Kentland - Hypervelocity Impact Crater

Alternate Names
Local Language
Coordinates 40° 45' 16" N; 87° 22' 60" W
Notes
  1. 4 km E of the town of Kentland, Newton County.
Country United States of America
Region Indiana
Date Confirmed 1947
Notes
  1. Confirmed by shatter cones in the limestone of the structure (Dietz, 1947).
Buried? No
Notes
  1. The ring depression has preserved Pennsylvanian coals and most of the structure is covered with a thin veneer of Pleistocene glacial till (Laney and Van Schmus, 1978).
Drilled? Yes
Notes
  1. A total of 2162 m of drilling from 140 holes ranging in depth from 6 to 50 m. In general, the core recoveries were poor (Tudor, 1971).
Target Type Sedimentary
Notes
  1. Structurally complex Ordovician through Pennsylvanian sedimentary sequence, mostly carbonates and shales (Laney and Van Schmus, 1978).
Sub-Type Carbonate, Shale
Apparent Crater Diameter (km) 7 km
Age (Ma) 1 - 300
Notes :
  1. 1-300 Ma based on stratigraphic constraints (Weber et al., 2005). Previous work estimated an age of post-Early Pennsylvanian/pre-Pleistocene (Laney and Van Schmus, 1978). Also see a palaeomagnetic study that indicates a Late Cretaceous pole (Jackson and Van Der Voo, 1986).

Method :
  1. Stratigraphy
Impactor Type Unknown
Notes
  1. Not in literature.

Advanced Data Fields

Notes

Erosion
5
  1. The original ground plane is estimated to be ~ 300 m above the present erosional plane. The crater-fill products are partially preserved and the crater floor at the central uplift is exposed (Laney and Van Shmus, 1978). Erosion is 300 m.
Final Rim Diameter
Unknown
Apparent Rim Diameter
7 km
  1. 6-7 km according to the reevaluation from (Weber, 2013). (Laney and Van Schmus, 1978).
Rim Reliability Index
2
  1. An eroded central uplift, approximately 4 km in diameter, is surrounded by a concentric ring syncline and anticline (Laney and Van Schmus, 1978). 600 meters of stratigraphic uplift (Weber, 2013).
Crater Morphology
Complex
Central Uplift Diameter
4km
Central Uplift Height
Unknown
Uplift Reliability Index
3
Structural Uplift
600 m
Thickness of Seds
Target Age
Palaeozoic
Marine
No
Impactor Type
  1. Not in literature.
Other Shock Metamorphism
Feather features in Qz Shock-twinned zircon
  1. Feather features and shock-twinned zircon (Morrow and Weber, 2009) (Cavosie and Weber, 2019).
Shatter Cones
Yes
  1. Shatter cones, most are few cm's in height, a few are several m's (Gutschich, 1976) (Gutschich, 1983), in almost all lithologies (Dietz, 1947) (Dietz, 1963) in the central uplift. Shatter cones in limestone, shale, and sandstone (Shrock and Malott, 1933). Shatter cones "have developed in all orientations with respect to the bedding planes" (Bucher, 1936). Shatter cones have formed in all lithologies but they are most abundant in the denser carbonate rocks (e.g., in Silurian dolomite; Laney and Van Schmus, 1978). They range in size from 1 to 20 cm and apical angles generally range from 83 to 105° (Laney and Van Schmus, 1978). Shatter cones are developed in association with mesoscopic inhomogeneities like fossil fragments. "Occasional shatter cone segments" occur in polymict breccia from the so-called "Kentland quarry" (Laney and Van Schmus, 1978). According to (Weber, pers. comm., 2011), shatter cones developed only in some beds and not in others. 2-cm fragment of a shatter cone in dolomite (Fig. 2b; Bjornerud, 1998). Megashatter cones (Bunch et al., 1961). Prominently developed in the limestones at the Kentland disturbance are cup-and-cone structures called "shatter-cones" (Dietz, 1947). The shatter cones found at Kentland (Plate 1a; Dietz, 1963). Well-preserved shatter cones (Koeberl and Sharpton, 1993).
Planar Fractures
Yes
  1. Planar microstructures consisting of common open PFs with c(0001) orientation in quartz (Morrow and Weber, 2009).
Planar Deformation Features
Yes
  1. PDF in quartz grains {0001} (Laney and Van Schmus, 1978) "Planar microstructures... consist of ... incipient, partially decorated PDFs with higher index orientations including r{1011} ,  {1122} , s{1121} , x{5161} , and {2131}. The incipient PDFs are commonly truncated by or developed off of longer, through-going PFs, forming 'feather textures'" (Morrow and Weber, 2009).
Diaplectic Glass
No
Coesite
Yes
  1. Coesite in St. Peter sandstone (Cohen et al., 1961). Coesite was detected optically in St. Peter sandstoneand in breccia (Fig. 1; Bunch et al., 1961).
Stisovite
No
Crater Fill
LB
  1. LB in craterfill and dikes noted by (Bjornerud, 1998) (Weber et al., 2013). No melt products or mineralogical evidence for significantly elevated temperatures have been found in the surviving rocks at Kentland (Laney and van Schmus, 1978).
Proximal Ejecta
Distal Ejecta
Dykes
LB
Volume of Melt
Depth of Melting

