Apatite, a major hydrous mineral in Martian meteorites, has the potential to reveal history of volatiles on Mars. Here we report the H and Cl isotopic systematics of apatite from the enriched basaltic shergottite Northwest Africa (NWA) 8657 to better understand the processes influencing volatiles at or near the Martian (sub)surface. The apatite in NWA 8657 has the highest reported δD value (up to 6,509‰) of any phosphates in Martian meteorites. The positive correlation between the H₂O contents (72–2,251 ppm) and δD values (3,965–6,509‰) as well as between the Cl contents (1.28–6.17wt%) and δ³⁷Cl values (−1.7–4.0‰) in NWA 8657 apatite are consistent with mixing between volatiles derived from the Martian mantle and meteoric water/fluid. The D‐ and ³⁷Cl‐enrichment of apatite in NWA 8657 implies isotopic exchange with subsurficial fluids during postcrystallization hydrothermal event(s).

中文翻译：

---

火星表面上的氘和富含37的氯的流体：来自富集的玄武岩斜方锰矿西北非洲8657的证据

磷灰石是火星陨石中的主要含水矿物，具有揭示火星上挥发物历史的潜力。在这里，我们报告了来自西北非洲丰富的玄武岩黑云母（NWA）8657的磷灰石的H和Cl同位素系统，以便更好地了解影响火星表面（或附近）的挥发物的过程。在火星陨石中，NWA 8657中的磷灰石报告的δD值最高（高达6,509‰）。为H之间的正相关性_2分O含量（72-2,251 PPM）和δD值（3,965-6,509‰）以及在氯含量之间（1.28-6.17wt％）和δ ^37个（-1.7-4.0‰）CI值NWA 8657中的磷灰石与火星地幔中的挥发物与流水/流体之间的混合相一致。D和³⁷NWA 8657中磷灰石的Cl富集意味着在结晶后的热液事件期间与地下岩浆流体进行了同位素交换。