The recent paper by De Wit et al. (2020) presents the radical thesis that eruption of the earliest basalts of the Karoo Supergroup, hereafter Karoo basalts, now preserved in the Lesotho remnant, occurred in a deep marine environment (>200 m water depth). On this is developed a tectonic model of early rifting between South Africa and Antarctica beneath a major seaway. This discussion focusses on evidence relating to Karoo lava emplacement and rejects the submarine eruption proposal. I do not deal with details of the tectonic model. However, it hangs on the submarine eruption proposal and, if the...

You do not currently have access to this article.