Provenance of quartzarenite clasts in the Tetori Group (Middle Jurassic to Early Cretaceous), Japan: Paleogeographic implications

Abstract

There are many strata containing quartzite clasts in the Japanese Islands, but the on-land geology of the Japanese Islands has no candidate for the source rocks of the quartzite clasts. This study deals with the provenance of quartzite clasts of the Tetori Group (Middle Jurassic and Early Cretaceous) distributed in northern central Japan. Quartzarenite clasts from conglomerate beds of the Tetori Group are texturally subdivided into three types; the most abundant is matrix-bearing quartzarenite (type 3), followed by poorly sorted feldspar-bearing quartzarenite (type 2) and by well-sorted pure quartzarenite (type 1). To identify the provenance of quartzarenite clasts in the Tetori Group characteristics of quartzarenite sequences distributed in North China and Korea were studied and compared with those of the Tetori quartzarenite clasts. Texturally and geochemically, the quartzarenite clasts of the Tetori Group are very similar to pre-Mesozoic quartzarenites distributed in the south central and east central Korean Peninsula. Considering the previous results of depositional environments, paleomagnetism and paleocurrent studies on the Tetori Group, this study suggests that during deposition of the Tetori Group, the northern part of central Japan was probably land-connected with the central region of eastern Korea.