A Defense of an “Old Global Tectonics”1
Many aspects of the so-called “new global tectonics” or plate-tectonics theory were proposed by geologists three or more decades ago. Included among these concepts are continental drift, the worldwide continuity of the midocean ridge and rise system, seafloor spreading, underthrusting of oceanic crust along trenches and the concept of subduction, collision of continental plates to form Alpine-type mountains, and the concept of plate tectonics itself. Geologists who perceptively formulated theories of worldwide interrelations between extensional zones and compressional belts include Daly, Du Toit, Griggs, and Holmes.
What was lacking for an initial broad acceptance or refutation of any concept of global tectonics was adequate supporting data, primarily of a geophysical nature and particularly from the vast oceanic regions. The recent geophysical contributions in the formulation of plate-tectonics theory are significant, but the essential role of geology and the imaginative contributions of earlier geologists in the formulation of many concepts basic to plate tectonics should not be minimized or forgotten.
Figures & Tables
The general theme of this publication is the assessment and reassessment of various data, observations, and ideas about the earth as they relate to the concept that has come to be known as plate tectonics. Much widely scattered material was brought together for this publication, and its 24 papers contain an abundance of worldwide references that are important in studying plate tectonics.