Role of water in the formation of the Late Cretaceous Wetumpka impact structure, inner Gulf Coastal Plain of Alabama, USA
Citation
King, 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.Publisher
The Meteoritical SocietyJournal
Meteoritics & Planetary ScienceDescription
From 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.Additional Links
https://meteoritical.org/Abstract
The 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.Type
Proceedingstext
Language
enISSN
1945-5100Scopus Count
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