2000 Ma large mafic magmatic events

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164 Woodward event

Location: Australia (Halls Creek-King Leopold mobile belts)

Age: 2.0 Ga

Rating: B (4sd)

DIKES: Woodward (ca. 2000 Ma) Dow and Gemuts, 1969[469] (p.238 in Geological Survey of Western Australia, 1990[164]).

SILLS: Woodward sills (ca. 2000 Ma) Dow and Gemuts, 1969[469] (p.238 in Geological Survey of Western Australia, 1990[164]).

COMMENT: Wombarella quartz gabbro may also belong to this event Parker et al., 1987[216].


165 Niquelândia Lower Layered Series event

Location: C. Brazil (Goiás massif, Central Brazil Shield)

Age: ca. 2.0 Ga

Rating: C (8)

LAYERED INTRUSION: Barro Alto intrusion; Niquelândia intrusion, & Cana-Brava intrusion.

COMMENT: Lower Layered Series portion of tectonically fragmented, rift-related intrusion (or intrusions), Barro Alto, Niquelândia and Cana-Brava, extending for 350 km Ferreira Filho, 1998[368] Ferreira Filho and Pimentel, 2000[369] Ferreira-Filho et al., 1992[370] Suita et al., 1994[366]. Emplacement age (ca. 2.0 Ga) is still poorly defined owing to metamorphic resetting of isotopic systems Ferreira Filho, 1998[368]: Barro Alto (Uz 1730-1720 Ma Suita et al., 1994[366]) & Niquelândia (Uz 1560-1600 Ma Ferreira-Filho et al., 1994[367]). According to a recent interpretation, Lower Layered Series (LS) is ca. 2.0 Ga, while the Upper Layered Series (US) is 1.35 Ga and the LS and US were subsequently tectonically juxtaposed Ferreira Filho and Pimentel, 2000[369] Pimentel et al. 2000[370a]. See also event 117.


166 Kennedy continental flood basalt(C) event

Location: W. USA (Wyoming province)

Size: 60,000 sq. km.

Age: 2.01 Ga

Rating: B (5 & 7d)

DIKES: Kennedy [Cherry Creek], NE-ENE trending, U 2010±10 Ma Cox et al., 1995[470]) Cox et al., 2000[471] Snyder et al., 1989[472] Summers et al., 1995[473].

DIKE-LIKE LAYERED INTRUSIONS: layered intrusion: funnel-dike type (ca. 2000 Ma) Summers et al., 1995[473] Snyder, 1984[474] Tony Ridge, Long Canyon, Cherry Creek, & John Ballard.


167 Lac de Gras continental flood basalt(C) event LeCheminant et al., 1996[220]

Location: N. Canada (Slave province)

Size: 30,000 sq. km.

Age: 2.030-2.023 Ga

Rating: B (5)

DIKES: Lac de Gras, N-NNE trending, (U 2030-2023 Ma LeCheminant and van Breemen, 1994[475]) LeCheminant, 1994[476].

INTRUSION: Booth River mafic-ultramafic-felsic intrusive complex, Uz 2023+4/-2 Ma LeCheminant, 1994[476] Roscoe et al., 1987[477].


168 Hearne continental flood basalt(C) event

Location: Canada (Slave province)

Age: 2.04 Ga

Rating: B (5)

DIKES: Hearne, NE-ENE trending, (U 2037+3/-2 Ma Pehrsson et al., 1993[478]) Henderson, 1985[479].

COMMENT: Dated site is distant from main swarm, and correlation is uncertain.


169 Povungnituk Group continental flood basalt(C) events St-Onge et al., 1997[444]

Location: NE. Canada (Cape Smith belt)

Size: >7000 sq. km.

Age: 2.04-1.96 Ga

Rating: B (4vs)

VOLCANIC ROCKS: Povungnituk Group flood basalts St-Onge et al., 1997[444]: rhyolite in upper Povungnituk, Uz 1959±3 Ma Parrish, 1989[445].

SILLS: Korak sills (Uz 2038+4/-2 Ma Machado et al., 1993[446]).

SILL OR FLOW: (U ca. 1970 Ma in lower Povungnituk, S. Pehrsson, 2000, personal communication).

