On June 12, 1978, an earthquake of magnitude 7.4 occurred with its epicenter off Miyagi Prefecture. Structures in various ports mainly in Miyagi prefecture were damaged by it, and the total cost equivalent to the damage of public port facilities and coastal facilities of the Ministry of Transport was about 3,500,000,000 Yen.
　This report presents the results of the field investigations on damage to port structures. The investigation team was organized by the government organizaitons in concern.
　This report contains data on the ground motion during the earthquake centering around accelerograms by the observation network in port area, details of damaged and undamaged structures, and other data related to damage. Facilities investigated herein are various berthing facilities, breakwaters, revetments, dock roads, quayside railway trucks. Cargo handling equipments and some facilities in Sendai airport are also included. Damage in Ishinomaki and Yuriage fishing ports are reported.
　This report does not include analysis of erthquake damage but description of damage in detail.