Impact Database

v. 2010.1

Introduction

History and current status

Data

Impact geology primer

How to contribute

Credits



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and to avoid referring to compilations of impact structures, which either do not indicate sources of information, are outdated, may have been of questionable quality to begin with and/or do not provide all the data collected here.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 58 % 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.

Archive of previous versions, including SEIS...

Previous updates...

Current updates:

16 May 2010



Class

Number of structures

Original work and data reviewed in detail / Compiled from various sources

0 - confirmed

175

57 / 118

1 - most probable

9

9 / 0

2 - probable

109

88 / 21

3 - suspected

476

264 / 212

4 - improbable

335

33 / 0

5 - rejected

94

70 / 24

Total

896

521 / 375



Notable structures/updates in bold

Big Basin – revised notes, coordinates, age, class 2-->5

unnamed (18.3913, -100.4011) – added structure, class 5

Unnamed -10.2127, -61.3802 – added structure, class 3

Unnamed 15.6528, 44.6978 – added structure, class 4

Muglad Basin – added structure, class 3

Unnamed -14.427595, 14.05912 – added structure, class 4

Unnamed 29.9412, -8.4242 – added structure, class 5

Unnamed -48.699301, -70.097498 – added structure, class 5

Unnamed -41.243441, -66.964804 – added structure, class 5

Unnamed 43.22824, 54.42441 – added structure, class 3

Unnamed 44.923, 52.367 – added structure, class 3

Unnamed 32.0203, 65.3599 – added structure, class 4

Abimily– added structure, class 4

unnamed (42.923, -71.558) – added structure, class 3

Kizyl Chilik – added structure, class 3

Murumbo – added structure, class 3

Semsiat – corrected latitude

Chicxulub II – added structure, class 3

Popigai II, III, IV – added structures, class 3

Obolon – notes/age updated

Morokweng – original notes written

Muskingum – corrected longitude from positive to negative

Merewether – corrected longitude from positive to negative

Lima – corrected continent

Kamensk – revised notes, coordinates, diameter, age

Gusev – revised notes, coordinates, diameter, age, 0-->1

Chicxulub – revised notes on age

Al Umchaimin – added reference

Puka – added structure, class 3

unnamed (34.879, 65.354) – added structure, class 4

unnamed (35.020, 65.085) – added structure, class 3

unnamed (-15.1523, 12.3660) – added structure, class 4

unnamed (23.0314, -3.5317) – added structure, class 5

unnamed (22.5140, -3.4026) – added structure, class 5

unnamed (24.0391, -5.8886) – added structure, class 5

unnamed (-13.540, 35.326) – added structure, class 5

unnamed (-13.759, 35.414) – added structure, class 5

unnamed (18.053, 33.500) – added structure, class 5

Zhongcangxiang– added structure, class 2

Woodbury – corrected longitude from positive to negative

Ahlshausen – added, class 4

Wedowee – added, class 3

Karelia – added, class 3

unnamed (22.9943, 12.6313) – added structure, class 3

Piccaninny – coordinates revised

Gosses Bluff – updated info on age and shock evidence

Gardnos – updated age after Jourdan et al. (2009)

Alvasjön – revised notes, coordinates, diameter

Mullsjön – revised notes, coordinates, diameter, age

Chesapeake Bay – added age review by Jourdan et al. (2009)

Boltysh – added age review by Jourdan et al. (2009)

Araquainha – updated age from Jourdan et al. (2009)

Jänisjärvi – age updated

unnamed (-23.0050, 127.8787) – added structure, class 3

Bloody Creek – added, confirmed

Granby – confirmed, original notes written

Lonar – projectile added

Carancas – added work of Kenkman et al. (2009)

Loch Leven – corrected longitude from positive to negative


Impactites, meteoritic debris:

Dust layers at Antarctic EPICA-Dome C and Dome Fuji – Added, class 0

12.9 ka (Firestone et al., 2007) – updated notes with recent work, class 3-->4



Previous updates:

10 October 2009

Class

Number of structures

Original work and data reviewed in detail / Compiled from various sources

0 - confirmed

175

53 / 122

1 - most probable

8

8 / 0

2 - probable

109

88 / 21

3 - suspected

459

247 / 212

4 - improbable

25

25 / 0

5 - rejected

83

59 / 24

Total

859

480 / 379



Santa Fe (class 2-->0)

Suavjärvi (class 2-->3)

Patom (Patomskii) (class 3-->5)

Gorski kotar (coordinates)

Transylvania_Henderson (reference)

Anefis (coordinates, notes)

Terhazza (coordinates, notes)

Black Rock (diameter, references)

Added: Seghaleh (class 3), unnamed (22.755, -6.638) (class 5)


1 July 2009

Class

Number of structures

Original work and data reviewed in detail / Compiled from various sources

0 - confirmed

174

52 / 122

1 - most probable

8

8 / 0

2 - probable

111

90 / 21

3 - suspected

458

246 / 212

4 - improbable

25

25 / 0

5 - rejected

81

57 / 24

Total

857

478 / 379



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

  • Põrguhaud and Sügavhaud (both at Ilumetsa), Liverpool, Matt Wilson – downgraded to “most probable”

  • Calvin, Crawford, Suavjärvi, Viewfield - downgraded to “probable”

  • Kuradihaud and Tondihaud (both at Ilumetsa) - added as “suspected”.

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
- new structures were added (some quite promising - see Tim McElvain's structures)
- duplicate structures unified
- coordinate accuracy and precision improved
- structures reclassified, mainly rejected
- detailed notes added

The changes applied to the whole database involve:
- reformatting the Notes so that each note includes a reference list and the master reference list is now eliminated.
- modification of the classification scheme - 1-confirmed, 2-probable, 3-proposed/possible, 4-improbable, 5-rejected