Triassic paleomagnetic results from the Huanan Block, SE China

Abstract

Paleomagnetic and rock magnetic investigations were undertaken on samples from 14 formations in an attempt to examine the tectonic history of south China and to evaluate competing hypotheses for the amalgamation of the Huanan and Yangtze Blocks. The vast majority of the sampled sites were remagnetized; however, results from the Lower Triassic Xikou Formation appear to have escaped remagnetization. The sites pass a fold test and are in good agreement with other results published by Gilder et al. [Gilder, S., Coe, R.S., Wu, H., Kuang, G., Zhao, X., Wu, Q., 1995. Triassic paleomagnetic data from south China and their bearing on the tectonic evolution of the western circum-Pacific region. Earth Planet. Sci. Lett. 131, 269–287]. From the data, however, it is difficult to constrain the hemisphere of these sites during the Early Triassic and as such, a firm resolution of the competing hypotheses cannot yet be offered.