OTHER INTRUSION: granodiorite intruded into Povungituk Uz 1991±2 Machado et al., 1993[446].

COMMENT: Probably represents two events: at 2040 Ma and ca. 1960 (-1990?) Ma. Preserved in thrust package; are these sills related to Iglusuataliksuak dikes (NW trending) of Nain Province, dated at Ub ca. 2045 Ma Hamilton et al., 1998[480]?


170 Kangâmuit continental flood basalt(C) event

Location: W. & E. Greenland (Greenland Shield)

Size: 22,000 sq. km.

Age: 2.04 Ga

Rating: B (5)

DIKES: Kangâmuit, NE trending (Uz 2036±5 Ma, Uz 2046±8 Ma, U 2048±17 Ma Nutman et al., 1999[481]).


171 Otanmaki event

Location: C. Finland (Fennoscandian Shield)

Age: 2.04 Ga

Rating: C (possibly 9i)

SILL-LIKE LAYERED INTRUSION: Otanmaki layered mafic complex, 2040 Ma Papunen, 1995[482], Keivitsa layered complex Papunen, 1995[482].


172 Caraiba-Jacurici River Valley event

Location: Brazil (São Francisco Craton)

Age: 2.06 Ga

Rating: C (possibly 9i)

INTRUSIONS: Caraiba complex (numerous small bodies along Curaca Valley), ? NNE trending belt of mafic-ultramafic intrusions (Caraiba melanorite Uz 2051 Ma Oliveira, 1998[483])Wirth et al., 1990[418], Jacurici River Valley complexes (tens of bodies are distributed along a N-S zone that is ~70 km long; includes Medrado-Ipueira sill Wirth et al., 1990[418]) (Medrado gabbro Uz 2059 Ma Oliveira, 1998[483]).

COMMENT: Considered by Oliveira, 1998[483] to belong to Transamazonian, 2.0 Ga collisional event.


173 Bushveld continental flood basalt(C) event

Location: South Africa, Botswana (Kaapvaal Craton)

Size: 65,000 sq. km. & up to 9 km thick (for Bushveld intrusion) + 13,000 sq. km. (for Molopo Farms complex)

Age: 2.06 Ga

Rating: A (1s)

VOLCANIC ROCKS: Dullstroom basalts Eales and Cawthorn, 1996[484].

DIKES: ? Rykoppies, E trending Uken and Watkeys, 1997[88].

SILL-LIKE LAYERED INTRUSIONS: Bushveld layered intrusion (Ut 2058.9± 0.8 Ma Buick et al., 2000[484a]), (Ub ca. 2060 Ma, M. Hamilton, 2001, personal communication), (R 2061±27 Ma Walraven et al., 1990[485]) Eales and Cawthorn, 1996[484] Sharpe et al., 1981[486] Hatton, 1995[487]; Molopo Farms layered intrusion, R 2044± 24, Reichhardt, 1994[488].

LAYERED INTRUSION: Uitkomst intrusion de Waal and Gauert, 1997[489].

COMMENT: Correlated felsic Rooiberg Group U 2061±2 Ma Walraven et al., 1990[485].


174 Fort Frances continental flood basalt(C) event

Location: Canada, USA (Superior province)

Size: 75,000 sq. km.

Age: 2.075 Ga

Rating: B (5)

VOLCANIC ROCKS: Mille Lacs group rift volcanic rocks (p. 625 in Southwick and Day, 1983[489a]).

DIKES: Fort Frances (Kenora-Kabetogama), NW-NNW trending (Ubz 2076+5/-4 Ma Buchan et al., 1996[490]) (Ubz 2077+4/-3 Ma Wirth et al., 1995[491]) Halls, 1986[492] Wirth and Vervoort, 1995[493] Schmitz et al., 1995[494].

COMMENT: Marathon reversed dikes may belong to this swarm.


175 Cauchon continental flood basalt(C) event(s)

Location: Canada (nw Superior province, Canadian Shield)

Size: 3000 sq. km.

