Hokkaido University · 물리·천문학
Noriyuki Kawasaki 교수의 연구실은 태양계 초기의 소행성과 극저온에서 형성된 성분들을 분석하여 태양계 형성과 진화 과정을 규명하는 데 초점을 맞추고 있습니다. 주로 희토류를 포함한 고온에서 형성된 Ca-Al-rich 인클루전스(CAIs)와 수소화 반응에 의해 생성된 탄소질 흑성석형 혼합물의 산화물 동위원소 조성을 정밀 분석함으로써, 태양계 내부에서의 물질 이동과 화학적 변화를 추적합니다. 특히, 이온 질량 분석기(SIMS)를 활용한 고해상도 동위원소 분석 기법을 바탕으로, 초기 태양계의 기체 분위기와 암석 형성 조건을 재구성하고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
TS34 is a Type B1 Ca-Al-rich inclusion (CAI) from the Allende CV3 chondrite, consisting of spinel, melilite, Ti-Al-rich clinopyroxene (fassaite) and minor anorthite in an igneous texture. Oxygen and magnesium isotopic compositions were measured by secondary ion mass spectrometry in spots of known chemical composition in all major minerals in TS34. Using the sequence of formation from dynamic crystallization experiments and from chemical compositions of melilite and fassaite, the oxygen isotopic
The extraterrestrial materials returned from asteroid (162173) Ryugu consist predominantly of low-temperature aqueously formed secondary minerals and are chemically and mineralogically similar to CI (Ivuna-type) carbonaceous chondrites. Here, we show that high-temperature anhydrous primary minerals in Ryugu and CI chondrites exhibit a bimodal distribution of oxygen isotopic compositions: <sup>16</sup>O-rich (associated with refractory inclusions) and <sup>16</sup>O-poor (associated with chondrul
Abstract– Different oxygen isotopic reservoirs have been recognized in the early solar system. Fluffy type A Ca‐Al‐rich inclusions (CAIs) are believed to be direct condensates from a solar nebular gas, and therefore, have acquired oxygen from the solar nebula. Oxygen isotopic and chemical compositions of melilite crystals in a type A CAI from Efremovka CV3 chondrite were measured to reveal the temporal variation in oxygen isotopic composition of surrounding nebular gas during CAI formation. The
Abstract Coarse‐grained, igneous Ca‐Al‐rich inclusions (CAIs) in CV chondrites formed through multiple melting events. We conducted in situ O‐isotope analysis and Al‐Mg systematics by secondary ion mass spectrometry of relict and overgrown minerals from a partial melting event in an Allende Type B CAI, Golfball. Golfball has a Type B CAI bulk composition and a unique structure: a fassaite‐rich mantle enclosing a melilite‐rich core. Many of the blocky melilite crystals in the core have irregularl
Abstract Al–Mg mineral isochron studies using secondary ion mass spectrometry (SIMS) have revealed the initial 26 Al/ 27 Al ratios, ( 26 Al/ 27 Al) 0 , for individual Ca‐Al‐rich inclusions (CAIs) in meteorites. We find that the relative sensitivity factors of 27 Al/ 24 Mg ratio for SIMS analysis of hibonite, one of the major constituent minerals of CAIs, exhibit variations based on their chemical compositions. This underscores the critical need for using appropriate hibonite standards to obtain
