Thermal-metamorphic signature of an impact event in the Vredefort dome, South Africa

Other

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

24

Scientific paper

Pseudotachylitic breccias and shock deformation features related to the 2.02 Ga formation of the Vredefort dome by meteorite impact were overprinted by a static metamorphic event, the intensity of which decreased from granulite-facies (T ≥700 °C) in the center of the dome to greenschist-facies (T ≤400 °C) around its margins. Geobarometric estimates of 0.2 0.3 GPa for the metamorphic parageneses indicate some 8 11 km of erosion since the impact event. The strong lateral thermal gradient implied by these P-T results is attributed to the combined effects of differential uplift of mid-crustal rocks heated along a pre-impact geotherm and increased shock heating of the target crust toward the center of the impact structure. We suggest that the exceptionally high grade of metamorphism in the center of the dome may, in part, reflect an elevated regional geothermal gradient of ˜25 °C/km in the target crust due to lingering thermal effects related to the 2.05 2.06 Ga Bushveld magmatic event.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Thermal-metamorphic signature of an impact event in the Vredefort dome, South Africa does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Thermal-metamorphic signature of an impact event in the Vredefort dome, South Africa, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Thermal-metamorphic signature of an impact event in the Vredefort dome, South Africa will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-816475

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.