U-Pb zircon (SHRIMP) ages for the Lebombo rhyolites, South Africa: refining the duration of Karoo volcanism
Riley, T.R.; Millar, I.L.; Watkeys, M.K.; Curtis, M.L.; Leat, P.T.; Klausen, M.B.; Fanning, C.M.. 2004 U-Pb zircon (SHRIMP) ages for the Lebombo rhyolites, South Africa: refining the duration of Karoo volcanism. Journal of the Geological Society, 161 (4). 547-550. 10.1144/0016-764903-181Full text not available from this repository.
U-Pb SHRIMP ages are reported for three rhyolite flows from the Lebombo rift region of the Karoo volcanic province. Two flows are interbedded with the Sabie River Basalt Formation and a third sample is from the overlying rhyolitic Jozini Formation. The interbedded rhyolites yield ages of 182.0 +/- 2.1 and 179.9 +/- 1.8 Ma, whilst the overlying Jozini Formation rhyolite yields an age of 182.1 +/- 2.9 Ma. Combined with existing Ar-40/Ar-39 geochronology, the new SHRIMP data fine-tunes the chronology of the Karoo volcanic province and indicates the 12 km succession of volcanic rocks in the Lebombo rift were erupted in 1-2 million years and lends considerable support to the links between the Pleinsbachian-Toarcian extinction event and the global environmental impact of Karoo volcanism.
|Programmes:||BAS Programmes > Antarctic Science in the Global Context (2000-2005) > Antarctica in the Dynamic Global Plate System|
|Additional Keywords:||Lemombo rhyolites, U-pb, flood basalts, rhyolites, Karoo|
|NORA Subject Terms:||Earth Sciences|
|Date made live:||25 Jan 2012 09:59|
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