January 22, 2003 Tsunami: S. Mexico

A local tsunami was generated with wave heights (peak-to-trough) of about 1.2 meters at Manzanillo, 70 cm at Zihuatanejo and 25 cm at Lazaro Cardenas. A seiche was observed on Lake Pontchartrain and sediment was stirred up in wells in Louisiana. (reference #1053)

The 22 January 2003 earthquake near Colima, Mexico triggered a tsunami that was recorded at Manzaniolllo-Colima 12 minutes after the origin time of the earthquake. The tsunami was also recorded in Lazaro Cardenas-Michoacan, 200 km SE from the epicenter, and in Zihautanejo-Guerrero, 278 SE from the epicenter. Eyewitnesses interviewed by telephone the day after the earthquake reported NO tsunami in Manzanillo (report from Oceanographic Institute of the Navy), NO tsunami along the coast of Jalisco (reports from Barra de Navidad and Melaque) and NO tsunami at the Port of Lazaro Cardenas, Michoacan (report from the Captain of t he Port). Note that it was night at the time of the earthquake, which made it difficult for eyewitnesses to observe sea level fluctuations that did not overpass the higher part of the beach (the winter berm) which is on the average 1-2 meters above the high tide level along the coasts of Jalisco, Colima, and Michoacan. A field survey was conducted on January 26-28 along the coast, from La Manzanilla-Jalisco to San Juan-Michoacan, to seek tsunami traces and to determine how the people living near the coast responded to the possible tsunami. Results of the survey confirmed that no tsunami flooding occurred along the entire surveyed coast. It was also confirmed that the height of the tsunami along the coast was approximately the height of the high tide, as recorded in Manzanillo, and that it was difficult for the untrained eye to observe sea level fluctuations within the tidal range.