Carbonate Condensates in the Chicxulub Ejecta Deposits from Belize
Abstract
It has long been proposed that large amounts of CO2 released to the atmosphere by impact vaporization of carbonates could trigger greenhouse warming. Recent studies of the Cretaceous/Tertiary Chicxulub impact indicate that large amounts of both carbonate and sulfate were vaporized, although sulfates had a much more dramatic effect on climate in part due to the relatively small ambient sulfate reservoir of the Earth's atmosphere compared to the huge ambient reservoir of CO2. One process that could mitigate the climatic effects of these volatiles is the back reaction of impact generated oxides (CaO and MgO) with CO2 and SO2-SO3 in the vapor plume. Analyses of Chicxulub ejecta deposits from Belize confirm that the proximal ejecta in this locality are dominated by carbonate lithologies and sulfates are extremely rare. Much of the carbonate is in the form of dolomite and calcite spheroids and euhedral dolomite silt matrix. These spheroids and fine-grained matrix may have formed through condensation in the vapor plume, thus sequestering large amounts of impact generated CO2.
- Publication:
-
Lunar and Planetary Science Conference
- Pub Date:
- March 1996
- Bibcode:
- 1996LPI....27.1045P
- Keywords:
-
- BELIZE;
- CRATER: CHICXULUB;
- CRATERS: IMPACT;
- DEPOSITS: EJECTA;
- IMPACTS: CRETACEOUS/TERTIARY DEPOSITS