The author made a geographical field survey in Northwestern India as a member of the research team organized by the University of Hiroshima during the period from September 1972 to January 1973. The purpose of this paper is to elucidate the geomorphic history, tectonic movement and the sequence of climatic changes in the Punjab Plains and the northern part of the Thar Desert. The results obtained may be summarized as follows : 1) The three physiographic divisions of alluvial plains are based on the characteristics of the surface features : dissected piedmont plain, alluvial upland and alluvial lowland (Fig. 1). The alluvial lowland is divided into two geomorphic units : active flood plain and abandoned flood plain. Abandoned flood plain in developed parallel to the river courses and is three metres higher than the active flood plain. It is often inundated by high floods. The alluvial upland is bordered by steep scarps, with relative heights of 1.5-12 metres above abandoned flood plain. Radiocarbon date on fossil shells suggests that the dissection of the alluvial upland has taken place within at most the last 4, 000 years. 2) The flat alluvial plains of the Punjab in India have been formed by the deposition of the Indo-Gangetic alluvium, of which maximum thickness amounts to 300 metres above the basal rocks of the Siwalik Systems. The alluvial complex of the Pleistocene and Holocene age consists of fine to coarse sand, silt and clay. The recognition of paleosols and calcium carbonate deposits (kankar) allows the classification of the alluvial complex into three formations, which are upper, middle and lower alluvium. The rate of sedimentation of alluvial deposits are estimeted at 0.25-0.33 mm per year in Ludhiana district in the Punjab Malwa. The upper formation may be correlated with the Holocene based on this calculation (Table 1). The fossil shells mentioned above in the clay (UCL) of the upper formation constituting a top layer of alluvial upland give a radiocarbon date (GaK-5838) of 4, 300±150 years B.P. Radiocarbon dating appears to support this calculation. 3) Deformed alluvium shows the folded structure with the axis of NW-SE direction about 40 km in length parallel to the axis of folded structure of the Siwalik Hills in the Punjab Malwa and Bist doab. It seems that this tectonic movement has been continuous since the middle Pleistocene. It may be evidence for the tectonic movement that the distribution of saline soils and drainage patterns of Whitebein River coincide with the axis of cryptsyncline. 4) Riverine sand dunes are extensively distributed on the alluvial upland in the Punjab Malwa. These riverine sand dunes were formed along the channel scars of the Sutlej River. On the other hand, sand dunes develop very seldom in the Kurukshetra Plain. This may reflect the difference in geology of the drainage areas in the upper reaches of the Sutlej and the Yamuna River. The distributional patterns of sand dunes and channel scars show the following : the Sutlej River has been shifting toward NW direction and Yamuna River shifting toward SE direction. As a result of the shifting of the river course of the Sutlej or the Yamuna, Kalibangan and the other settlements in the Indus Culture along the abandoned river course deserted about 3, 700 years ago. These shiftings may be caused by the tectonic movement in the Punjab Malwa and the Kurukshetra Plain. The riverine sand dunes are divided into two systems : fixed sand dunes and active sand dunes. The active sand dunes have been formed on the fixed sand dunes by modern cultivation since the 19 th Century. The buried animal bone which was exhumed from a buried trench cutting into the fixed sand dunes gives a radiocarbone date (N-2233) of 435±115 years B.P. This fixed sand dune is overlain the active dund sand 3 metres thick.
The surveys of submarine topography, geology, geomagnetism and gravity were conducted off the coast of Kyusyu by the Hydrographic Department, Maritime Safety Agency, Japan in 1973 and 1974. On the basis of these surveys, the authors described the general features of the submarine topography and the geological structure, and discussed the geological history of Goto Submarine Valley and Danjo Basin, being remarkable topographies in the studied area. General trends of geological structures are as follows. 1. The faults and folds of basement in Tokai Continetal Shelf have NNE-SSW trend. 2. Trains of banks and islands, such as Goto Islands, Danjo Islands and Kosiki Islands, and also strikes of fold axes of the sedimentary layer in Okinawa Trough shows NE-SW trend. 3. The faults which are parellel to elongation axis of Danjo Basin in Okinawa Trough have ENE-WSW trend. 4. Faults which transverse the trends mentioned above show NW-SE trend and this trend is remarkably in Goto Submarine Valley area. Trends of NW-SE, NNW-SSE, NE-SW and ENE-WSW had been formed in the Late Miocene. In this time, the original shapes of Nisi-Goto Shelf Channels and Fukue Basin were formed at the outer ridge and its surroundings of Tokai Continental Shelf, developing in parallel with the tectonic lines of NW-SE trend. And also, Goto Submarine Valley initially incised the sea bottom between Danjo and Goto Islands in the Late Miocene, and developed during the Pleistocene age. The framework of Danjo Basin was cotorolled with the trends of NW-SE, NE-SW and ENE-WSW, and the basin was formed by the synclinal subsidence in the Plio-Pleistocene.
Continued from No. 3, Vol. 82 (1973) of this Journal in which the outline of the Joint Hydrographic Surverys in the Straits of Malacca and Singapore up to the 2nd detailed survey was reported, an account is given to the rest of the project, i.e. the 3rd and 4th detailed surveys. (4) 3rd detailed hydrographic survey. In 1973, the 3rd detailed survey was carried out in the areas shown in Fig. 1. As the result, uncharted shoals with depths of less than 23 metres were revealed to exist 10 in Area IV-A and 16 in Area IV-B. Furthermore, out of those shoals with depths of 23 metres charted according to ships' reports, 11 were confirmed not to exist. (5) 4th detailed hydrographic survey. In 1974, the survey was conducted in the areas shown in Fig. 2 and Fig. 3. uncharted shoals with depths of less than 23 metres were revealed to exist 2 in Area IV-D, 3 in Area IV-E and 14 in Area V. In Area IV-D, existence of a sunken wreck was confirmed, while in Area V, 3 charted shoals were confirmed not to exist. *** It is remarked that the results of the Joint Hydrographic Surveys were all adoped on the nautical charts published by the Hydrographic Department of Japan.