Age: 2.09-2.07 Ga

Rating: C (possibly 8)

DIKES: Cauchon (Molson), ENE trending Ubz 2091±2 Ma Halls and Heaman, 2000[433], NE trending, Uz 2072±3 Ma Heaman and Corkery, 1996[495] Halls and Heaman, 2000[433].

COMMENT: Probably related to continental breakup.


176 Snowy Pass event

Location: USA (Wyoming Block)

Size: >1000 sq. km.

Age: 2.101-2.083 Ga

Rating: C (possibly 8)

DIKES: gabbroic unit in Snowy Pass Supergroup in the Sierra Madre, (Uz 2092±9 Ma Premo and van Schmus, 1989[496]) Houston and Graff, 1995[497].

SILLS: gabbroic unit in Snowy Pass Supergroup in the Sierra Madre, (Uz 2092±9 Ma Premo and van Schmus, 1989[496]) Houston and Graff, 1995[497].

STOCKS: gabbroic unit in Snowy Pass Supergroup in the Sierra Madre, (Uz 2092±9 Ma Premo and van Schmus, 1989[496]) Houston and Graff, 1995[497].

COMMENT: "Abundant mafic sills, dikes and stock, some several hundred meters wide, intrude sedimentary rocks north of the Cheyenne Belt. Most are tholeiitic." They are also metamorphosed up to amphibolite grade Premo and van Schmus, 1989[496] Houston and Graff, 1995[497]. Model linking Snowy Pass intrusions to a Wyoming Craton breakup event is discussed in Roscoe and Card, 1993[498].


177 Paramaca Series event

Location: French Guiana (Guiana Shield)

Age: 2.11 Ga

Rating: C (possibly 7)

VOLCANIC ROCKS: Paramaca Series (includes ultramafic lavas) (S 2110±90 Ma Gruau et al., 1985[499]).

COMMENT: Linked with Marowijne Group (Sirinam) & Barama-Mazaruni Supergroup (Guyana) Choudhuri, 1980[500] Gruau et al., 1985[499].


178 Karelian continental flood basalt(C) event(s)

Location: Finland, Russia (Fennoscandian Shield)

Size: 210,000 sq. km.

Age: 2.11 Ga

Rating: B (5)

VOLCANIC ROCKS: Tohmajärvi; Oravaara (North Karelia schist belt) (U 2105±15 Huhma, 1986[501],Jouttiaapa (Peräpohja schist belt) (S 2090±79 Ma Huhma et al., 1990[502]).

DIKES: North Karelia, SE trending, (U 2112, 2113±4, 2105 Ma Vuollo et al., 1995[461]); Perä Pohja, SE trending, U 2114±14 Ma Vuollo et al., 1995[461]; Kuusamo, ENE-E trending, U 2078±8 Ma Vuollo et al., 1995[461].


179 Griffin (Hurwitz) event

Location: Canada (Hearne province, Canadian Shield)

Size: 80,000 sq. km.

Age: 2.111 Ga

Rating: B (4s)

VOLCANIC ROCKS: Happotiyik Member of Ameto formation Sandeman et al., 2000[504].

SILLS: Griffing (Hurwitz) Ub 2111.2±0.6 Ma Heaman and LeCheminant, 1993[326] Aspler et al., 1994[503].

COMMENT: The name Griffin, proposed by L. Aspler, 2001, personal communication.


180 Marathon-reversed continental flood basalt(C) event

Location: S. Canada (Superior Province)

Size: 60,000 sq. km. (for combined events 180 & 181)

Age: ca. 2.1 Ga

Rating: B (5)

DIKES: Marathon-reversed (paleomagnetic polarity), N trending Buchan et al., 1996[490].

COMMENT: May be related to the Fort Frances dikes on the basis of paleomagnetic direction and geochemistry Buchan et al., 1996[490]. Intermixed dikes of normal paleomagnetic polarity are presented in event 181.


181 Marathon-normal continental flood basalt(C) event

Location: S. Canada (Superior Province)

Size: 60,000 sq. km. (for combined events 180 & 181)

Age: 2.12 Ga

Rating: B (5)

DIKES: Marathon-normal (paleomagnetic polarity), N trending (U 2121+17/-7 Ma Buchan et al., 1996[490]).

