At http://phys.org/print358674638.html … German scientists are questioning another consensus theory, and another important piece of geological thinking. It seems the break up of the continents began around 130 million years ago. Africa and South America began to divide from each other and the mechanism is thought to have involved enormous masses of magma ascending from the deep mantle, rising to a high level of the mantle before the hot mantle plumereached the continental lithosphere, eventually leading to the split.
A paper in the journal Geology demonstrates, it is claimed, that in fact the influence of a plume on the continental crust, and sea bed, was surprisingly small – not what was expected. This seems to be another case of text book geology led by theory rather than facts. The scientists found no actual evidence of a large mantle plume – it was too small. Therefore a mantle plume could not be responsible for the break up of the super continent. Something else was to blame (which no doubt will be investigated at some stage in the future).
This is an interesting observation as we are also told that hot rising mantle plumes are an integral and important driving force within Plate Tectonics – another piece of theory led geology.
Hot mantle plumes are also supposed to have caused eruptions of large flood basalts on the continents – one of which occurs in South Africa (with some evidence of it continuing on the other side of the South Atlantic, in S America). This is what prompted the research – to find evidence of the mantle plume that was responsible for the upwelling magma (basalt). It of course may be an assumption the flood basalts date to the same time as the break up – but as they occur on both sides of the South Atlantic one might expect the magma oozed out prior to the split (but that is not mentioned in the abstract).
The piece ends up by saying, 'the role of mantle plumes during the continental break up needs to be carefully re-evaluated' – which is a polite way of saying the consensus theory has been found wanting. It seems a lot of flaws are emerging regards Plate Tectonics – yet mainstream insists that all the dots are joined up. It seems they may not be joined up at all – but then again catastrophism is avoided. One asteroid at the K/T boundary event is unwelcome – they don't want anymore exterrestrial objects slamming into the Earth.