Poorly dated large mafic magmatic events
278 Diamond Springs event
Location: W. USA (Wind River Range, Wyoming Craton)
Age: Archean
Rating: C (possibly 7)
VOLCANIC ROCKS: Diamond Springs Formation (includes meta-ultramafic rocks) Wilks and Harper, 1997[687].
COMMENT: Ultramafic rocks have been variously interpreted as meta-komatiites and meta-cumulates (of an ophiolite) Wilks and Harper, 1997[687].
279 Araras event
Location: Brazil
Size: 80,000 sq. km.
Age: 1.5-0.9 Ga
Rating: B (5)
DIKES: Araras, SE trending, 1500-900 Ma, Teixeira, 1990[688] Ernst et al., 1996[117].
280 Tapajós event
Location: Brazil
Size: 35,000 sq. km.
Age: 1.6-0.9 Ga
Rating: B (5)
DIKES: Tapajós, NE trending, 1600-900 Ma, Teixeira, 1990[688] Ernst et al., 1996[117].
281 Cachorro event
Location: Brazil
Size: 60,000 sq. km.
Age: 1.6-0.9 Ga
Rating: B (5)
DIKES: Cachorro, ENE trending, 1600-900 Ma Teixeira, 1990[688] Ernst et al., 1996[117].
282 Jauru event
Location: WC. Brazil (S. Amazonian Craton)
Age: Early-Middle Proterozoic
Rating: C (possibly 7)
VOLCANIC ROCKS: Pinho et al., 1997[689] Jauru (includes ultramafic volcanic rocks) (part of Alto Jauru greenstone belt).
COMMENT: Geochemistry suggests ocean-floor basalt setting Pinho et al., 1997[689].
283 Piumhi event
Location: Brazil (São Francisco Craton)
Age: Archean
Rating: B (7)
VOLCANIC ROCKS: Piumhi greenstone belt (includes komatiites) Baars, 1997[625].
284 Khopier event
Location: W. Russia (Voronezh Uplift)
Size: 200-km-long mega-dike
Age: ??
Rating: C (possibly 5)
DIKES: Khopier, NNE trending layered intrusion mega-dike Berkovsky and Platunova, 1987[157].
285 Kolmosero-Voronye event
Location: N. Europe (Kola Craton)
Size: 650 sq. km.
Age: >2.8 Ga
Rating: B (7)
VOLCANIC ROCKS: Kolmosero-Voronye greenstone belt (includes komatiites) Kushev, 1997[690].
COMMENT: Amphibolite metamorphism at 2.7-2.8 Ga Kushev, 1997[690].
286 Krasnoyarsk continental flood basalt(C) event
Location: E. Russia
Size: 21,000 sq. km.
Age: 1.6-0.5 Ga
Rating: B (5)
DIKES: Krasnoyarsk, N trending, 1600-550 Ma Soviet Union, 1976[691] Ernst et al., 1996[117].
COMMENT: Is this part of event 81?
287 Timptono-Algamaisky continental flood basalt(C) event
Location: E. Russia (Aldan Shield)
Size: 60,000 sq. km.
Age: 1.7-1.0 Ga
Rating: B (5)
DIKES: Timptono-Algamaisky, SE trending, K 1650-1000 Ma Okrugin et al., 1995[692] Blagovyeshchenskaya, 1973[693] Ernst et al., 1996[117].
288 Kalaro-Nimnyrsky continental flood basalt(C) event
Location: E. Russia (Aldan Shield)
Size: 215,000 sq. km.
Age: 1.7-1.0 Ga
Rating: B (5)
DIKES: Kalaro-Nimnyrsky, NE trending, K 1650-1000 Ma Okrugin et al., 1995[692] Blagovyeshchenskaya, 1973[693] Ernst et al., 1996[117].
289 Seerteng event
Location: N. China (North China craton)
Size: 1200 sq. km.
Age: >2.4 Ga
Rating: B (7)
VOLCANIC ROCKS: Seerteng greenstone belt (<5 komatiites) Yuehua and Wang, 1997[694].
290 North China Craton event Zhao et al., 1999[695]
Location: N. China
Size: 320,000 sq. km.
Age: Archean
Rating: C (possibly 6)
VOLCANIC ROCKS: A-type granulites Zhao et al., 1999[695].
COMMENT: "Two metamorphic continental blocks had formed through the interaction of mantle plumes with pre-existing lithosphere in what subsequently became the eastern and western zones of the North China craton" (p. 237 Zhao et al., 1999[695]). Metavolcanic rocks.
