Flood Basalts: Implications for Global‐tectonic Hypotheses and Petroleum Exploration

Present geodynamic models treat the continents and ocean basins as separate tectonic domains, whereas the few coordinated attempts to extend continental geology into the deep marine basins, and vice versa, suggest that the two domains may not be so easily distinguished. Flood‐basalt provinces provide one striking example of the great similarity between parts of some continents and the deep‐sea floor. In at least two areas, continental flood basalts can be traced directly into the oceanic realm. Because of this, modern geodynamic models may have to be revised. Flood basalts also can be associated with petroleum occurrences. Three examples include the discovery of gas beneath Jurassic basalts off north western Australia, of oil beneath Late Jurassic or early Cretaceous basalts off Ghana, and of gas and oil beneath Jurassic to Triassic sills in the Middle and Upper Amazon basins of Brazil.