摘要
元古代是一个重要成矿期。又是全球成矿背景发生根本性变化的时期。华北元古界中有丰富的矿产资源。它们的形成除受全球背景制约外,还受局部条件所影响。因此,呈现出区域成矿特殊性。全球性成矿背景发生转变的时期,在华北古陆主要表现在吕梁运动(1850Ma)前后。
Proterozoic is an important minerogenic epoch and also a turning period of the global minerogenic background in geological history. In North China, lots of mineral resources occurred in Proterozoic, and their minerogenic processes were controlled by both the global background and the regional or local conditions. The analytical results of the sedimentation evolution, the chemical characteristics, and the types of mineral deposits all point to the conclusion that in North China the abruptly turning point of the global minerogenic background of Proterozoic might have mainly occurred just before and after Luliang orogeny (1850Ma). To cite two examples:during that time, the chemical composition of the atmorsphere changed from CO_2-N_2 type to N_2-CO_2-O_2 type, and the pH of the sea water changed from acidic to alkaline.
出处
《矿床地质》
CAS
CSCD
北大核心
1991年第1期52-58,共7页
Mineral Deposits
