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 sec...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 δ^(56/54)Fe ranging from -2.44‰ to +0.69‰are associated with sulfidesilicate melt segregation,while secondary sulfides with δ^(56/54)Fe values between -1.83‰ and -0.14‰ are linked to aqueous alteration.Overall,the Ni content of the grains is positively correlated with δ^(56/54)Fe.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.展开更多
0 INTRODUCTION Changbaishan volcanism,located on the border of China and North Korea,has been a subject of extensive research due to its unique geological features and active volcanic history(Wan et al.,2024).Two prim...0 INTRODUCTION Changbaishan volcanism,located on the border of China and North Korea,has been a subject of extensive research due to its unique geological features and active volcanic history(Wan et al.,2024).Two primary models have been proposed to explain the origin of Changbaishan volcanism(CV).展开更多
Water is essential for the formation of a magmatic arc by lowering the melting temperature of materials in the mantle wedge.As such,it is logical to attribute the absence of a magmatic arc to insufficient water releas...Water is essential for the formation of a magmatic arc by lowering the melting temperature of materials in the mantle wedge.As such,it is logical to attribute the absence of a magmatic arc to insufficient water released from the subducting plate,although a number of other factors may cause volcanic arc quiescence as well,such as a slab window or flat slab subduction.In this contribution,we present a possible but testable correlation between the occurrence of a magmatic arc and seamount subduction in light of bathymetric data obtained near trenches.This correlation,if it holds true,in turn means that a magmatic arc is unlikely to occur when the subducting slabs have not been severely fractured and that one of the main reasons for excluding effects such as the slab window or flat slab subduction may be that the plate is not accompanied by seamounts.Therefore,the role that seamount subduction plays in recycling water back into the mantle deserves more attention from the earth sciences community.展开更多
基金supported by the National Science Foundation of China(Nos.42225202 and 41827802)。
文摘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 δ^(56/54)Fe ranging from -2.44‰ to +0.69‰are associated with sulfidesilicate melt segregation,while secondary sulfides with δ^(56/54)Fe values between -1.83‰ and -0.14‰ are linked to aqueous alteration.Overall,the Ni content of the grains is positively correlated with δ^(56/54)Fe.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.
基金support from the National Natural Science Foundation of China(No.42276049)。
文摘0 INTRODUCTION Changbaishan volcanism,located on the border of China and North Korea,has been a subject of extensive research due to its unique geological features and active volcanic history(Wan et al.,2024).Two primary models have been proposed to explain the origin of Changbaishan volcanism(CV).
基金This work was funded by the National Natural Science Foundation of China(Grant Nos.91858205 and 91858212).
文摘Water is essential for the formation of a magmatic arc by lowering the melting temperature of materials in the mantle wedge.As such,it is logical to attribute the absence of a magmatic arc to insufficient water released from the subducting plate,although a number of other factors may cause volcanic arc quiescence as well,such as a slab window or flat slab subduction.In this contribution,we present a possible but testable correlation between the occurrence of a magmatic arc and seamount subduction in light of bathymetric data obtained near trenches.This correlation,if it holds true,in turn means that a magmatic arc is unlikely to occur when the subducting slabs have not been severely fractured and that one of the main reasons for excluding effects such as the slab window or flat slab subduction may be that the plate is not accompanied by seamounts.Therefore,the role that seamount subduction plays in recycling water back into the mantle deserves more attention from the earth sciences community.
