Potash assessment models and resource potential analysis in China

Aimed at calculating ore resources and providing proposal of scientific industrial policy, the authors carried out scientific researches on mineralization characteristics and assessment of resource potential in the past several years. The discovered potash deposits, which can be divided into 12 Ⅲ grade metallogenic belts, are mainly of Quaternary saline lake-type located in Cenozoic continental basin in western China with a Quaternary metallogenic age. On the basis of researches on typical deposits, regional metallogenic and predictive factors, four different kinds of potash metallogenic prediction models were summarized, namely Quarternary salt lake type, deep-subterranean bittern type, clastic rock type and carbonate type. Adopting comprehensive geological information model, the authors delineated 320 minimum predicting areas and 42 grade Ⅲ prediction areas. Furthermore, 3.263 billion tons of KCl at the depth shallower than 6000m and 1.51 billion tons of KCl at the depth shallower than 500m were predicted on the basis of metallogenic prediction model proposed by the authors. These researches indicate that the north Qaidam Basin and Tarim Basin carry more potash resources quantity than other places in China and the potash resources in the two basins are mainly of Quaternary salt-lake type and deep-subterranean bittern type. These resource potential predictions reveal the degree of the present study of potash deposits and are of great significance for potash prospecting.