全球早白垩世大规模岩浆活动、铁矿床形成及与气候变化的可能耦合关系

The possible coupling relationship among large-scale magmatic activity,iron deposit formation and global climate change in the Early Cretaceous

地球系统科学是当今地球科学的研究前缘,早白垩时期全球气候经历了巨大的变化,前人为此做了大量的研究工作,但就铁矿形成与环境变化方面的研究还鲜见人提及。本文针对早白垩世大规模岩浆活动、铁矿成因、温室气体的释放及对气候变化的可能耦合关系做探索性的研究工作。本文主要通过大数据统计、整理分析、制图对比等科学手段,论证早白垩世各重要地质事件之间的耦合关系。发现早白垩世的大规模岩浆活动和铁矿爆发巅峰期、陆相红层的出现有着非常吻合的时间一致性。推测早白垩世时期大规模岩浆活动以及铁矿床的形成,释放大量CO_(2)温室气体。大气中CO_(2)温室气体含量急剧增加,导致大气环境温度升高,Fe2+变成Fe3+导致了大陆红层的形成;大气中CO_(2)温室气体含量急剧增加也导致了大气中氧气含量变低,致使后生生物为了适应这种极端环境气候个体趋向于小型化。因此,铁矿床爆发式成矿作用间接地导致了当时气候环境变化和生物演化方向。在当今面临的全球变暖的大环境下,我们更要加深了解和我们当代很相似的晚中生代时期,以便更加主动的应对以后的气候环境变化和生物发展。

Earth system science is the research frontier of earth sciences.The global climate has undergone tremendous changes in the Early Cretaceous Period.Predecessors have made detailed scientific research on environmental changes in Cretaceous,but the few have done research about the formation of iron deposits'impact of the environment.This article mainly makes exploratory study on the large-scale magmatism,the formation of iron deposits,the release of greenhouse gases,and the possible coupling relationship of climate change in the Early Cretaceous.Meanwhile,this study mainly demonstrates the coupling relationship between the mentioned important geological events of the Early Cretaceous through big data statistics,collation analysis,mapping comparison and other scientific tools.It is found that large-scale magmatism,massive iron deposits'formation,and the appearance of continental red layers in the earth's crust are consistent in space-time.We think large-scale magmatism and massive iron deposits'formation will result in a mount of CO_(2) greenhouse gases emission.It,therefor,has caused the global temperature to rise.With the rising temperature in the atmosphere,Fe2+changes to Fe3+in sedimentary rocks,resulting in the formation of a red layer during Early Cretaceous.At the same time,the CO_(2) content in the atmosphere increased sharply,and the oxygen content degreased relatively.So,in order to adapt to this extreme environmental change,metazoans evolved to be smaller.Under the global warming environment,we face today,we have to learn a lesson from Early Cretaceous situation.So,we can respond more wisely to climate change and human's development in the future.