COMMENT: Intermixed dikes of reversed paleomagnetic polarity are presented in event 180.


182 Labrador Coast event

Location: E. Canada (Nain province)

Age: 2.12 Ga

Rating: B (5)

DIKES: Tikkigatsiagak, NE trending, U 2121±1.5 Ma Hamilton et al., 1998[480].

COMMENT: May correlate with Napaktok and Domes dikes Hamilton et al., 1998[480]. Only broadly correlative with NE trending Avayalik dikes (U ca. 2139 Ma) Hamilton et al., 1998[480].


183 Mahbubnagar event

Location: S. India (eastern Dharwar Craton)

Size: ? 60,000 sq. km.

Age: 2.24-2.11 Ga

Rating: B (5)

VOLCANIC ROCKS: ?Cuddapah volcanic rocks Pandey et al., 1997[505].

DIKES: ?Mahbubnagar, NW trending, S 2173±64 Ma Pandey et al., 1997[505] Murthy, 1987[421].


184 Biscotasing continental flood basalt(C) event

Location: Canada (Superior Province)

Size: 180,000 sq. km. (for Biscotasing dikes); 30,000 sq. km. (for volcanic rocks)

Age: 2.17 Ga

Rating: B (5)

VOLCANIC ROCKS: Findlay et al., 1995[438]: Le Fer (Bacchus); rhyolite in Mistamisk formation is U 2142+4/-2 Ma (B. Dressler & T. Krogh cited in Clark, 1984[506].

DIKES: Biscotasing, NE trending, U 2167±2 Ma Buchan et al., 1993[507] Buchan et al., 1994[508]; Payne River, SE trending, 2175-1790 Ma Fahrig et al., 1986[509] Fahrig and West, 1986[510], (U ca. 2170-2160 Ma, S. Pehrsson, 2000, personal communcation).

SILLS: Cramolet Lake (U 2169±4 Ma Rohon et al., 1993[440]).

COMMENT: Volcanic rocks & sills collectively grouped as New Quebec orogen cycle 1 magmatism Findlay et al., 1995[438]. Payne River dikes, Biscotasing dikes & New Quebec cycle-1 magmatism linked by S. Pehrsson (1999, personal communication).


185 Dogrib continental flood basalt(C) event

Location: Canada (Slave province)

Size: 11,000 sq. km.

Age: 2.19 Ga

Rating: C (possibly 5)

DIKES: Dogrib, ENE trending, U 2190 Ma LeCheminant et al., 1997[511] McGlynn and Irving, 1975[512].


186 Tulemalu continental flood basalt(C) event

Location: Canada (W. Churchill province)

Size: 15,000 sq. km.

Age: 2.19 Ga

Rating: B (5)

DIKES: Tulemalu, E trending, Ub 2190 Ma LeCheminant et al., 1997[511] Sandeman et al., 2000[504] Fahrig et al., 1984[513]; MacQuoid (U ca. 2200 Ma Tella et al., 1997[514] Sandeman et al., 2000[504].


187 Birimian (O & C) events Abouchami et al., 1990[515]

Location: West Africa (West African Craton)

Size: 2,000,000 sq. km.

Age: 2.19 & 2.10 Ga

Rating: B (4v)

VOLCANIC ROCKS: Abouchami et al., 1990[515] Attoh and Ekwueme, 1997[516] (p. 332-333 in Goodwin, 1991[180]) Tsalabya El Khadra (Mauritania) Abouchami et al., 1990[515]; Yaouré, Toumodi, and Haute-Comoé (Ivory Coast) Abouchami et al., 1990[515]; Bouroum series (Burkina Faso) Abouchami et al., 1990[515]; Liptako (Niger) Abouchami et al., 1990[515]; Mako (Senegal) Abouchami et al., 1990[515]; Sefwi (Ghana) Abouchami et al., 1990[515]; Nangodi (ne. Ghana) Attoh and Ekwueme, 1997[516]; Dixcove-Konongo (Ghana) Attoh and Ekwueme, 1997[516]. Rhyolite lava associated with tholeiitic basalts of Sefwi belt gives an age of Uz 2189±1 Ma Hirdes and Davis, 1998[517]. Rhyodacite from Birimian volcanic belt in southern Mali yields Uz 2098±5 Ma Liegois et al., 1991[518].