References

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R R Shrock, C A Malott (1933) The Kentland area of disturbed Ordovician rocks in Northwestern Indiana, The Journal of Geology 41(4), p. 337-370, url

R R Shrock (1937) Stratigraphy and structure of the area of disturbed Ordovician rocks near Kentland, Indiana, The American Midland Naturalist 18(4), p. 471-531, url

R S Dietz (1947) Meteorite impact suggested by the orientation of shatter-cones at the Kentland, Indiana, Disturbance, Science 105(2715), p. 42-43, American Association for the Advancement of Science, Washington, DC, url

R S Dietz (1947) Meteorite impact suggested by the orientation of shatter-cones at the Kentland, Indiana, disturbance, Science (Washington) 105, p. 43-44, url

A J Cohen, T E Bunch, A M Reid (1961) Coesite discoveries establish cryptovolcanics as fossil meterorite craters, Science 134(3490), p. 1624-1625, url

A J Cohen, A M Reid, T E Bunch (1962) Central uplifts of terrestrial and lunar craters: (Part) 1, Kentland and Serpent mound structures, Journal of Geophysical Research 67(4), p. 1632-1633, American Geophysical Union, Washington, DC

R C Gutschick (1972) Geology of the Kentland structural anomaly, Northwestern Indiana, Meteoritical Society, url

R C Gutschick (1976) Geology of the Kentland structural anomaly, Northwestern Indiana, Geological Society of America Annual Meeting, p. 1-59, url

R T Laney, W R V Schmus (1978) The Kentland impact site: A structural study of a partially dissected central uplift, Eos, Transactions, American Geophysical Union 59(4), p. 223, American Geophysical Union, Washington, DC, url

R T Laney, W R V Schmus (1978) A structural study of the Kentland, Indiana impact site, 9th Lunar and Planetary Science Conference, p. 2609-2632, url

R C Gutschick (1982) Geology of the Kentland structural anomaly, Northwestern Indiana - Update, Study for Earth Science Students: Field Guide, p. 1-38

R C Gutschick (1983) Geology of the Kentland Dome structurally complex anomaly, Northwestern Indiana, Field trips in midwestern geology, p. 105-138

G L Pavlis, K A Meyerholtz (1986) Refraction fan shot geotomography of the Kentland, Indiana, impact structure, Eos, Transactions, American Geophysical Union 67(44), p. 1102, American Geophysical Union, Washington, DC

M Jackson, R V D Voo (1986) A Paleomagnetic estimate of the age and thermal history of the Kentland, Indiana cryptoexplosion structure, Journal of Geology 94, p. 713-723, url

J F McHone, R S Dietz, W V Peredery, B O Dressler, V L Sharpton (1992) Sudbury breccia and suevite as glacial indicators transported 800 km to Kentland astrobleme, Indiana, LPI Contribution 790, p. 51, Lunar and Planetary Institute, Houston, TX, url

