Ray Soumya, Garvie Laurence A J, Rai Vinai K, Wadhwa Meenakshi
School of Earth and Space Exploration, Arizona State University, Tempe, 85287, USA.
Center for Meteorite Studies, Arizona State University, Tempe, 85287, USA.
Sci Rep. 2021 Nov 19;11(1):22552. doi: 10.1038/s41598-021-99160-9.
Iron isotopes record the physical parameters, such as temperature and redox conditions, during differentiation processes on rocky bodies. Here we report the results of a correlated investigation of iron isotope compositions and silicon contents of silicon-bearing metal grains from several aubritic meteorites. Based on their Fe isotopic and elemental Si compositions and thermal modelling, we show that these aubrite metals equilibrated with silicates at temperatures ranging from ~ 1430 to ~ 1640 K and likely sampled different depths within their asteroidal parent body. The highest temperature in this range corresponds to their equilibration at a minimum depth of up to ~ 35 km from the surface of the aubrite parent body, followed by brecciation and excavation by impacts within the first ~ 4 Myr of Solar System history.
铁同位素记录了岩石天体分化过程中的物理参数，如温度和氧化还原条件。在此，我们报告了对来自几块紫苏辉石陨石的含硅金属颗粒的铁同位素组成和硅含量进行相关研究的结果。基于它们的铁同位素和元素硅组成以及热模拟，我们表明这些紫苏辉石金属在温度范围约为1430至1640K时与硅酸盐达到平衡，并且可能在其小行星母体内部的不同深度进行了采样。该温度范围内的最高温度对应于它们在距紫苏辉石母体表面至少约35公里的最小深度处达到平衡，随后在太阳系历史的前约4百万年内因撞击而发生角砾岩化和挖掘。
