新疆罗布泊东部发现球粒陨石雨

发布时间：2018-01-13 13:33

本文关键词：新疆罗布泊东部发现球粒陨石雨　出处：《科学通报》2017年21期 　论文类型：期刊论文

【摘要】：新疆罗布泊以东65 km处的三峰山区域发现了陨石(Tuya 002~007)散落区,呈3 km×11 km的椭圆状.散落区内收集到130余块普通球粒陨石,总重超过160 kg,最大的陨石重30 kg,最小的陨石重约15 g.散落区为一南东-北西向分布且陨石样品逐渐增大的椭圆形区域,这意味着陨石从南东向以较低的角度进入地球大气层.除Tuya002(760 g)外,散落区内的陨石可能来自同一次陨石雨,陨石类型为L5,冲击程度为S2,风化程度为W3.Tuya 003的宇宙射线暴露年龄为45.6±4.4 Ma,因此三峰山陨石雨的流星体可能形成于约40 Ma时普通球粒陨石L群母体的破裂事件中.Tuya 002具有和其他三峰山陨石显著不同的外表特征,表面熔壳全部脱落,球粒清晰可见,为L4型普通球粒陨石,样品中有大量的硫酸钙.其宇宙射线暴露年龄为17.0±4.1 Ma,也证明了其不是三峰山陨石雨的产物.三峰山区域陨石的研究表明三峰山区域不是陨石富集区,而是L5普通球粒陨石散落区.因此,需要对其他一些区域的陨石样品进行矿物岩石学、风化特征、宇宙射线暴露年龄和居地年龄的研究,从而确定出新疆及其周边沙漠区域的陨石富集区.
[Abstract]:The meteorite Tuya 002 (007) scattered area was found in Sanfengshan region, 65 km east of Luoppo, Xinjiang. More than 130 ordinary chondrites with a total weight of more than 160 kg and a maximum weight of 30 kg were collected in the scattered area. The smallest meteorite weight is about 15 g. The scattered area is an elliptical area with an east-northwest distribution of meteorite samples and a gradual increase in the size of the meteorite samples. This means that meteorites enter the earth's atmosphere at a lower angle from south to east. Except for Tuya002(760 g, the meteorites in the scattered area may have come from the same meteorite rain, the type of meteorite is L5. The cosmic ray exposure age of W3.Tuya 003 is 45.6 卤4.4 Ma. Therefore, the meteoroids of Sanfengshan meteorite rain may have formed in the rupture event of the ordinary chondrites L group at about 40 Ma. Tuya 002 has distinct appearance characteristics from the other three Fengshan meteorites. The surface melting crust is completely shedding, and the chondrites are clearly visible. They are ordinary chondrites of L4 type, and there is a large amount of calcium sulfate in the samples. The cosmic ray exposure age is 17.0 卤4.1 Ma. It is also proved that it is not the product of Sanfeng Mountain meteorite rain. The study of meteorite in Sanfeng Mountain region shows that Sanfeng Mountain region is not a meteorite rich area, but a L5 common chondrites scattered area. It is necessary to study the mineral petrology, weathering characteristics, cosmic ray exposure age and residence age of meteorite samples from other regions, so as to determine the meteorite accumulation areas in Xinjiang and its surrounding desert areas.
【作者单位】：中国科学院地球化学研究所月球与行星科学研究中心;中国科学院地球化学研究所环境地球化学国家重点实验室;Physical
【基金】：国家自然科学基金(41273080,41473067和41490630)资助
【分类号】：P185.83
【正文快照】： 3.Physical Institute,University of Bern,Sidlerstrasse 5,CH-3012 Bern,Switzerland;4.新疆地质矿产勘查开发局第六地质大队,哈密839000;5.中国科学院大学,北京100049*联系人,E-mail:wangshijie@vip.skleg.cn国家自然科学基金(41273080,41473067和41490630)资助陨石是穿越

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