Role of water in the formation of the Late Cretaceous Wetumpka impact structure, inner Gulf Coastal Plain of Alabama, USA
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CitationKing, D. T., Ormö, J., Petruny, L. W., & Neathery, T. L. (2006). Role of water in the formation of the Late Cretaceous Wetumpka impact structure, inner Gulf Coastal Plain of Alabama, USA. Meteoritics & Planetary Science, 41(10), 1625-1631.
PublisherThe Meteoritical Society
JournalMeteoritics & Planetary Science
DescriptionFrom the proceedings of the Workshop on the Role of Volatiles and Atmospheres on Martian Impact Craters held on July 11-14, 2005, at the Johns Hopkins University Applied Physics Laboratory.
AbstractThe effect of shallow marine water (30-100 m deep) in the late excavation and early modification stages of a marine-target crater 5 km in diameter, as exemplified by the Late Cretaceous Wetumpka impact structure in Alabama, USA, is manifest in the early collapse of a weak part of the rim. Excavation flow and connate marine water are interpreted to be factors in this collapse. This partial rim collapse catastrophically emplaced an upper-structure-filling unit of broken and redistributed sedimentary target formations, which presently mantles the deeper fallback breccia deposits within the structure. Furthermore, rim collapse flow facilitated the formation of a structurally modified, extrastructure terrain, which is located outside and adjacent to the collapsed rim segment. This extrastructure terrain appears to be the product of extensive slumping of poorly consolidated target sedimentary formations.
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