The Island of Guam Earthquake of August 8, 1993

Keywords: Postearthquake Investigations, Lifelines, Reinforced Concrete Buildings, Guam Earthquake, August 8, 1993, Seismicity, Economic Impact, Local Soil Conditions, Ground Effects, Liquefaction, Structural Damage, Port Facilities, and Losses.

Abstract: A magnitude 8.0 earthquake occurred 30 kilometers off the southern coast of the pacific island of Guam on Sunday, August 8, 1993. Moderate damage to structures and lifelines occurred throughout the island. Injuries were generally minor and there were no fatalities. Nearly all building structures on the island are constructed of reinforced concrete or masonry. High-rise hotels suffered the greatest effects from the earthquake. Of some two dozen high-rise structures, two or three suffered structural damage severe enough to justify demolition. Effects to lifelines on the island ranged from minor in communications systems, to moderate in electric power, water and transportation systems, and severe in the commercial port facility. The earthquake is expected to have a long term impact on the island's economy by diminished flow of material through the port, and reduced tourism. This report briefly discusses the island's tectonic setting and seismicity, and then describes the ground failure, damage to structures and damage to lifelines caused by the earthquake.