History of a discussion: selected aspects of the Earth expansion v. plate tectonics theories

Abstract

AbstractA global tensional system of mid-ocean ridges was discovered at the end of the 1950s. All the world's oceans were proved to be young Mesozoic–Cenozoic structures and these new ideas in geotectonics led directly to the theories of ocean floor spreading and plate tectonics. The development of the idea of ocean floor spreading proved to be a crucial turning point in modern geotectonics. These facts could suggest the expansion of the Earth. However, the view that invoked Wegener's theory of continental drift – plate tectonics – which assumed a constant size for the Earth, remained the most prevalent idea. From this point of view, plate tectonics is just a hypothesis for a non-expanding Earth. The followers of plate tectonics believe that the drift of the continents relies on their movement upon the asthenosphere. New oceanic crust has to be consumed in the so-called subduction zones, compensating for the growth of the Earth. If the process of the opening of the oceans is a unidirectional global process – and it is not compensated for – then the Earth will increase in size. The process of the widening of new oceans, such as the Atlantic, Arctic and Indian oceans, should be simultaneous with the shrinking of the Palaeo-Pacific Ocean. If the Pacific Ocean expands, then the expansion of the Earth is inevitable.