A BRIEF INTRODUCTION TO THE CRETACEOUS CHRONOSTRATIGRAPHIC STUDY

The present paper introduces a new progress in the studies of the Cretaceous chronostratigraphy and International Stratigraphic Chart, three ratified GSSPs and their stratotypes of Maastrichtian, Turonian and Cenomanian, as well as the definitions of GSSPs for other stages. The biostratigraphic study and radiometric dating of the Jianshangou Bed of Yixian Formation suggest the consideration of using 125 Ma as the Jurassic-Cretaceous boundary age. Also a brief comment on the Chinese Cretaceous nonmarine Furao, Nenjiang and Yixian Stages is made.