COMMENT: Two age groups of volcanism and coeval plutonism can be distinguished Hirdes et al., 1996[519]: Eastern Subprovince (2185-2150 Ma) includes units in Ghana, eastern Côte d'Ivoire, & probably many parts of Burkino Faso. The Western Subprovince (ca. 2105 Ma) includes units in central Côte d'Ivoire, western Mali, and probably Guinea. It is suggested that "Birimian" be used for 2185-2150 Ma event and "Bandamian" be used for 2105 Ma event Hirdes et al., 1996[519]. Plume origin favored by Abouchami et al., 1990[515], but collisional origin advocated by Attoh and Ekwueme, 1997[516].


188 Diapaga event

Location: Niger, Burkina Faso

Size: 60,000 sq. km.

Age: = 2.1 Ga

Rating: B (5)

DIKES: Diapaga, N trending, =2100 Ma Ernst et al., 1996[117] Machens, 1966[520] Bérard and Tanguay, 1972[521].

COMMENT: Perhaps part of Birimian event.


189 Ayorou event

Location: Niger, Burkina Faso

Size: 135,000 sq. km.

Age: = 2.1 Ga

Rating: B (5)

DIKES: Ayorou, ESE trending, =2100 Ma Ernst et al., 1996[117] Machens, 1966[520] Bérard and Tanguay, 1972[521].

COMMENT: Perhaps part of Birimian event.


190 Deweras continental flood basalt(C) event

Location: Zimbabwe (NW. & W. Zimbabwe craton)

Size: 36,000 sq. km. (dikes), up to 10 km thick (volcanic rocks)

Age: 2.15 Ga

Rating: B (5, 4v)

VOLCANIC ROCKS: Deweras ca. 2170 Ma (p. 324 in Goodwin, 1991[180]); <2060±100 Ma Eriksson et al., 1999[522].

DIKES: Plumtree NE-NNE arcuate swarm (ca. 2150 Ma) Wilson et al., 1987[256].

COMMENT: Sediments and basalts deposited in a rift or intracratonic basin (p. 323 in Goodwin, 1991[180]). Plume origin advocated in Eriksson et al., 1999[522].


191 Ungava continental flood basalt(C) event

Location: NE. Canada (Superior province)

Plume head center: 58 N, 66 W

Size: 170,000 sq. km.

Age: 2.22-2.21 Ga

Rating: A (3)

DIKES: Ungava WNW-SW fanning swarm Buchan et al., 1998[463]: include subswarms Klotz (Uz 2210±1 Ma), Maguire (U ca. 2230 Ma) and Senneterre U 2216+8/-4 Ma).

SILLS: Nipissing, U 2217±4 Ma Lightfoot, 1995[523] Buchan et al., 1998[463].


192 MacKay continental flood basalt(C) event

Location: Canada (Slave province)

Size: length of swarm is 200 km

Age: 2.21 Ga

Rating: C (possibly 5)

DIKES: MacKay (& X dikes), ENE-E trending, (U ca. 2210 Ma LeCheminant and van Breemen, 1994[475]) LeCheminant, 1994[476] McGlynn and Irving, 1975[512].


193 BN-1 event

Location: W. Greenland (Greenland Shield)

Size: 54,000 sq. km.

Age: 2.224-2.204 Ga

Rating: B (5)

DIKES: BN-1 (boninitic), NNW-NNE trending, (U 2214±10 Ma Nutman et al., 1995[524]) Hall and Hughes, 1987[525] Bridgwater et al., 1995[526].


194 Cheela Springs continental flood basalt(C) event

Location: NW. Australia (Hamersley province)

Age: 2.21 Ga

Rating: C (possibly 4v)

VOLCANIC ROCKS: Cheela Springs (Uz 2209±15 Martin et al., 1998[527]) Martin et al., 2000[528].


195 Koli continental flood basalt(C) event

Location: Finland (Fennoscandian Shield)

Size: 130,000 sq. km.

