Sedimentological Studies of the Tetori Group in the Upper Reaches of the Sho River, Gifu Prefecture, Central Japan

岐阜县昭川村晚侏罗世至早白垩世的鸟鸟群分为8组，它们之间相互整合。群的沉积环境由浅海海湾向水漫或辫状河平原转变，并有一定的起伏。对四鸟群砾岩和砂岩的模态组成进行了定量和系统的研究，表明烃源地主要由花岗岩和成因组成，但有时与盆地附近古生代至中生代沉积岩或前寒武纪的长石英岩有关。这些腹地的变化可能与日本列岛晚侏罗世至早白垩世的构造运动有关。

The late Jurassic to early Cretaceous Tetori Group in the Shokawa Village,Gifu Prefecture is divided into eight formations which have conformable relationship with each other. The sedimentary environments of the group changed from a shallow marine bay to meadering or braided river plain with some fluctuations. The modal composition of conglomerates and sandstones of the Tetori Group investigated quantitatively and systematically indicates that the source lands were composed mainly of granite and geneses, but sometime associated with Paleozoic to Mesozoic sedimentary rocks or Precambrian othoquartzites near the basin. These changes of the hinterland might be related to the tectonic movements in the Latest Jurassic to Early Cretaceous time in Japanese Islands.