Enstatite chondrite density, magnetic susceptibility, and porosity
Enstatite chondrite density, magnetic susceptibility, and porosity
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顽辉石球粒陨石密度、磁化率和孔隙率
DOI：
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发表时间：
2010
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通讯作者：
M. Hutson
中科院分区：
文献类型：
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作者：
R. Macke;G. Consolmagno;D. Britt;M. Hutson
摘要：作为我们对陨石物理性质持续调查的一部分，我们测量了23颗顽辉石球粒陨石（ECs）中的41颗石头的颗粒和体积密度、孔隙率和磁化率，这些陨石的质量都大于10g，代表了大多数陨落和所有可用的非南极EC陨石的很大比例。我们的采样包括瀑布和发现的混合。对于瀑布，颗粒密度范围为3.45至4.17 g cm - 3，平均为3.66 g cm - 3；体积密度范围为3.15至4.10 g cm - 3，平均为3.55 g cm - 3；孔隙率范围为0 ~ 12%，大多数小于7%，磁化率（对数单位为10−9 m3 kg−1）为5.30 ~ 5.64，平均为5.47。对于发现，风化降低颗粒和体积密度以及磁化率。平均而言，发现的孔隙度比瀑布高得多。两个EC亚群EH和EL，名义上以总铁含量区分，在所有测量的属性中显示出相似的值，表明两个亚群的大块石头中金属铁含量相似。我们还观察到相当大的陨石内部变化，在大约40 g（大约12 cm3）的尺度上，体积和颗粒密度不均匀。
Abstract– As part of our continuing survey of meteorite physical properties, we measured grain and bulk density, porosity, and magnetic susceptibility for 41 stones from 23 enstatite chondrites (ECs), all with masses greater than 10 g, representing the majority of falls and a significant percentage of all available non‐Antarctic EC meteorites. Our sampling included a mix of falls and finds. For falls, grain densities range from 3.45 to 4.17 g cm−3, averaging 3.66 g cm−3; bulk densities range from 3.15 to 4.10 g cm−3, averaging 3.55 g cm−3; porosities range from 0 to 12% with the majority less than 7%, and magnetic susceptibilities (in log units of 10−9 m3 kg−1) from 5.30 to 5.64, with an average of 5.47. For finds, weathering reduces both grain and bulk densities as well as magnetic susceptibilities. On average, finds have much higher porosity than falls. The two EC subgroups EH and EL, nominally distinguished by total iron content, exhibit similar values for all of the properties measured, indicating similar metallic iron content in the bulk stones of both subgroups. We also observed considerable intra‐meteorite variation, with inhomogeneities in bulk and grain densities at scales up to approximately 40 g (approximately 12 cm3).