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Detailed geochemical and field data for the volcanic sequence and intrusions of the Etendeka Igneous Province are used to construct a stratigraphic framework for petrogenetic interpretation of the evolution of the Etendeka-Paranµ continental flood volcanic event. Geochemical and petrographic characterization of over 1,000 analyzed samples allows 8 mafic and 17 silicic magma types to be recognized. Both silicic and mafic types can be grouped into high-Ti and low-Ti suites on the basis of elevated Ti relative to other elements. The mafic magmas are: Khumib (highTi), Tafelberg, Kuidas, Horingbaai, Huab, Tafelkop, Albin, and Esmeralda (all low-Ti). Amongst the silicic types, the Goboboseb, Springbok, Wereldsend, Grootberg, and Beacon low-Ti quartz latites, and the Nil Desperandum high-Ti latite have been described previously. In addition, the Hoas (low-Ti), Nadas, Sechomib, and Hoarusib, (all high-Ti) latites and the Fria (low-Ti), Sarusas, Ventura, Khoraseb, NaudØ, and Elliott (all high-Ti) quartz latites are described for the Keywords Etendeka-Paranµ province´Magma typesV olcanic stratigraphy´Flood basalt´Silicic volcanics J.S. Marsh ( ) )

[1] We have carried out paleomagnetic sampling of a ∼750 m sequence of the Karoo large igneous province (Naude's Nek Pass, South Africa). K-Ar dating (Cassignol-Gillot) has been performed on four samples from the 650 m upper unit (mean age 179.2 ± 1.8 Ma) and a sample from the lower unit (184.8 ± 2.6 Ma). A succession of two phases of volcanism is suggested. The lower 25 flows (115 m thick) have recorded a reversed polarity; the next 23 flows (135 m thick) are transitional and contribute a detailed record of the "Van Zijl" (1962) Jurassic reversal. The upper 38 flows (500 m thick) have normal polarity. Directional groups (DGs) of lava flows with quasi-identical remanence directions indicate eruption durations too short to have recorded geomagnetic secular variation and hence are interpreted as single eruptive events. Altogether, 19 DGs and 10 sheet lobes yield a sequence of 29 distinct directions. This could correspond to a total eruptive activity shorter than 3000 years, less than one per mil of the total duration over which the section was emplaced. We obtain a new paleomagnetic pole for South Africa at ∼180 Ma (l = 75.2°N, ' = 276.4°E, A 95 = 5.8°, N = 19), which is consistent with earlier reports.

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