Kanoko Kurihara, Norika Numa, Sota Niki, Mai Akamune, Masaki Nakazato, Shuji Yamashita, Shoichi Itoh, Takafumi Hirata
{"title":"Elemental and Isotopic Signatures of Individual Particles in Chondrite Matrix using Inductively Coupled Plasma Mass Spectrometry","authors":"Kanoko Kurihara, Norika Numa, Sota Niki, Mai Akamune, Masaki Nakazato, Shuji Yamashita, Shoichi Itoh, Takafumi Hirata","doi":"10.2343/geochemj.gj23015","DOIUrl":null,"url":null,"abstract":"Elemental and isotopic analyses of individual submicron-sized particles in chondrite matrix were made by an inductively coupled plasma time-of-flight mass spectrometer (ICP-TOF-MS) and a multiple collector-ICP-MS equipped with high-time resolution ion counters (HTR-MC-ICP-MS). The particles were collected from Allende CV3 chondrite through a laser ablation-in-liquid (LAL) technique. Firstly, the abundances for four major elements (Si, Al, Mg, and Fe) were determined on total 6086 particles, indicating that the Allende matrix is a mixture of submicron-sized particles made mainly of olivine, pyroxene, spinel, Fe–Ni sulfide and Fe–Ni metal, consistent with the predicted major constituent minerals by nebular condensation model. The major elemental compositions revealed that Fe–Ni particles are minor components (about 0.3% in number fraction) in the Allende matrix. Then, to estimate the origin of these metallic particles, abundances for Ni and two minor elements (Os and Pt) were measured. Total 10417 particles of Ni–Os–Pt bearing particles were also found in the chondrite matrix. Majority of the particles were enriched in Ni. Os and Pt were present as separated particles, and no particles with presence of both the Os and Pt were found. Finally, with the HTR-MC-ICP-MS technique, 195Pt/194Pt value was measured on total 1545 particles. The resulting 195Pt/194Pt value agreed with the solar composition within analytical uncertainties. This lack in isotopic anomalies of the 195Pt/194Pt can be explained either by majority of the Pt nuggets being produced from uniform reservoir in the solar system or by Pt being isotopically homogenized prior to the formation of the solar nebula.","PeriodicalId":12682,"journal":{"name":"Geochemical Journal","volume":"44 1","pages":"0"},"PeriodicalIF":1.0000,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Geochemical Journal","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.2343/geochemj.gj23015","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOCHEMISTRY & GEOPHYSICS","Score":null,"Total":0}
引用次数: 0
Abstract
Elemental and isotopic analyses of individual submicron-sized particles in chondrite matrix were made by an inductively coupled plasma time-of-flight mass spectrometer (ICP-TOF-MS) and a multiple collector-ICP-MS equipped with high-time resolution ion counters (HTR-MC-ICP-MS). The particles were collected from Allende CV3 chondrite through a laser ablation-in-liquid (LAL) technique. Firstly, the abundances for four major elements (Si, Al, Mg, and Fe) were determined on total 6086 particles, indicating that the Allende matrix is a mixture of submicron-sized particles made mainly of olivine, pyroxene, spinel, Fe–Ni sulfide and Fe–Ni metal, consistent with the predicted major constituent minerals by nebular condensation model. The major elemental compositions revealed that Fe–Ni particles are minor components (about 0.3% in number fraction) in the Allende matrix. Then, to estimate the origin of these metallic particles, abundances for Ni and two minor elements (Os and Pt) were measured. Total 10417 particles of Ni–Os–Pt bearing particles were also found in the chondrite matrix. Majority of the particles were enriched in Ni. Os and Pt were present as separated particles, and no particles with presence of both the Os and Pt were found. Finally, with the HTR-MC-ICP-MS technique, 195Pt/194Pt value was measured on total 1545 particles. The resulting 195Pt/194Pt value agreed with the solar composition within analytical uncertainties. This lack in isotopic anomalies of the 195Pt/194Pt can be explained either by majority of the Pt nuggets being produced from uniform reservoir in the solar system or by Pt being isotopically homogenized prior to the formation of the solar nebula.
期刊介绍:
Geochemical Journal is an international journal devoted to original research papers in geochemistry and cosmochemistry. It is the primary journal of the Geochemical Society of Japan. Areas of research are as follows:
Cosmochemistry; Mineral and Rock Chemistry; Volcanology and Hydrothermal Chemistry; Isotope Geochemistry and Geochronology; Atmospheric Chemistry; Hydro- and Marine Chemistry; Organic Geochemistry; Environmental Chemistry.