@article{9d7b99d530684118ac50bb7e81164a54,
title = "Water on Mars: Insights from apatite in regolith breccia Northwest Africa 7034",
abstract = "Determining the source of planetary water from the hydrogen isotope compositions of crustal samples is complicated by the overprinting of isotopically diverse source material by geologic and atmospheric processes. As Mars has no plate tectonics, crustal material, which may have isotopically exchanged with the martian atmosphere, is not recycled into the mantle keeping the water reservoirs in the mantle and atmosphere mostly isolated, buffered by the crust. As the only known martian samples that are regolith breccias with a composition representative of the average crust of Mars, Northwest Africa (NWA) 7034 and its paired stones provide an important opportunity to investigate the water content and hydrogen isotope composition of the martian crust. In particular, apatites in distinct clasts as well as the brecciated matrix of NWA 7034 record a complex history including magmatic and impact processes, and exchange with crustal fluids.",
keywords = "H-isotopes, NWA 7034, apatite, crustal fluid exchange, martian crust, regolith breccia",
author = "Jemma Davidson and Meenakshi Wadhwa and Hervig, {Richard L.} and Alice Stephant",
note = "Funding Information: Funding: This work was supported by the NASA Solar System Workings grant NNX16AT37G to M.W. Funding Information: The authors thank Ken Domanik for assistance with the Cameca SX-100 EPMA at the University of Arizona, and Axel Wittmann for assistance with the JEOL JXA-8530F EPMA and Lynda Williams for assistance with the Cameca IMS-6f SIMS, both at Arizona State University. We are grateful to Laurence Garvie for assistance with sample preparation of the NWA 7034 samples. This manuscript was significantly improved by comments from two anonymous reviewers and the editorial expertise of R. Dasgupta. We acknowledge the use of facilities within the Eyring Materials Center at Arizona State University supported in part by NNCI-ECCS-1542160 . We acknowledge NSF EAR 1352996 for support of the ASU SIMS facility. Funding Information: The authors thank Ken Domanik for assistance with the Cameca SX-100 EPMA at the University of Arizona, and Axel Wittmann for assistance with the JEOL JXA-8530F EPMA and Lynda Williams for assistance with the Cameca IMS-6f SIMS, both at Arizona State University. We are grateful to Laurence Garvie for assistance with sample preparation of the NWA 7034 samples. This manuscript was significantly improved by comments from two anonymous reviewers and the editorial expertise of R. Dasgupta. We acknowledge the use of facilities within the Eyring Materials Center at Arizona State University supported in part by NNCI-ECCS-1542160. We acknowledge NSF EAR 1352996 for support of the ASU SIMS facility. Funding: This work was supported by the NASA Solar System Workings grant NNX16AT37G to M.W. Publisher Copyright: {\textcopyright} 2020 Elsevier B.V.",
year = "2020",
month = dec,
day = "15",
doi = "10.1016/j.epsl.2020.116597",
language = "English (US)",
volume = "552",
journal = "Earth and Planetary Science Letters",
issn = "0012-821X",
publisher = "Elsevier",
}