If the ocean plates are always subducted according to the geotectonics what happens to the fossils layers of the oceans. The geosyncline theory supported the theory of evolution because it could explain the vast layers of sedimentary rocks found on the contential land masses. How does the geotectonic account for the vast layers of sedimentary rocks that are found on the contential plates which have never been ocean plates.
Before explaining the relation between these two concepts; the Geotectonics and geosyncline, let me explain what these theories actually mean and why were they proposed, after that it will be easier to understand the relation between these two concepts. Geotectonic is a discipline or branch of science which deals with principles which govern form, arrangements and structure of rock masses, comprising of earths' crust and also mechanism of evolution of those features. Geotectonics is largely based on the theory of plate tectonics, which is the modern study of the major architectural features of the earth's crust. Geosyncline theory was put forward to explain how mountains form. So, it also deals with the major structural features of the earth's crust. So, there is a similarity between the plate tectonics and geosyncline theory, as both theories were put forward to interpret the geological features of earth. Nowadays many of the terms of geosyncline theory and plate tectonics are correlated to each other. So, for better understanding of Geotectonics, we must have the strong background knowledge of plate tectonics, and for understanding the plate tectonics, we must know the basics of geosyncline theory. That is how geosyncline theory and Geotectonics are related to each other.