Distribution of Cambrian salt-bearing basins in China and its significance for halite and potash finding

Abstract

Wide distribution of Cambrian salt-bearing basins is a prominent feature of older strata in Asia. The Cambrian salt-bearing sequences are mainly distributed in East Siberia of Russia, Iran, Oman, India, Pakistan, and China. The Cambrian was one of the most important epochs of potash deposition in the world. Potash salts are found in East Siberia, Iran, India, and Pakistan, and, among them, one of the largest potash deposits in the world—the Siberian Nepa Potash Basin-formed in the Early Cambrian. The Cambrian was also one of the most important epochs of rock gypsum and salt deposition in China. Gypsum deposits occur in all the three major continental blocks of China (Yangtze Block, North China Block, and Tarim Block), forming four large marine salt-bearing basins. Extensive, thick rock salt deposits have been found in the Yangtze Block and Tarim Block, where better potash-bearing hydrochemical manifestations and leaching coefficient anomalies have been found for the first time. In the North China Block, a number of gypsum deposits and occurrences have been observed and Cambrian high-salinity brine and halite crystals found in oil wells. This study for the first time relatively completely analyzes the distribution and tempo-spatial evolution of Cambrian gypsum and salt-bearing basins in China, which provide an important basis for the study of the history of Cambrian paleogeographic evolution over the globe and salt and potash exploration in Cambrian salt-bearing basins of China.