coal-forming swamp with sluggish water favored the sufficient absorption of germanium from solution by organic matters. The coal-germanium deposit of Shengli Coalfield is formed in the weaker alkaline and stronger reductive environment. REE geochemical characteristics in coal-germanium deposit have inheritance, and REE mainly comes from inorganic materials in the source area. And, the rocks from the southwest margin of the basin are rich in germanium, and probably become the original source of germanium of this coal-germanium deposit. The supply of germanium from the source area and the hydrologic geology conditions for germanium coming into coal forming swamps are the controlling factors for germanium enrichment.