Age: 2.21 Ga

Rating: B (4s)

SILLS: Karjalite diabase sills Vuollo et al., 1995[461]: include Perä Pohja (U 2200 Ma), Lapland (U 2220±11 Ma), Kuusamo (U 2206±9 Ma), Kuhmo (2172 Ma), Koli (>2170 Ma).


196 Ongeluk-Hekpoort continental flood basalt(C) event

Location: South Africa, Botswana (Kaapvaal Craton)

Size: 200,000 sq. km.

Age: 2.22 Ga

Rating: B (4v)

VOLCANIC ROCKS: Ongeluk basaltic andesite lavas, P 2222±13 Ma Cornell et al., 1996[529], (p. 315 in Goodwin, 1991[180]); Hekpoort basaltic andesite lavas Cornell et al., 1996[529]; Ditlhojana volcanic rocks Cornell et al., 1996[529]; Pretoria Gp 2224±21 Ma (p. 316-317 in Goodwin, 1991[180]).

COMMENT: Plume origin advocated in Eriksson et al., 1999[522].


197 Malley continental flood basalt(C) event

Location: Canada (Slave province)

Size: 25,000 sq. km.

Age: 2.23 Ga

Rating: B (5)

DIKES: Malley, NE trending, (U ca. 2230 Ma LeCheminant and van Breemen, 1994[475]) LeCheminant, 1994[476].


198 Vestfold Hills-2 continental flood basalt(C) event

Location: Antarctica (Vestfold Block)

Size: 250 sq. km.; much larger if correlated with dikes in Napier complex ca. 1000 km away

Age: 2.24 Ga

Rating: C (possibly 5)

DIKES: Vestfold Hills-2, NNE-NW trending Hoek and Seitz, 1995[530] Lanyon et al., 1993[531], (Uz 2241±4 Ma, Uz 2238±7 Ma, Lanyon et al., 1993[531]).

COMMENT: Size of swarm limited by the small size of the basement outcrop. However, compositionally similar high-Mg dikes in the Napier Complex (~1000 km away) may be linked Lanyon et al., 1993[531].


199 Dalma-Dhanjori event

Location: E. India (Singhbhum Craton)

Size: up to 10 km of lavas

Age: 2.4-2.3 Ga

Rating: B (4v)

VOLCANIC ROCKS: (p. 338-339 in Goodwin, 1991[180]): Dalma (includes ultramafic lavas) Gupta et al., 1980[533] Gupta et al., 1982[534]; Dhanjori (includes ultramafic volcanic rocks) Gupta et al., 1985[535]; Ongarbira Gupta et al., 1981[536] Blackburn and Srivastava, 1994[532]; Jagannathpur; Dhanjori-Simlipal; Dalmar; Malangtoli; Dhalbhum formation Eriksson et al., 1999[522].

INTRUSIONS: widespread mafic-ultramafic intrusions (p. 339 in Goodwin, 1991[180]).

COMMENT: Mantle upwelling (plume) model proposed by Gupta et al., 1980[533] and supported by Eriksson et al., 1999[522]. Plume & alternative models discussed in Blackburn and Srivastava, 1994[532]. Arguments against an Archean age for the Ongarbira volcanic rocks are presented in Blackburn and Srivastava, 1994[532].


200 Cateté continental flood basalt(C) event

Location: Brazil, Pará State

Size: 500 km long

Age: 2.4 Ga

Rating: C (possibly 9i)

LAYERED INTRUSIONS: Onça, Puma, Jacaré, Jacerezinho, Igarapé Carapana, 2378±55 Ma Macambira, 1997[537].

COMMENT: Part of a 500-km-long E trending suite of layered complexes intrusive into the Xingú Complex (an Archean granite-gneiss terrane).


201 Vestfold Hills-1 and Napier Complex-1 continental flood basalt(C) event(s)

Location: Antarctica (Vestfold Block & Napier Complex)

Size: 1200 km long (if one swarm).

Age: 2.4 Ga

Rating: C (possibly 5)

DIKES: Vestfold Hills-1, E trending, R ca. 2400 Ma Hoek and Seitz, 1995[530] Lanyon et al., 1993[531] Ernst et al., 1996[117]; Napier Complex-1, SE trending, R ca. 2400 Ma Sheraton et al., 1987[303] Ernst et al., 1996[117].


