Impact - Generated Hydrothermal Circulation and Metasomatism of the Rochechouart Astrobleme

Rochechouart Hydrothermal Overprint: Disentangling the Timing of Events through Ar-ar Dating

Introduction: There is a growing interest in the thermal evolution and fluid behavior of impact structures in the context of their possible influence on emergence of life both in the Early Earth and on other Planetary Bodies. This is largely related to hydrothermal mechanisms at work during the cooling of the hot materials produced and deposited in impact craters. Yet most of the research in th...

High Temperature Hydrothermal Fluid Flow within the Sub-Crater Environment of the Rochechouart Impact Structure: Observations from a

Re-evaluating the Rochechouart Impactites: Petrographic Classification, Hydrothermal Alteration and Evidence for Carbonate Bearing

Introduction: The Rochechouart impact structure is a deeply eroded, late Triassic impact site located in south-central France [1,2]. Rochechouart impactites comprise five main lithological units from the base of the structure upwards, originally described as follows: unit 1) shocked autochthonous basement rock; unit 2) finely crystalline melt rock; unit 3) red 'welded' breccia/suevite; unit 4) ...

Hydrothermal Alteration of the Impactites at the Icdp Drill Site Yax-1

Introduction. About 100 m of impactites (suevitetype breccias) have been drilled at the ICDP drill site Yax-1 within the Chicxulub impact structure (see [1] for more information). Post-impact hydrothermal alteration including alkali metasomatism and devitrification of impact melt glass has significantly modified the mineralogy and chemistry of the impact breccia lithologies. Hydrothermal altera...

A Triassic/jurassic Boundary Age for the Rochechouart Impact Structure (france)

Introduction: The age of the ~23 km in diameter Rochechouart impact structure, France, hosted by Precambrian to Paleozoic (Variscan) crystalline rocks of the northwestern French Massif Central, has long time been a matter of debate. Previous studies, including K-Ar, Rb-Sr, apatite and glass fission track, as well as paleomagnetic dating (see [1] for summary of ages), resulted in a broad (Middle...