Noble gases and nitrogen in CV3 chondrite Bukhara
Ramakant R. Mahajan, Shuhrat A. Ehgamberdiev, Sekhar Naik
Planetary and Space Science
In Press, Journal Pre-proof, Available online 1 September 2021
“Highlights
• Noble gas and nitrogen isotopic were studied in CV3 chondrite Bukhara.
• We calculate cosmic ray exposure age of 22.6 ± 4.0 Ma from noble gases.
• Trapped nitrogen is distinct compared with CV3 chondrites.”
“We investigated noble gas (He, Ne, Ar, Kr and Xe) and nitrogen isotopic composition in the carbonaceous chondrite Bukhara (CV3). This is the first report of N and noble gases measured in the same aliquot of bulk sample among the CV3 chondrites. Isotopic compositions of noble gases are mixtures of solar wind and Q-gases. We derive cosmic ray exposure (CRE) age of 22.6 ± 4.0 Ma from cosmogenic 21Ne and 38Ar for Bukhara. Nitrogen abundance observed in Bukhara is lowest compared with the data from CV3 chondrites. We estimate the trapped nitrogen composition of δ15N = + 10.9 ± 1.6‰ for Bukhara, distinct from average (δ15N = - 16.3 ± 1.5‰) in the bulk CV3 chondrites. Bukhara shows signature of heavy nitrogen, which is distinct than the solar wind (SW) and Q-gas. Trapped nitrogen is mixture of the components, SW, Q and comet. It is observed that there is no correlation of nitrogen composition with N content in the CV3 chondrites.”
