The Quaternary sediments in the Atsumi district can be divided into four stages, each reflecting a submergence, same as other areas in the Tôkai region. The earliest stage is the Atsumi formation which is considered to be a deltaic deposit of the ancient River Tenryû. Its molluscan fauna indicates a large shallow bay such as present Ise Bay, and neither a small inlet nor an open sea. The fauna is quite different from the present community of the south open coast of the peninsula. It might be surmized either the Shima Peninsula was further projected to the east at that time or the like of a peninsula existed at that time to the south of the present Atsumi Peninsula, preventing the ancient large bay from free communication with the south open sea. An up-warping movement has been taking place on the Atsumi Peninsula since the early Pleistocene. The brachy-anticline thus produced agrees with the present topography of the peninsula, and reveals close resemblance to those of Udo hill and Makinohara area in the Tôkai region.
The genus Coriaria, the one of the archaetypic angiosperms, has very peculiar distributional areas (Fig.1), and it is noteworthy that these areas can be nearly included in the girdle along the one of the great circles of the globe (Fig. 2). In this day there is good proof, from the palaeo-magnetic studies, of the pole wandering and the continental drift in the past. Beside this, the author accepts the hypothesis in which the new large groups of plant have been usually originated in tropical and/or subtropical montane regions and the angiosperm also is not the exception. With the aids of these conceptions, the author realizes that the present Coriaria's areas are the remnant scar of its aboriginal distributional range where the genus had started and developed but later discarded principally by the continental drift in the new world and disjuncted through the extinction induced by the enlargement of desert areas in the western and central parts of gerontogea and also by the development of the ice-covering. This palaeotropical and palaeosubtropical montane girdle, I should say, had covered the large areas, from South America to New Zealand, through in sequence, eastern North America, western North Africa, Europe, northern Central Asia, South-eastern Asia and Melanesia and had been the starting bed of probably most of the ancestors of the recent angiosperm, which might be expected to start there already as early as the later Palaeozoic Era. Lardizabalaceae (Asiatic monsoon area and Chile) and Mitrastemon (SE Asia and Mexico-Guatemala) are the other good examples. Eastern Asia (Himalaya-Sino-Japanese element) and Eastern North America (Appalachian element) are famous with having in common many temperate genera of old type and the author considers that they surely belong to the same category.
The Quaternery deposits of Sendai and its environs from stratigraphical and geomorphological studies are divided into several formations and terraces, respectively. The stratigraphic units recognized are the Pleistocene Motoisago gravel, the Aobayama formation, the Dainohara terrace deposits, the upper Sendai terrace deposits, the middle Sendai terrace deposits, the Holocene lower Sendai terrace deposits, and the Miyagino-hara coastal plain deposits. The depositional planes of each of the mentioned formations are preserved and represented by the successive terrace surfaces. Stratigraphical evidence of the volcanic ash layers in this area proved them to be useful guides for correlation of the sequences of the respective terraces developed along the different drainage systems. The volcanic ash layers, four in total, are given formal names and each is related with a different terrace level, as follows. The Koeji ash is accompanied with the Aobayama formation, the Medeshima ash with the Dainohara terrace deposits, the Hirasawa ash with the Hara terrace deposits, and the Nagano ash with the Nagano terrace deposits. From stratigraphical and geomorphological features correlation of the deposits and the terraces is undertaken with the result shown in Table. Details concerning the above mentioned are given in the text.
The results of surveying of Kamogawa Submarine Canyon are as follows; a) Drainage system is very simple; the canyon is nearly straight in the area deeper than 300m, and is divided into three tributaries in shallower than 300m. b) Transverse profiles are V-shaped and are without terraces. c) Longitudinal profile does not show the equilibrium curve. d) In the upper stream, wall is rocky or covered thin mud sediment, and valley bottom is muddy. In the down stream, it is generally muddy. e) The distribution of rock is divided to three regions; shallower than. 20m off the abrasion cliffs, walls of canyon and spur just south of the canyon. f) Almost of the rocks dredged are correlated to the Hota Group (lower Miocene). They are dark greyish mudstone, tuff and tuffaceous sandstone. The rocks dredged from the wall of the tributary off Futomi, are compact sandstone and black slate which are correlated to the Mineoka (so-called unkwon Mesozoic).