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阿根廷中西部内乌肯外安第斯山地区的天青山-重晶石矿床形成于早白垩世。矿床位于亚安第斯中生代地层分布区,并具有明显的与蒸发岩相有关的层控特征。沉积序列的地质演化研究,揭示出蒸发岩相的时间和空间位置。天青石-重晶石矿床主要是受地层控制的,而矿床的区域分布取决于区域构造。根据矿床的特征和成因,认为它们属于三种类型:(1)与蒸发岩相同生的天青石层状矿床;(2)由于钟乳石的生长和溶洞填充,经天青石原地“活化”作用形成的次生层控矿床;(3)再“活化”后,经富含钡的水的溶解作用形成的次生脉状矿床。岩相和同位素~(87)Xr/~(86)Xr的分析以及地质证据证实了天青石矿层的蒸发成因。
The azure-barite deposits in the Andes Mountains outside Neuquen, Argentina, in the Midwest were formed in the Early Cretaceous. The deposit is located in the Mesozoic stratigraphic distribution area of the Asian Andes and has obvious stratigraphic characteristics related to evaporite facies. Depositional sequence of the geological evolution of the study revealed the temporal and spatial location of evaporite facies. Celestite - barite deposit is mainly controlled by the formation, and the regional distribution of the deposit depends on the regional structure. According to the characteristics and genesis of the deposit, they are considered to belong to three types: (1) celestite bedded deposits of the same origin as the evaporites; (2) due to the growth and dissolution of stalactites, (3) secondary vein deposits formed by the dissolution of barium-enriched water after reactivation. The analysis of lithofacies and isotope ~ (87) Xr / ~ (86) Xr and geological evidence confirm the genesis of the celestite deposit.