A number of inexplicable earthquakes occurred near Mineral, Virginia in the US that has researchers baffled, since earthquakes are not supposed to occur in the middle of tectonic plates away from subduction zones.
Rather than question the prevailing paradigm of plate tectonics, the researchers instead have proposed that pieces of the Earth’s mantle are breaking off and sinking into the planet.
The cause is from plate motion in which bits and pieces of the underside of the plate break off and sink down. It’s called piecemeal delamination.
There are problems with this explanation.
1. Tectonic plates are of lower density than the higher density mantle, therefore bits and pieces can’t ‘fall down into’ the mantle.
2. Earthquakes are caused by rock-slippage? Might be observed at the surface when brittle failure is observed, but at depth any movement is caused by plastic flow, and that can’t generate earthquakes.
3. Isn’t pressure supposed to increase with depth according to planetary self accretion? If so, less dense cannot fall into more dense.
In any case the scientific approach is to accept that intraplate earthquakes occur and then start questioning the theory of plate tectonics, and not make ad hoc adjustments to the prevailing theory to explain anomalies.
A similar geological event happened during the 1960’s in the Archaean craton of the Murchison province of Western Australia. Then an earthquake occurred and a large normal fault and subsidence was observed near Wooleen station. This is not supposed to happen to stable cratonic blocks well away from subduction zones.
It remains inexplicable.
Ya reckon the theory of plate tectonics might be the problem?
Update: (Tectonic plates slide over the mantle, so bits and pieces of the mantle can’t fall into the mantle since it’s underneath the plate from which the pieces are breaking off from)