试论鄂尔多斯盆地奥陶系成钾条件及找钾方向

鄂尔多斯盆地奥陶纪含盐建造且具含钾性是目前世界已知的唯一特例 ,因此 ,对其成盐成钾条件及找钾方向的研究具有重要的意义。鄂尔多斯盆地构造及地层研究表明 ,奥陶系具有成盐成钾的有利条件 ,也具有盐层的良好保存条件。古成盐环境和古盐湖卤水生物、物化条件以及钾石盐岩分析表明 ,下奥陶统马家沟组五段六亚段和四亚段 (O1m5-6、O1m5-4 )是利于钾盐沉积的 ,即是找钾的有利层段 ;古构造和古地理研究表明了成钾的有利地区是 :西北次凹 ,南部次凹 ,西南部次凹和北部次凹。

ON CONDITIONS FOR POTASSIUM-FORMING OF EERDUOSI BASIN DURING ORDOVICIAN PERIOD AND DIRECTION OF POTASSIUM-HUNTING IN IT

The salt containing formations in the Eerduosi basin represent those exclusively potassium carrying in the world so it will be of significance to study their conditions for potassium forming and direction of potassium hunting. Structural and stratigraphical studies indicate that these formations bear environments favorable for potassium forming as well as for potassium preserving, and as shown by probes to their salt yielding environments (salt lakes) and potash minerals, they,particuarly the Nos. 5 and 4 submember(O 1 m 5-6 O 1 m 5-4 ) of the No. 5 member of the lower Ordovician Majiagou formation, is extremely compatible with potash resources and hence become targets for potassium exploring. Concretely speaking, emphases should be put on such paleostructures ans paleogeographies as the northwestern, southern, southwestern and northern sub depressions in the basin.