Evidence for a spatially extensive hydrothermal system at the Ries impact structure, Germany

H. M. Sapers, G. R. Osinski, R. L. Flemming, E. Buitenhuis, N. R. Banerjee, L. L. Tornabene, S. Blain, J. Hainge

Research output: Contribution to journalArticlepeer-review

14 Scopus citations

Abstract

The ~15 Ma, 26 km diameter Ries impact structure in south-central Germany was one of the first terrestrial impact structures where evidence of impact-associated hydrothermal alteration was recognized. Previous studies suggested that pervasive, high-temperature hydrothermal activity was restricted to the area within the “inner ring” (i.e., the crater-fill impactite units). Here we present mineralogical evidence for localized hydrothermal activity in the ejecta beyond the crater rim in two previously unstudied settings: a pervasively altered lens of suevite ejecta directly overlying the Bunte Breccia at the Aumühle quarry; and suevite ejecta at depth overlain by ~20 m of lacustrine sediments sampled by the Wörnitzostheim 1965 drill core. A comprehensive set of X-ray diffraction analyses indicates five distinct alteration regimes (1) surficial ambient weathering characterized by smectite and a minor illitic component; (2) locally restricted hydrothermal activity characterized by an illitic component and minor smectite; (3) hydrothermal activity at depth characterized by smectite, a minor illitic component, and calcite; (4) hydrothermal activity at depth characterized by smectite, a minor illitic component, calcite, zeolites, and clinochlore; and (5) pervasive hydrothermal activity at depth characterized by smectite, a minor illitic component, and minor clinochlore. These data spatially extend the Ries postimpact hydrothermal system suggesting a much more extensive, complex, and dynamic system than previously thought. Constraining the mineralogical alteration regimes at the Ries impact structure may also further our understanding of impact-associated phyllosilicate formation on Mars with implications for climate models and habitability.

Original languageEnglish (US)
Pages (from-to)351-371
Number of pages21
JournalMeteoritics and Planetary Science
Volume52
Issue number2
DOIs
StatePublished - Feb 1 2017
Externally publishedYes

ASJC Scopus subject areas

  • Geophysics
  • Space and Planetary Science

Fingerprint

Dive into the research topics of 'Evidence for a spatially extensive hydrothermal system at the Ries impact structure, Germany'. Together they form a unique fingerprint.

Cite this