• 责任者：Liu Chenglin (Key Laboratory of Metallogeny and Mineral Assessment ; MLR ; Institute of Mineral Resources ; Chinese Academy of Geological Sciences ; Beijing 100037 ; China)
• 刊名：Acta Geoscientica Sinica
• 出版年：2013
• 卷期：34(5)
• 关键词：钾盐矿床 ; potash deposit
• 页码：p.515-527
• 图表：6 illus., 6 tables, 50 refs.
• 分类号：1002
• issnNo：ISSN1006-3021
• isbnNo：CN11-3474/P

     Global plate movements obviously control the formation of supergene potash deposits. The formation of potash deposits underwent several distinct changes from the Paleozoic period to the Mesozoic-Cenozoic periods. That is, the potash deposits were formed mainly in the epicontinental basins in the Paleozoic stable giant cratons, in the Tethyan ocean basins in Mesozoic, and in continental rift basins in Cenozoic period. The sources of potash deposits were firstly mainly derived from sea water in the Palaeozoic period, then changed into the mixed sources comprising non-marine sources composed of deep materials brought by volcanic activities, earth＇s surface water and sea water. Non-marine deep sources were even the primary sources especially in continental rift basins. The periods of potash formation of the continental rifting basins just corresponded with the splitting of Pangeasuper-large continent and the closing of Neo-Tethys, and these evaporite basins were located in the two tectonic regions. So the potash formation of the rifting basins was probably the inevitable result of the Earth＇s crust tectonic movement. There are some typical potash deposits that occurred in rift basins, such as the Cretaceous potash deposit in Republic of Congo that occurred at the beginning of the Atlantic rifting, the Tertiary potash deposit that occurred in the Rhine graben, and the Dana Gil potash deposit that occurred in Ethiopia. Moreover, there are plenty of potassium-rich brine deposits, such as the Dead Sea, some salt lakes in East African Rift Valley, the Salton Sea in the USA, and China＇s Jiangling depression. These brine potash deposits are characterized by volcanic activities and hot springs, which are typical for the deep source supplement. Although the sizes of these rift basins are relatively small, there exist a great number of potash resources up to billions of tons in reserves of KCI. In this paper, the author give a review of the characteristics of potash deposits, sources and mineralization in the continental rift basins, and propose a potash-forming model for small-sized rift basins. Potash formation of the continental rifting might be divided into two stages, i.e., the solar-pond stage in which salt lakes under going evaporation, and the stage of underground geothermal action. Three kinds of mechanisms of the potash formation include evaporation, dissolution of the former crystallized salts, and reformation of the brine. Based on the understanding of the potash-forming model in rifts, the authors gained some successes in the exploration of potash deposits in Jiangling rift depression. It is thus held that further study of the mineralization of potash-forming in continental rift basins, some of which are well developed in China, can provide a theoretical basis and guidance for potash exploration in China＇s rift basins.