Carbon and oxygen isotope study of carbonates from highly shocked clasts of the polymict breccia of the Haughton Crater (Canada)

التفاصيل البيبلوغرافية
العنوان: Carbon and oxygen isotope study of carbonates from highly shocked clasts of the polymict breccia of the Haughton Crater (Canada)
المؤلفون: Agrinier, P, Martinez, I, Javoy, M, Schaerer, U
المصدر: Lunar and Planetary Inst., International Conference on Large Meteorite Impacts and Planetary Evolution.
بيانات النشر: United States: NASA Center for Aerospace Information (CASI), 1992.
سنة النشر: 1992
مصطلحات موضوعية: Astrophysics
الوصف: It is known that the release of volatiles on impact is an important controlling factor in cratering processes in carbonate terranes and in the mobility of chemical elements. In order to assess the nature and the role of carbon- and oxygen-bearing volatiles during impact-induced metamorphism of sedimentary rocks, the C-13/C-12 and O-18/O-16 ratios and carbonate contents were determined for 30 shocked clasts from the Haughton Crater polymict breccia as well as for some unshocked carbonates from the sedimentary cover adjacent to the crater. Shock-induced CO2 loss during decarbonation of calcite is known to be a function of peak pressure and ambient partial pressure of the volatile species. In our clast samples, shocked from 20 to 60 GPa, we expect about 20 to 100 percent CO2 loss and preferential depletion in C-13 and O-18 in the residual carbonate. Rayleigh model (progressive loss of CO2) and batch model (single-step loss of CO2) curves for this depletion are shown. The magnitudes of the C-13 and O-18 depletions increase with the increase of the CO2 loss. In addition, the isotopic depletions should be correlated with an enrichment in CaO and MgO in the residual solid.
نوع الوثيقة: Report
اللغة: English
Relation: International Conference on Large Meteorite Impacts and Planetary Evolution
URL الوصول: https://ntrs.nasa.gov/citations/19930000925
رقم الانضمام: edsnas.19930000925
قاعدة البيانات: NASA Technical Reports