An interpretation of paleomagnetic results from Cretaceous granites in South Korea.

Abstract

The mean virtual pole position for the Cretaceous granites in South Korea is close to the present geographic pole and is consistent with that for Cretaceous, Pliocene and Pleistocene volcanic rocks from the same region. It also accords with pole positions obtained from Chinese, Siberian and European Cretaceous rocks. From the paleomagnetic data for the granites and volcanic rocks of the Cretaceous, it is concluded that the South Korean land mass has not been subjected to sufficient local tectonic movements to generate a change in the direction of primary magnetic vectors of the granites or of the volcanic rocks since the Cretaceous. This means that although some tectonic movement has taken place in South Korea since the Cretaceous, the movement brought about only vertical block displacements with no significant tilting or rotational movements. It also suggests that the virtual geomagnetic pole for the Cretaceous rocks in South Korea provides a valid Cretaceous virtual pole position for the Eurasian land mass.