UJNR Sea Bottom Surveys Panel and its Activites

Abstract

UJNR is formally called as United States-Japan Conference on Development and Utilization of Natural Resource. This is a organization for mutual co-operation between U. S. and Japanese governmental science and technological laboratories. Now there are 16 panels under UJNR for various study fields. In these panels 6 panels are concerned with the ocean.The sea bottom surveys panel is one of them and the Japanese chairman is Dr. Akio MOGI, who is the director of surveying division, Hydrographic Department and Dr. Gordon G. LILL, Deputy director of National Ocean Survey, NOAA took the U. S. chairman's post. U. S.-Japan joint meeting is holding annually but the place is regularly changed between U. S. and Japan. Last year, 6thj oint meeting was held at Tokyo and next 7th meeting will be held at Honolulu, Hawaii on August 6 to 8, 1978.At the last meeting, there are many paper presentations which are related to sea bottom survey methods. In these papers, Dr. SATO and Dr. MALAHOFF made their presentations on submarine geology.Dr. SATO's theme is the structure and origin of the continental margin around Japanese Islands. He discussed submarine geological problems around Japanese continental margin. Continental shelf is divided into 6 types. The genesis of continental shelf is considered as erosion of eustatic sea level change during glacial age and tectonic movement. Lower continental shelf (far less than-140 m) is classified into 4 types. Continental slope and trench slope show absolute rising and absolute subsidence, which offered unsolved problems.Dr. MALAHOFF reported Baltimore Canyon Slump Sediment Project. This project was carried out at the southern part of Baltimore Canyon off Delaware Bay, U. S. Atlantic Coast side. Ordinary survey and actual observation by submergible “Alvil” were carried out. Sea bottom of the investigated area is consisted of very fine and soft sediment and it covered with older slump sediments which shaped irregular topography. This unconsolidated sediments easily moved down to lower part of continental rise.