| Citation | Distinguished for his work on the mechanics of the earth. With R.L. Parker wrote the earliest paper on plate tectonics. Since then he has made a general study of the history of the ocean basins. His paper with Sclater on the Indian Ocean is a striking example of care and rigour in a field where there has been much sloppy work. In his paper with Morgan on the geometry of the motion of three plates on a sphere, he found a beautiful explanation of the 'great magnetic bight' in the Pacific which had been one of the principle difficulties in the acceptance of plate tectonics. Other papers study the cooling of a plate after it is formed on the ridge axis; the broad variations of ocean depth and heat flow across a ridge are accounted for. His main current interest is the theory of convection in the mantle. He also takes a leading part in work on strain and fracture in Persia. |