Changes in the Rotation Axis of Earth After Asteroid/Cometary Impacts and their Geological Effects

In this paper sudden shifts of the poles are proposed as an explanation for the recurrent geological crisis during which volcanic eruptions, orogenesis, climatic changes, sea levels variations, together with mass extinctions occur. Such shifts are usually considered impossible on the assumption that only a planetary impact could change in a significant way the Earth’s momentum. The position of the poles, however, is determined by the equatorial bulges; if they are “reshaped” for some reason, the poles shift without any significant change of the momentum. Due to the enormous extend of its oceans, Earth is an inherently unstable planet, so much so that a kick apparently irrelevant can trigger a process that in a very short period, that is instantaneously in geological time, provokes a reshaping of the equatorial bulge, thus making the poles shift permanently. When this happens all the masses on its surface, atmosphere, oceans and continents, are suddenly subjected to tangential forces, thus triggering a global catastrophe and long lasting effects for what concerns climate, volcanism and circulation cells of the mantle.