C Koeberl, V L Sharpton, T V V King, I Ridley (1993) Geochemical study of rocks from the Kentland, Indiana, impact structure: Progress report, Meteoritics 28(3), p. 382, Arizona State University, Center for Meteorite Studies, Tempe, AZ, url

C Koeberl, V L Sharpton (1993) Geochemical study of rocks from the Kentland, Indiana, impact structure: Progress report, Meteoritics 28, url

M N III Nasser, R C Howe (1995) Bedrock paleotemperature study of the Kentland impact site Kentland, Indiana, Proceedings of the Indiana Academy of Science 104(3-4), p. 201-211, url

M S Bell, V L Sharpton (1996) High-pressure shock effects in silica in St. Peter Sandstone from the Kentland Impact Structure, Indiana, USA, Meteoritics & Planetary Science 31, p. A13-A13, url

M G Bjørnerud (1998) Superimposed deformation in seconds: Breccias from the impact structure at Kentland, Indiana (USA), Tectonophysics 290(3-4), p. 259-269, url

L W D Bridges (2000) End-Cretaceous super-plume explosive events in North America caused by an expanding Earth, International Geological Congress, Abstracts = Congres Geologique International, Resumes 31, p. 0-unpaginated, [International Geological Congress], [location varies]

J B Burt, M C Pope (2001) Shock-induced effects of calcite crystals within the Kaibab Limestone at Meteor Crater, Arizona, Abstracts with Programs - Geological Society of America 33(6), p. 383, Geological Society of America (GSA), Boulder, CO, url

J Li, K J V Vliet, T Zhu, S Yip, S Suresh (2002) Atomistic mechanisms governing elastic limit and incipient plasticity in crystals, Nature 418(6895), p. 307-310, url, doi:10.1038/nature00865

J C Weber, C Poulos, R A Donelick, M C Pope, N Heller (2005) The Kentland impact crater, Indiana (USA): An apatite fission-track age determination attempt, Impact Tectonics, p. 447-466, url, doi:10.1007/3-540-27548-7_18

H Brusnahan, J Weber, R Reynolds (2007) Shock-metamorphic effects in lattice structure of sphalerite (ZnS) from polymict impact breccia dikes, Kentland Crater, Indiana, Abstracts with Programs - Geological Society of America 39(6), p. 373, Geological Society of America (GSA), Boulder, CO, url

H Brusnahan, J Weber, R Reynolds (2008) Shock-metamorphic effects in lattice structure of sphalerite (ZnS) from impact breccia in the Kentland Crater, Indiana, Michigan Academician 38(4), p. 58, Michigan Academy of Science, Arts and Letters, Ann Arbor, MI, url

J R Morrow, J C Weber (2009) Comparison of low-pressure shock-metamorphic effects in quartz from Barringer Crater, Arizona, and Kentland Dome, Indiana, 40th Lunar and Planetary Science Conference, pdf

M Schmieder, E Buchner (2011) Impact-related deformation features in Cherts from terrestrial impact structures, 42nd Lunar and Planetary Science Conference, url

J C Weber (2013) Impact geology: Central uplift, Kentland impact structure, Newton County Stone (Kentland) Quarry, Indiana, USA, GSA Field Guides 31, p. 1-7, Geological Society of America, url, doi:10.1130/2013.0031(01)

T Henderson, K A Milam (2015) XRD analyses of Silurian dolostones from the central uplift of the Kentland impact structure, Newton County, Indiana, USA, 46th Lunar and Planetary Science Conference, pdf

A J Cavosie, J Weber (2019) Micro-riedel shear zones as shear sense indicators in shocked zircon from sandstone in the central uplift of the Kentland impact structure, Indiana, USA, Large Meteorite Impacts VI(2136), url

C Hamilton (2019) A paleomagnetic and diagenetic study of the Kentland impact crater, url

E Flamini, A Coletta, M L Battagliere, M Virelli (2019) Kentland, USA, Encyclopedic Atlas of Terrestrial Impact Craters, p. 535-537, Springer International Publishing, url, doi:10.1007/978-3-030-05451-9_149