碧口古陆周边锰矿找矿分析

前震旦系碧口群,属四川古陆核西北缘,中新元古代发育的岛弧型建造,经晋宁运动碰撞拼贴,组成扬子地台的一部分,本身固结成为古陆。在其周边及东部成带分布了含锰岩系。目前各含锰矿带上的锰矿床,具体层位归属有蓟县纪、震旦纪、寒武纪等之不同认识。经分析研究认为,含锰岩系均属前震旦纪摩大岭复背斜褶皱带（即碧口古陆）之上的盖层型震旦寒武纪沉积,大致应为同一时代,即晚震旦世。由于各带所处地质构造背景、沉积环境的不同,锰矿特征明显有异,南含锰矿带临接扬子地台,为弱还原地质环境相对稳定,以优质锰矿类型为主;北含锰矿带紧邻秦岭地槽,凹陷较深为还原环境,以高磷锰矿为主。在该带含锰岩系的构造岩性有利部位,易形成风化淋积型锰矿床。故在寻找锰矿过程中,应区别对待,注意优质锰矿的辨认,并对本区锰矿找矿标志及找矿方向提出建议。

Search Direction for Manganese Ore in the Surroundings of Presinian Bikou Ancient Land

We set forth different understandings of whether the position of manganese-bearing ore belt belongs to Jixian, Sinian period or Cambrian period in the east and in the surroundings of Presinian Bikou ancient land, the article analysis and research follows that manganese-bearing rock series are the deposits in Sinian-Cambrian period overlying on the Presinian Motianling antichinorium folded belt belonging to the contemporaneous deposit （i. e. , Upper Sinian Series）. Owing to the different geological structural setting and different sedimentary environment, high--quality manganese ore concentrates in the southern belt; while the manganese ore with high phosphorus is located in the northern belt, where infiltration manganese deposit by weathering process formed in the favorable positions for structure and rock series. We also give suggestions about the criteria for ore prospecting and search direction for manganese