291 Benin-Nigerian schist belt event(s)
Location: West Africa (Benin-Nigerian Shield)
Age: 1.4-0.4 Ga
Rating: C (possibly 7)
VOLCANIC ROCKS: Ife-Ilesha; Maru.
COMMENT: These are schist belts containing komatiite protoliths inferred from geochemistry and mineralogy Attoh and Ekwueme, 1997[516].
292 El Geneina event(s)
Location: Sudan
Size: 48,000 sq. km.
Age: ?
Rating: B (5)
DIKES: El Geneina, SE trending Vail, 1978[255] Vail, 1974a[696] Vail, 1974b[697] Ernst et al., 1996[117].
COMMENT: May include non-diabases Vail, 1978[255].
293 Nepoko event
Location: Congo
Size: 140,000 sq. km.
Age: ?
Rating: B (5)
DIKES: Nepoko, N trending, 1600-900 Ma Thibaut, 1982[362] Ernst et al., 1996[117], possibly 1400-1200 Ma (H. Kapmunzu, 1999, personal communication).
294 Sudan event(s)
Location: Sudan
Size: 1,800,000 sq. km.
Age: ?
Rating: B (5)
DIKES: Sudan, E trending Vail, 1978[255] Vail, 1974a[696] Vail, 1974b[697] Ernst et al., 1996[117].
295 Transvaal-3 continental flood basalt(C) event
Location: South Africa
Size: 120,000 sq. km.
Age: <1.7 Ga
Rating: B (5)
DIKES: Transvaal-3 (Kaapvaal?1), SE trending, <1700 Ma Hunter and Reid, 1987[90] Ernst et al., 1996[117].
296 Tanzania-2 event
Location: Tanzania
Age: >1.8 Ga
Rating: B (5)
DIKES: Tanzania-2, N-NNW trending, >1800 Ma Halls et al., 1987[239] Ernst et al., 1996[117].
297 Tanzania-6 event(s)
Location: Tanzania
Size: 40,000 sq. km.
Age: ?
Rating: B (5)
DIKES: Tanzania-6 (Swarm VI) , SE trending Halls et al., 1987[239] Ernst et al., 1996[117].
298 Techla event(s)
Location: Western Sahara (Morocco), Mauritania, Mali
Size: 520,000 sq. km.
Age: ?
Rating: B (5)
DIKES: Techla, E-ENE trending Mauritane (Afrique Occidentale Mauritane), 1960[698] Maroc, 1985[234] Mali, 1980[233] Ernst et al., 1996[117].
299 Uele event
Location: Zaire
Size: 280,000 sq. km.
Age: ?
Rating: B (5)
DIKES: Uele, SE trending, 2500-550 Ma Thibaut, 1982[362] Ernst et al., 1996[117].
300 Requibat Shield event
Location: West Africa (W. Requibat Shield)
Age: Archean
Rating: C (possibly 7)
VOLCANIC ROCKS: Tasiast greenstone belt Attoh and Ekwueme, 1997[516].
COMMENT: Contains meta-ultramafic rocks Attoh and Ekwueme, 1997[516].
301 Leo-Man Shield event
Location: West Africa (Leo-Man Shield)
Age: Archean
Rating: C (possibly 7)
VOLCANIC ROCKS: Greenstone belts: Sula Attoh and Ekwueme, 1997[516]; Nimini-Kambui Attoh and Ekwueme, 1997[516].
COMMENT: Ultramafic flows are highly metamorphosed Attoh and Ekwueme, 1997[516].
302 Malagasy Shield events
Location: Madagascar
Age: Archean
Rating: C (possibly 7)
VOLCANIC ROCKS: Greenstone belts Rambeloson, 1997[698a]: Maevatanana, Andriamena, Beforona-Alaotra greenstone belts are probably Archean; Dariana-Milanoa may be Proterozoic.
INTRUSIONS: Andriamena complex; Rianila complex.
COMMENT: Some soapstones after ultramafic rocks, may be meta-komatiites Rambeloson, 1997[698a].
303 McArthur Basin-1 event
Location: N. Australia (McArthur Basin)
Plume head center: ~11 S, 135 E
Size: 150,000 sq. km.
Age: ?
Rating: B (5, possibly 3)
DIKES: McArthur Basin 1 SW-S fanning swarm (p. 167 in Tucker and Boyd, 1987[699]) Boyd and Tucker, 1990[126] Ernst et al., 1996[117].
304 Pine Creek event
Location: N. Australia
Size: 45,000 sq. km.
Age: ?
Rating: B (5)
DIKES: Pine Creek, SE trending Parker et al., 1987[216] Ernst et al., 1996[117].