Some further problems with Plate Tectonics

Evidence of Tension and Compression:

At many locations within the earth’s crust there is evidence of both tensile and compressive actions having occurred at different times (Storetvedt, 1997). This is perhaps particularly in evidence at the mid-ocean “spreading zones” where the crust is supposed to be torn apart by a tension field normal to the stripe of new crust being formed by the intrusion of magma into the fissures. As previously observed these fissures occur in bands that are broadly parallel to the mid-oceanic ridge. And yet the existence of a ridge or mid oceanic mountain ranges, sometimes involving folded sedimentary deposits, is strongly suggestive of a compression field action normal to the ridge, and Antipov et al (1990) have suggested that thrust faults adjacent to the mid-Atlantic ridge are more likely to have been caused by compression rather than tension. Fracture patterns are also suggestive of compression related failures in the vicinity of the spreading zone. Zoback et al (1989) demonstrated that earthquake data at mid oceanic ridges is more strongly supportive of compression action than as supposed by PT from tension behaviour. It would appear that alternations of both tension and compression actions are experienced in locations where PT would indicate steadily developing tensile failure. PT appears to have little on offer to resolve these apparent contradictions (Pratt, 2000).

Vertical Tectonics:

It should not take long for even an untrained geologist to become concerned about the fact that many of the highest continental mountain ranges and some of the most extensive continental plateau, are formed from sedimentary rock that was once laid down at the bottom of an ocean floor. Equally, as observed above considerable areas of deep, ocean floor are composed of rock whose palaeontological evidence alone indicates that it once formed part of a continental land mass (Spencer, 1977). PT does not appear to have addressed these issues and seemingly would be hard pushed to provide an explanation for this very clear piece of geological reality. That marine sediments and fossils can be found near the highest peaks of the Himalayas or that shallow sediments and even land based fossils can be recovered from the depths of ocean crust, are inconsistent with any notions that currently form part of PT (Pratt, 2000). Explanations based upon changes in sea level, believed to be brought about by increased volumes of uplift at the mid-oceanic ridges, has been suggested by an acknowledged supporter of PT  to be an inadequate explanation, and that the scale of these movements “fit poorly into plate tectonics” (van Andel, 1994).

Much of the above post has been taken from the paper "On the Causes of Vertical Motions of Lithosphere", James G A Croll, Frontiers meeting, Geological Society of London, November, 2011.