Historic Earthquakes

South of the Mariana Islands
1993 August 08 08:34:24 UTC
Magnitude 7.8

South of the Mariana Islands Earthquake
Largest earthquake in 1993.

Forty-eight people injured on Guam. Extensive damage (IX) to hotels in the Tumon Bay area. Cracks tens of meters long and 25-50 cm wide, caused by liquefaction in the underlying soil, damaged facilities at the commercial port and naval base at Apra Harbor. Damage (VII) occurred at several locations in the northern half of the island. One end of the approach to a bridge at Pago Bay fell more than 35 cm. Many landslides and rockslides were reported, mainly in the southern half of the island. The preliminary estimate of loss from damage to commercial buildings is placed at 112 million U.S. dollars and loss from damage to private residences is estimated at several million U.S. dollars. Slight damage (V) on Saipan. Felt (VI) on Rota and (V) on Tinian. Tsunami generated with maximum wave heights at selected tide stations as follows: 98 cm at Muroto-misaki, Shikoku; 68 cm on Chichi-shima, Bonin Islands; 58 cm at Tosashimizu, Shikoku; 56 cm at Aburatsu, Kyushu; 46 cm at Mera and Owase, Honshu; 44 cm at Ayukawahama, Honshu; 42 cm at Omae-zaki, Honshu; 34 cm at Hanasaki and Kushimoto, Honshu, 34 cm at Hirara, Ryukyu Islands; 28 cm at Ofunato, Honshu; 24 cm at Kochi, Shikoku; 19 cm at Port Allen, Kauai; 15 cm at Lahania, Maui; 14 cm at Haleiwa, Oahu; 12 cm at Hachinohe, Honshu and Kahului, Maui; 7 cm at Kapoho, Hawaii and Nawiliwili, Kauai; 5 cm at Honokohau, Hawaii.

Abridged from Significant Earthquakes of the World, 1993.