On the aerodynamic redistribution of chondrite components in protoplanetary disks
On the aerodynamic redistribution of chondrite components in protoplanetary disks
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原行星盘中球粒陨石成分的气动重新分布
DOI：
10.1016/j.icarus.2012.04.022
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发表时间：
2012
期刊：
影响因子：
3.2
通讯作者：
S. Fromang
中科院分区：
文献类型：
--
作者：
E. Jacquet;M. Gounelle;S. Fromang
尽管大致都是太阳成分，原始陨石（球粒陨石）在化学、同位素和岩石学性质方面表现出多样性，特别是碳质和非碳质球粒陨石之间的一阶二分法。我们在这里分析研究了原行星盘中它们的成分（球粒、难熔包裹体、金属/硫化物和基质颗粒）在融入球粒陨石母体之前的动力学。我们发现，受气体阻力影响的固体动力学本质上是由“气固解耦参数”SeqSt/α（无量纲停止时间与湍流参数之比）控制的。当 S 超过 1 时，固体颗粒相对于气体的解耦是显着的。 S 预计会随着时间和日心距离的增加而增加。根据(i)难熔包裹体丰度、(ii)基质比例、(iii)亲石元素丰度和(iv)球粒氧同位素组成，我们提出，当碳质球粒陨石增生时，非基质球粒陨石成分的S<1，而当其他球粒陨石增生时，非基质球粒陨石成分的S>1。这表明碳质球粒陨石的沉积平均早于其他球粒陨石，并且难熔包裹体在遗传上与其宿主碳质球粒陨石有关。
Despite being all roughly of solar composition, primitive meteorites (chondrites) present a diversity in their chemical, isotopic and petrographic properties, and in particular a first-order dichotomy between carbonaceous and non-carbonaceous chondrites. We investigate here analytically the dynamics of their components (chondrules, refractory inclusions, metal/sulfide and matrix grains) in protoplanetary disks prior to their incorporation in chondrite parent bodies. We find the dynamics of the solids, subject to gas drag, to be essentially controlled by the “gas–solid decoupling parameter”S≡St/α, the ratio of the dimensionless stopping time to the turbulence parameter. The decoupling of the solid particles relative to the gas is significant when S exceeds unity. S is expected to increase with time and heliocentric distance. On the basis of (i) abundance of refractory inclusions, (ii) proportion of matrix, (iii) lithophile element abundances, and (iv) oxygen isotopic composition of chondrules, we propose that non-matrix chondritic components had S<1 when carbonaceous chondrites accreted and S>1 when the other chondrites accreted. This suggests that accretion of carbonaceous chondrites predated on average that of the other chondrites and that refractory inclusions are genetically related to their host carbonaceous chondrites.
影响因子：
2.2
作者：
Hezel, Dominik C.;Russell, Sara S.;Kearsley, Anton T.
通讯作者：
Kearsley, Anton T.
影响因子：
5
作者：
A. Stracke;H. Palme;M. Gellissen;C. Münker;T. Kleine;Karin Birbaum;D. Günther;B. Bourdon;J. Zipfel
通讯作者：
A. Stracke;H. Palme;M. Gellissen;C. Münker;T. Kleine;Karin Birbaum;D. Günther;B. Bourdon;J. Zipfel
影响因子：
5.3
作者：
D. Hezel;H. Palme
通讯作者：
D. Hezel;H. Palme