华北克拉通沉积矿产与地球环境演变的关系^*

Relationship between sedimentary deposits and Earth environment evolution of North China Craton

摘要

华北克拉通广泛发育铁、锰、磷、镁、硼、铝等沉积类矿产,时间范围包括新太古代、古—中元古代及古生代和中生代,其形成规律与华北克拉通的形成与演化、大气—海洋环境的演变以及生物进化等重大事件密切有关。作者从华北克拉通铁、锰、磷、镁、硼、石墨、铝等沉积类矿产的时空展布、矿床地质和地球化学特征的角度,结合华北克拉通形成与演化及地球表生环境演变,综合分析了华北克拉通地区有关沉积矿产的分布规律及其与表生重大地质事件之间的关系。研究表明,新太古代大范围阿尔戈玛型BIF铁矿与古海洋整体缺氧环境有关; 古元古代苏必利尔型铁矿、沉积—变质磷矿、石墨矿、菱镁矿及硼矿等巨量成矿与大氧化事件相耦合,而石墨与磷矿的产出还反映了生物的大规模活动,菱镁矿与硼镁铁矿是干旱气候条件的反映; 中元古代沉积锰矿、铁矿和磷矿的明显富集,可能与中元古代海洋局部升氧事件有关; 石炭纪—二叠纪大规模铝土矿与晚古生代冰期在时间上相吻合。

Abstract

Sedimentary deposits such as iron,manganese,phosphorus,magnesium,boron and aluminum were widely developed in the North China Craton,spanning geological periods from the Neoarchean,Paleoproterozoic,to Paleozoic and Mesozoic. Their formation mechanism are closely linked to the formation and evolution of the North China Craton,atmospheric-marine environmental changes, and biological evolution. The large scale Algoma-type BIF iron deposit in the Neoarchean was related to the overall anoxic environment of the ancient ocean. The large-scale Paleoproterozoic Superior-type iron deposit,depositional-metamorphic phosphate,graphite,magnesite and boron deposit was coupled with the great oxidation event. The output of graphite and phosphate deposits reflected the large-scale biological activities. The magnesite and ludwigite are the products of arid climate conditions. The accumulation of manganese and iron deposit in the Mesoproterozoic sediments may be related to the local oxygen rise event in the Mesoproterozoic ocean. The Carboniferous-Permian bauxite deposits in North China Craton coincide with the late Paleozoic ice age in time. Based on studies of the spatial and temporal distribution features of iron,manganese,phosphorus,magnesium,boron,graphite,aluminum and other sedimentary deposits in the North China Craton,the geological and geochemical characteristics of the deposits,the formation and evolution of the North China Craton and the evolution of the earth’s epigenetic environment,the paper analyzes the distribution regularities of the relevant sedimentary deposits in the North China Craton and the relationship between the deposits and the major epigenetic geological events.

关键词

沉积矿产 / 大规模成矿 / 成矿规律 / 地球环境演变 / 华北克拉通

Key words

sedimentary deposit / large-scale mineralization / metallogenic regularity / earth environment evolution / North China Craton

基金资助

*国家自然科学基金项目(编号: 42302073,42150104)和国家重点研发计划项目(编号: 2022YFC2903502)联合资助