近日，中国地质大学（武汉）向武团队研究了Aguas Zarcas（CM2）球粒陨石中硫化物中的铁同位素：对母小行星历史的影响。该项研究成果发表在2025年9月23日出版的《地球化学学报》杂志上。

CM球粒陨石包含了对太阳星云形成和演化的宝贵见解，以及影响其母体的二次水性改变过程。

研究组重点分析了Aguas Zarcas （CM2）球粒陨石中的原生和次生硫化物，根据它们的形态、结构和组成来研究其形成机制。此外，研究组还推断出初生硫化物的形成温度在230 ~ 500℃之间，次生硫化物的形成温度在100 ~ 135℃之间。选取具有代表性的颗粒，对其进行了铁同位素测量。

δ^56/54Fe的原生硫化物为2.44‰~ + 0.69‰与硫化物-硅酸盐熔体偏析有关，δ^56/54Fe值在1.83‰和0.14‰与水体蚀变有关。总体而言，晶粒Ni含量与δ^56/54Fe呈正相关。这可能与镍含量的增加导致晶体结构和化学键长度的变化有关。铁同位素为研究碳酸盐球粒陨石母体硫化物的形成和演化提供了新的视角。

附：英文原文

Title: Fe isotopes in sulfides in the Aguas Zarcas (CM2) chondrite: Implications for the history of the parent asteroids

Author: Zhu, Xinqian, Wang, Xinyu, Qian, Cheng, Deng, Kexin, He, Qi, Wang, Zaicong, Zhang, Wen, Yang, Ao, Pan, Fabin, Wu, Xiang

Issue&Volume: 2025-09-23

Abstract: CM chondrites contain valuable insights into the formation and evolution of the solar nebula, as well as the secondary aqueous alteration processes that affected their parent bodies. Our study focuses on primary and secondary sulfides within the Aguas Zarcas (CM2) chondrite, investigating their formation mechanisms based on their morphology, textures, and compositions. Moreover, we infer the formation temperatures of the sulfides from 230 to 500 ℃ for primary and from 100 to 135 ℃ for secondary. We select representative grains and conduct Fe isotope measurements on them. The primary sulfides with δ56/54Fe ranging from 2.44‰ to + 0.69‰ are associated with sulfide–silicate melt segregation, while secondary sulfides with δ56/54Fe values between 1.83‰ and 0.14‰ are linked to aqueous alteration. Overall, the Ni content of the grains is positively correlated with δ56/54Fe. It might be related to the changes in crystal structure and chemical bond lengths due to the increase in nickel content. Fe isotopes provide a new perspective on sulfide formation and the evolution of a carbonaceous chondrite parent body.

DOI: 10.1007/s11631-025-00821-7

Source: https://link.springer.com/article/10.1007/s11631-025-00821-7