The Qingzhen reaction, a fine‐grained mineral assemblage associated with djerfisherite in some EH3 chondrites: Alteration on the EH parent body

Journal article

Enstatite chondrites formed under extremely reducing conditions in the protoplanetary disk. They are derived from two or more parent bodies, EH and EL, and both EH and EL groups contain petrologic type 3–6 samples. The rare lithophile‐ and halogen‐bearing sulfide, djerfisherite, occurs in low abundance in enstatite chondrites, most frequently in the EH3 chondrites. In some EH3 chondrites, but not in EL chondrites, djerfisherite is associated with a fine‐grained mineral assemblage, termed the “Qingzhen Reaction,” which has previously been interpreted as an alteration product of djerfisherite. The Qingzhen Reaction is notable as perhaps the only record of fluid‐mediated alteration on the EH parent body. In this study, we undertook a high‐resolution chemical and mineralogical analysis of the Qingzhen Reaction and its djerfisherite host, in order to determine its composition, relationship to djerfisherite and its formation environment. We show that the Qingzhen Reaction is an alteration product of djerfisherite, predominantly comprised of porous troilite with remnant djerfisherite. Trace quantities of halite and (likely) sphalerite are also present. We suggest that the Qingzhen Reaction formed by the interaction of an anhydrous fluid with djerfisherite on the EH parent body.

Authors: Mc Ardle, P; Jones, RH; Daly, L; Tartèse, R; Clay, PL

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Wiley
• Journal: Meteoritics & Planetary Science
• Publication date: 2025-11-19
• Acceptance date: 2025-11-03
• DOI: 10.1111/maps.70073
• EISSN: 1945-5100
• ISSN: 1086-9379
• Language: English