Abstract
The Momonoki geological tectonic province sits between two uplifted massifs, Akaishi and Kushigatayama. It is almost composed of the clastic rocks intercalated with a thin limestone bed and is made up of three sedimentary bodies; Gozaishi Nepton, Ashiyasu Nepton and Mogura Nepton. These are superimposed on each other in this order from the north. Clastic rock layers composed of these Neptons are deformed intensely folding and faulting. The author gained the shapes of folds in vertical plane (geological section) excepting disorder of the sedimentary layers by faulting because the folding may come before the faulting in the Momonoki geological tectonic province. Folds in the same province are divided into four groups according to their morphology, based on the wavelength in vertical plan; its features are as follows: 1. Folds which belong with the same group develop in the belt that strikes from north to south and from NNE to SSW. 2. Shapes of the major folds become complex to the north. 3. Minor folds develop in the belt on the west. 4. Kink folds develop in a limited area; marginal area of the H66 granitic body and the vicinity of the Itoigawa-Shizuoka tectonic line.