202 Widgiemooltha continental flood basalt(C) event

Location: W. Australia (Yilgarn Craton)

Size: 640,000 sq. km. Ernst et al., 1996[117]

Age: 2.42-2.41 Ga

Rating: B (5)

DIKES: Widgiemooltha, E-ENE trending, (U 2410.6+2.1/-1.6; U 2410.2+2.3/-2.1 Ma Doehler and Heaman, 1998[538]) (Ub 2418±3 Ma Nemchin and Pidgeon, 1998[539]) Geological Survey of Western Australia, 1990[164]. Includes Binneringie dike & Jimberlana intrusion.


203 Kaminak continental flood basalt(C) event

Location: Canada (W. Churchill province, S. Hearne)

Size: 18,000 sq. km.

Age: 2.45 Ga

Rating: B (5)

VOLCANIC ROCKS: Spi Group Beavon, 1976[540] Sandeman et al., 2000[504].

DIKES: Kaminak, N-NW trending, Sandeman et al., 2000[504] Christie et al., 1975[541] Fahrig et al., 1984[513], (U ca. 2450 Ma Heaman, 1994[542]).


204 Mistassini continental flood basalt(C) event

Location: Canada (Superior province)

Plume head center: 50 N, 71 W

Size: 100,000 sq. km.

Age: 2.47 Ga

Rating: A (3)

DIKES: Mistassini (NW-NNW fanning swarm) (U ca. 2470 Ma Heaman, 1994[542]) Fahrig et al., 1986[509].

COMMENT: Includes some dikes with composition of basaltic komatiites.


205 Woongarra continental flood basalt(C) event Barley et al., 1997[543]

Location: Western Australia (Hamersley basin)

Size: 40,000 sq. km.

Age: 2.452-2.446 Ga

Rating: B (4v)

VOLCANIC ROCKS: Weeli Wolli diabase sills and basalt flows (age of interbedded felsic tuff Uz 2449±3 Ma) Barley et al., 1997[543].

SILLS: Weeli Wolli diabase sills and basalt flows (age of interbedded felsic tuff Uz 2449±3 Ma) Barley et al., 1997[543].

FELSIC VOLCANIC ROCKS: Woongarra rhyolites Uz 2449±3 Ma Barley et al., 1997[543].

COMMENT: Backarc setting suggested by Barley et al., 1997[543].


206 Matachewan continental flood basalt(C) event(s) Ernst and Buchan, 1997a[5] Heaman, 1997[544] Halls and Zhang, 1998[544a]

Location: Canada (Superior province)

Plume head center: 45 N, 81 W

Size: 360,000 sq. km.

Age: 2.49-2.44 Ga

Rating: A (3)

VOLCANIC ROCKS: Elliot Lake Group Copper Cliff rhyolites (Uz 2450+25/-10 Ma Krogh et al., 1984[545]; Thessalon volcanic rocks.

DIKES: Matachewan [Hearst] NW-N fanning swarm (U 2473+16/-9 & 2446±3 Ma Heaman, 1997[544]) Halls and Zhang, 1998[544a] Halls, 1991[544b] Bates and Halls, 1991[546] West and Ernst, 1991[547] Condie et al., 1987[548] Nelson et al., 1990[549] Phinney and Halls, 2001[549a]; Streich feeder dike and related dikes Vogel et al., 1999[550] Vogel et al., 1998a[551].

SILL-LIKE LAYERED INTRUSIONS: East Bull Lake Suite Vogel et al., 1999[550] includes: Savage Bull complex Chubb et al., 1994[552] gently folded layered sill complex, includes: East Bull Lake intrusion U 2480+10/-5 Ma, Agnew intrusion [Shakespeare-Dunlop] U 2491±5 Ma Krogh et al., 1984[545] and Streich feeder dike). River Valley U 2475±2 Ma Heaman, 1995[553]; Falconbridge Twp. (U 2441±3 Ma) Prevec, 1993[554] Vogel et al., 1998a[551] Vogel et al., 1998b[555].

INTRUSION: Murray granite pluton, 2477±9 Krogh et al., 1996[556].

