THE THEORY OF DISPLACED TERRANES AND REGIONAL GEOLOGY

The initiation of the concept of displaced terranes is an important theoretical advance made since the application of the theory of plate tectonics on the con- tinent.Stratigraphical,paleontological and paleomagnetic data have demonstrated that some geologic bodies may follow the loci of motion of different plates over a long distance to enter other tectonic domains or biogeographic provinces.This finding has enriched the content relating to continental accretion in the theory of plate tectonics,and from this finding the author has proposed a new expla- nation for local tectonic events represented by numerous unconformities within an orogenic belts and reevaluated the significance of continental disintegration. The distinction between the global displaced terrances of various ages and reconstruction of their source areas will be the key way for the restoration of the pre-Jurassic oceanic history.The most significant point of this concept is that it has revealed the oversimplification and formularization in recognition resulting from applying indiscriminately the prevalent model of plate tectonics. It proposes that the premise that the various currently juxtaposed tectonic belts are associated in respect to space and origin is not inexorable.An analysis of basic geologic facts is reemphasized. In this paper the author systematically introduces the present views about such problems as the definition of displaced terranes,criteria of recognition, determination of the time of their assembly,superimposition and juction,and the mode and process of localization,comments on the merits and weak points of the theory,and puts forwards his own views on the relationship between the concepts of displaced terranes and plates.