“Impact Database” grew out of a brief reconnaissance of confirmed and proposed impact structures in Shell during 2004-2006. Its abbreviated version containing unconfirmed impact sites was published in June 2005 as the “Suspected Earth Impact Sites” (SEIS) database through the Impact Fields Studies Group website. SEIS was updated several times until the last edition in March 2008. In July 2009, the new “Impact Database v. 2009.1” replaced SEIS with much expanded content and graphic presentation. The database continues to evolve and updates will be published periodically.
The database currently contains all of the confirmed impact structures and most of the proposed ones. The goal is to eventually compile and evaluate information from original sources and to avoid referring to compilations of impact structures, which either do not indicate sources of information, are outdated, may have been of questionable quality to begin with and/or do not provide all the data collected here. This goal has been achieved for 55.8 % of the impact sites. Those include the sites that were classified confirmed in various databases despite the lack of evidence or were excluded from confirmed lists despite ample evidence for impact origin.
The database of impact related deposits (not only ejecta but also growing number of tsunamites and mass wasting deposits) is in an early stage of development and contains only a fraction of ejecta sites for well known impact events and strewn fields. However, it does contain a number of individual and lesser known proposed sites across geologic time.
Added all confirmed structures: Several structures commonly listed as confirmed (e.g. Earth Impact Database as of 13 April 2009, http://www.unb.ca/passc/ImpactDatabase) have been reclassified
Added probable impact structures: Ritland
Added suspected impact structures: unnamed (21.353, 9.145), Urengoy, Minch Basin, Hickman, Puget Sound, Wilkes Land 2, White Cliffs, MAPCIS, Panela
Added improbable and rejected structures: Arianna, unnamed (25.856, 0.582), Pawtuckaway, unnamed (44.258, 109.35), unnamed (42.209, 107.835), unnamed (18.388, 20.056), Pantasma, unnamed (56.21, -139.26)
General/notes updates: Silverpit, Elko, Panamint, Kanmare, Tabban, Al Umchaimin, Grendel, Praia Grande, Quetzalcoatl, Burckle, Joey, Judge, Kangaroo, Umm al Binni (Al'Amarah), Sakhalinka, Wilkes Land 1, Johnsonville, Sheeba merged with Shiva, Shiva, Gunnison, El-Baz, Merna, Uijongbu (Seoul), Kobrin, Magyarmecske, Merna
Downgraded to class 4 or 5: Köfels, Arkenu 1 and 2, Tarek (Gilf Kebir GKCF59), El-Mrayer
Added database of impact deposits.
23 January 2008
Added probable impact structures: Suavjärvi
Added suspected impact structures: Shaybah, Arkenu 1 and 2
Added improbable and rejected structures: La Fossa, Luobusa, Bender
General/notes updates: Potomskii, Tunguska, El Mirba, Al Madafi, Wasita, Eltanin, Kunya-Urgench, Sterlitamak
Downgraded to class 4 or 5: none
13 April 2007
Added probable impact structures: Victoria Island, Ishim, La Dulce, Kurai Basin, Suavjärvi
Added suspected impact structures: Black Rock, Tâterât, Congo Basin, Kalushskaja, Sakhalinka, Numbulwar, Rose River, Yarrawirrie, Cuvette Centrale, Meggyespuszta, San Martin, Shaybah, Arkenu 1 and 2
Added improbable and rejected structures: Gorski Kotar, Luobusa, Bender
General/notes updates: Loch Leven, Dakhleh (upgraded), Silverpit, Ramgarh, Tunguska, Mendorf, Willenhofen, Wipfelsfurt, Sausthal, Saal, Riga, Reitz Ring, Fohn, Arroyo Las Garzas, Herbert, Lennis, Aimorés, Azenak East, Azenak West, Santa Fe – Hyde Park (upgraded), Takamatsu, Fikes, Cowell, Sirente, Tunguska, Berdichev, Tverdovo, Aukstadvaris, Minsk, Idritsa, Ostashkov, Otnos, El Mirba, Al Madafi, Wasita, Eltanin, Kunya-Urgench, Sterlitamak
Downgraded to class 4 or 5: Gunnison (4), Nichols Knob (4), Big Yoeman (4), Blue Buck (4), Dyestone Mt. (4)
The indication of the burial (Y or N) was replaced by the thickness of rock overburden and present day water depth. The water depth is >0 m if the structure is completely hidden under water. A lake filling a structure does not count, as the rim and/or central peak of the structure are exposed.
Indication of target rocks, target water depth and projectile type – all presented assuming impact origin of the structures. Target types: W – water, M – metamorphic, I – igneous, S – sedimentary with indexes s – siliciclastic, c – carbonate, e – evaporite. The rock types tend to be presented in the order of decreasing volume in the target.
11 January, 2007
Added probable impact structures: Magyarmecske, Alz, Liberty, Faya
Added suspected impact structures: Luna, Nestiar, Madagascar 1, Madagascar 2, Madagascar 3, Madagascar 4, Madagascar 5,
Added rejected structures: Meteor Strike
General/notes updates: Laguna Guatavita, Carolina Bays, Gihan/Tarek (downgraded), Arkhys, Svetloyar/Svetlojar, Sredne-Uralskaya, Bangweulu (downgraded), Belinga, Bizeneuille (downgraded), Kogo (downgraded), Mékambo (downgraded), Minkébé (downgraded), Ntwentwe (downgraded), Mazoula, El Mouilah, Hardangervidda (downgraded), Pechenga, Lyksele (upgraded), Duolun, Tsenkher, Wilbarger, St. Magnus Bay, Wipfelsfurt, Lukanga, Lake Constance, Pfahldorf
Rejected (i.e., class 4 or 5): Richat, Semsiat, Foum Teguentour, Aflou, El-Baz, Bangui, St. Imier
Removed duplicated structures: one of the unnamed structures duplicating Wilbarger
2 October 2006
Removed duplicated structures: Mantta ( Keurusselkä), Sylvan (Ames), X-SAR 16 (Deep Bay)
Added probable impact structures: Johnsonville, Jackpine Creek, Tabban, Burckle, Kanmare
Added suspected impact structures: Omeonga, Gunnison, Las Praderas, Bajada del Diablo, Meseta del Canguel, Judge, Quetzalcoatl, Grendel, Kangaroo, Joey
Corrected coordinates: Quillagua, Gourma, Watterson Lake, Melavesi, Limgytynot
General/notes updates: Bohemia, Mt. Oikeyama, Dhala, São Miguel do Tapuio, Bushveld, Azuara, Rubielos de la Cérida, Carolina Bays, X-SAR 17, Silvergopen corrected to Silvergropen, Santa Fe - Hyde Park, Jeptha Knob, Hudson Bay, Sirente
Rejected: X-SAR 17
Continent field updated for several structures.
10 July 2006
In total 170 structures have been
updated. Among them many
changes applied to the whole database involve: