Reconnaissance report of geotechnical observations for the 4 March 1977 Romanian earthquake

Abstract

A catastrophic earthquake struck south central Romania at 21:21 hours (9:21 p.m.) local time, March 4, 1977. The tremor collapsed 33 multistory buildings in Bucharest and damaged many other structures to varying degrees. Important damage was inflicted on many other cities and villages, particularly Craiova and Zimnicea. (For locations, see Fig. 1) Over 1,500 deaths resulted from the shock. The epicenter of the shock was preliminarily located at 45.85° N, 26.73° E with a focal depth of 110 km. A preliminary magnitude of 7.2 was assigned to the event. Aftershocks up to approximately magnitude 4 have spread south westward from the epicenter (approximately as far south as Buzau). The focal depths of aftershocks in the southern part of the zone were shallower than the main shock (as shallow as 50 km). A team of nine United States scientists and engineers was sent by the U. S. State Department to make a reconnaissance investigation of earthquake effects and damage. The team consisted of; Charles Culver (team leader) and George Fattal, National Bureau of Standards; Gerald Bowles and Fred Ruud, Bureau of Reclamation; Ernest Dodson, Army Corps of Engineers; Ted Algermissen Chris Rojahn and Les Youd, U. S. Geological Survey; and Karl Steinbrugge, Insurance Services office and a consultant to U.S.G.S. Upon arrival in Romania, the team was divided into groups which generally specialized in the following areas: Culver and Fattal investigated structural damage to buildings. Algermissen and Steinbrugge investigated the general distribution of damage and types of buildings affected in Bucharest. Dodson, Bowles and Ruud investigated damage to dams and hydroelectric power plants. Rojahn collected strong motion records and initiated discussions with the Romanians on the possible development of additional strong motion seismographs. Youd investigated damage to foundations and occurrences of ground failure (landslides, etc.). The groups worked independently of each other. However, there was communication between groups during joint meetings with various Romanian officials and in the evening hours. The purposes of this report are: 1. To summarize geotechnical effects of the earthquake. 2. To outline and justify a proposed United States Romanian cooperative geotechnical program which was considered as part of a broader cooperative program in engineering and seismology. 3. To provide a log of my travels.