July 29, 2014 Earthquake: Oaxaca, Mexico

One person killed, one injured and some buildings damaged in Oaxaca. Felt (V) at Coatepec, Santa Lucia del Camino, Teotitlan and Tuxtla Gutierrez; (IV) at Boca del Rio, Coatzacoalcos, Huayapan, Jalapa, Tuzamapan and Veracruz; (III) at Mexico and Villahermosa. Felt widely in southern Mexico. Catemaco, Veracruz, Mexico - CDI: 7; Ixtaczoquitlan, Veracruz, Mexico - CDI: 7; Loma Bonita, Oaxaca, Mexico - CDI: 6; Miahuatlan, Oaxaca, Mexico - CDI: 6; Atzacan, Veracruz, Mexico - CDI: 5

Tectonic Summary

Seismotectonics of Mexico

Located atop three of the large tectonic plates, Mexico is one of the world's most seismically active regions. The relative motion of these crustal plates causes frequent earthquakes and occasional volcanic eruptions. Most of the Mexican landmass is on the westward moving North American plate. The Pacific Ocean floor south of Mexico is being carried northeastward by the underlying Cocos plate. Because oceanic crust is relatively dense, when the Pacific Ocean floor encounters the lighter continental crust of the Mexican landmass, the ocean floor is subducted beneath the North American plate creating the deep Middle American trench along Mexico's southern coast. Also as a result of this convergence, the westward moving Mexico landmass is slowed and crumpled creating the mountain ranges of southern Mexico and earthquakes near Mexico's southern coast. As the oceanic crust is pulled downward, it melts; the molten material is then forced upward through weaknesses in the overlying continental crust. This process has created a region of volcanoes across south-central Mexico known as the Cordillera Neovolcanica.

(above from reference #13456)

OAXACA - A 6.3-magnitude earthquake rattled Mexico on Tuesday, killing an elderly woman who fell as she fled her home and injuring another woman who evacuated from a hospital. The epicenter was in the east coast state of Veracruz, where residents and tourists fled homes and hotels. Authorities found no damage after reviewing the Laguna Verde nuclear power plant and oil installations in the Gulf of Mexico coast. "Only minor damage was reported in buildings" after a nationwide review of infrastructure, national civil protection coordinator Luis Felipe Puente told the Televisa network. But the earthquake claimed one life in the southern state of Oaxaca. A 75-year-old woman died after she fell and knocked her head on the floor when she was fleeing her home in the city of Oaxaca, said civil protection director Felipe Reyna Romero. Another woman broke her arm after falling while carrying a child as she fled a hospital in Oaxaca, Reyna Romero said. Walls and ceilings crumbled in the Oaxaca state cities of Tuxtepec and Loma Bonita, near the epicenter of the quake. Some hotels were evacuated in the city of Oaxaca, the state's namesake. An explosion was reported in a mine further south in San Jose del Progreso but workers were safely evacuated, Reyna Romero said. (reference #11040)