G. Tshoso

Karoo large igneous province: Brevity, origin, and relation to mass extinction questioned by new 40Ar/39Ar age data

The peak activities of continental flood basalts are currently considered as huge and brief (∼1 m.y.) magmatic events, with strong implications for geodynamics and biotic turnover. New 4 0 Ar/ 3 9 Ar dates on the Karoo flood basalts (southern Africa) show a longer duration of magmatism (∼8 m.y., with 6 m.y. for the main volume) with an apparent south-to-north migration, along with briefer distinctive pulses inside the province. This suggests that the Karoo province does not fit the general plume model invoked for most continental flood basalts (including the Karoo) and may explain the absence of a major contemporaneous mass extinction.

The Karoo Large Igneous Province: brevity, origin and relation with mass extinction in question from new 40Ar/39Ar age data.

[Riley et al. (2006a)][1] question our interpretations of 40Ar/39Ar data obtained on the Karoo flood basalts ([Jourdan, et al., 2005][2]). We believe their arguments are partially based on (1) poorly reliable 40Ar/39Ar age data (e.g., analyses of whole rocks that might have suffered hardly

The Karoo large igneous province: Brevity, origin, and relation with mass extinction questioned by new 40Ar/39Ar age data: REPLY REPLY

[Riley et al. (2006a)][1] question our interpretations of 40Ar/39Ar data obtained on the Karoo flood basalts ([Jourdan, et al., 2005][2]). We believe their arguments are partially based on (1) poorly reliable 40Ar/39Ar age data (e.g., analyses of whole rocks that might have suffered hardly

The Karoo large igneous province: Brevity, origin, and relation with mass extinction questioned by new 40Ar/39Ar age data: REPLYREPLY

[Riley et al. (2006a)][1] question our interpretations of 40Ar/39Ar data obtained on the Karoo flood basalts ([Jourdan, et al., 2005][2]). We believe their arguments are partially based on (1) poorly reliable 40Ar/39Ar age data (e.g., analyses of whole rocks that might have suffered hardly