COMMENT: Vogel et al. 1998 Vogel et al., 1999[550] used "East Bull Lake Suite" for all the intrusions, including River Valley pluton. However, Chubb et al. 1994 Chubb et al., 1994[552] used Savage Bull complex to encompass the East Bull Lake, Agnew intrusion, and Streich feeder dike.


207 Northern Baltica-1 continental flood basalt(C) events

Location: Finland, Norway, W. Russia (Fennoscandian Shield)

Size: 500,000 sq. km.

Age: 2.505-2.490 Ga & 2.445-2.436 Ga

Rating: A (1v)

VOLCANIC ROCKS: volcanic belts: lower Pechenga, Varzuga, Pana-Kuolajarvi, Vetreny (Uz 2437±3 Ma Puchtel et al., 1997a[557], Salla [Lapponian] Sharkov and Smolkin, 1998[462] Amelin et al., 1995[558] Smolkin, 1997[559] Manninen, 1991[560] (p. 241-243 in Goodwin, 1991[180]).

DIKES: Pääjärvi, SE trending, U ca. 2440 Ma Vuollo et al., 1995[461] Perttunen, 1987[561]; Viianki, NE trending, (U ca. 2440 Ma Vuollo, 1994[562]).

MAINLY SILL-LIKE LAYERED INTRUSIONS: 2445-2433 Ma layered intrusions Smolkin, 1997[559] Sharkov and Smolkin, 1998[462]: Burakovsky (Burakovka) (Uz 2449±2 Ma, Olanga (Oulanka), Koillismaa complex (S 2436±5 Ma), Näränkävaara (S 2440±16 Ma), Portimo, Narkaus, Penikat, Kemi, Tornio (Kukkola-Tornio), Koitelainen (U 2433±8 Ma) & Akanvaara, Imandra (U 2441±2 Ma), Pansky Tundra anorthosites (U 2449±2 Ma), Kivakka (U 2445±2, 2444±1 Ma), Mount Pyrshin (U 2452±7 Ma), Kolvitsa Tundra (U 2450±10 Ma), Main Ridge (U 2453±3 Ma), Lukkulaisvaara (U 2442±2 Ma), Tsipringa (U 2441±1 Ma), Drusite complex (U 2451±17 Ma).2505-2490 Ma layered Intrusions Smolkin, 1997[559] Sharkov and Smolkin, 1998[462] Pansky Tundra gabbro-pegmatite (U 2502±2, 2491±2 Ma), Fedorova Tundra, Fedorov-Pana, Monche (Monchegorsk) (U 2493±7 Ma), General'skaya Mountain (U 2505±2 Ma), Karikyavr, Zasteid, & Ondomozero intrusions.


208 Cobbold event

Location: NE. Australia (Georgtown inlier)

Age: ca. 2.5 Ga

Rating: C (possibly 9s)

VOLCANIC ROCKS: Dead Horse Black and McCulloch, 1984[563].

DIKES: Cobbold Withnall et al., 1980[564], S ca. 2490±70 Ma Black and McCulloch, 1984[563] Parker et al., 1987[216].

SILLS: Cobbold Withnall et al., 1980[564], S ca. 2490±70 Ma Black and McCulloch, 1984[563] Parker et al., 1987[216].

COMMENT: Metamorphosed to amphibolite grade Black and McCulloch, 1984[563].


209 Wolkberg-Buffalo Spring event

Location: South Africa (Transvaal basin)

Age: 2.7 - 2.2 Ga

Rating: C (possibly 9v)

VOLCANIC ROCKS: Wolkberg Group & Buffalo Springs (=Schmidtsdrif) (p. 314 in Goodwin, 1991[180]).

COMMENT: Stratigraphically between Ventersdorp (entries 219, 223, & 234) and Ongeluk (in event 196).


210 Tanzania-1 event(s)

Location: Tanzania

Size: 140,000 sq. km.

Age: 2.6-2.2 Ga

Rating: B (5)

DIKES: Tanzania-1 (Swarm 1), ENE trending, K 2600-2200 Ma Halls et al., 1987[239] Ernst et al., 1996[117].