Decorah
| Crater Name | Location | Latitude | Longitude | Diameter (km) | Age (Ma) | Exposed | Drilled | Target Rock** | Bolide Type*** |
|---|---|---|---|---|---|---|---|---|---|
| Decorah | United States | N 43° 19' | W 91° 46' | 5.5 | ~467-464 | N | Y | S | - |
References |
Bergstrom, S.M., Schmitz, B., Liu, H.P., Terfelt, F., and McKay, R.M. (2018) High-resolution δ 13 C org
chemostratigraphy links the Decorah impact structure and Winneshiek Konservat-Lagerstätte to the
Darriwilian (Middle Ordovician) global peak influx of meteorites. Lethaia 51: 504–512 .
|
French, B.M., McKay, R.M., Liu, H.P., Briggs, D.E., and Witzke, B.J. (2018) The Decorah structure, northeastern
Iowa: geology and evidence for formation by meteorite impact. GSA Bull 130:2062–2086. |
| * pre-1977 K-Ar, Ar-Ar and Rb-Sr ages recalculated using the decay constants of Steiger and Jager (1977) Ages in millions of years (Ma) before present. ** Abbreviations: C - Crystalline Target; C-Ms - Metasedimentary Target; M - Mixed Target (i.e.sedimentary strata overlying crystalline basement); S - sedimentary target (i.e. no crystalline rocks affected by the impact event). From Osinski. G. R., Spray J. G., and Grieve R. A. F. 2007. Impact melting in sedimentary target rocks: A synthesis. In The Sedimentary Record of Meteorite Impacts, Geological Society of America Special Paper. Editors: Evans K. Horton W., King D., Morrow J., and Warme J. Geological Society of America: Boulder, in press. ***From Koeberl,C. Identification of meteoritic components in impactites. 1998, Koeberl, C. The Geochemistry and Cosmochemistry of Impacts. 2007 and PASSC Files. (IAB, IIIAB, IIIB, IIID - Iron Meteorite) |