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专家们估计,在地球存在的30亿年以来,至少形成过15万个直径大于0.8公里的陨石坑,其中直径超过10公里的约有3000多个。立于我国内蒙古的多伦陨石坑的外环直径达170公里,是迄今为止发现的世界上最大,同时又是保存较好的陨石坑之一。这自然引起了国内外科学家们的极大关注。近年来,我国科学科应用X光分析、透射电子显微镜、扫描电镜、能谱分析、K-Ar年龄测定等新方法对多伦陨石坑进行了系统研究,取得了一系列令世人瞩目的新成果。这不仅对了解地球演化历史及寻找新的矿产资源具有重大理论意义和实践意义,同时也对陨击作用本身有了更为深入的了解。那么,通过对多伦陨石坑的最新研究,我们对天下第一坑到底取得了哪些主要的认识呢?
Experts estimate that at least 150,000 craters greater than 0.8 kilometers in diameter have been formed since the Earth's existence of 3.0 billion years, of which about 3,000 more than 10 kilometers in diameter. The outer ring of the Duolun meteorite crater, located in Inner Mongolia, China, has a diameter of 170 km and is by far the largest and the best-preserved one in the world. This naturally aroused great concern of scientists at home and abroad. In recent years, the Department of Science in our country applied X-ray analysis, transmission electron microscopy, scanning electron microscopy, energy spectrum analysis, K-Ar dating and other new methods of the Dolen crater research, made a series of world-renowned new achievements . This not only has great theoretical and practical significance for understanding the evolution history of the earth and finding new mineral resources, but also has a more in-depth understanding of the meteorite impact itself. Well, through the latest research on the Dolmen crater, what are the main understandings we have of the first pit in the world?