July 15, 2013 - SOUTH SANDWICH ISLANDS - A 7.3 magnitude earthquake has struck south of Bristol Island in the South Sandwich Islands. No tsunami alert exists, however.
The massive 7.3 magnitude earthquake began today July 15, 2013 far out to sea, far from Argentina and Chile’s coast, officials tell news. It was initially reported as a 6.8 magnitude quake before being upgraded.
The large earthquake today began moments ago. It erupted at 12:03 pm local time, officials tell news. It also posted a moderate depth. USGS indicates to news that the quake starting twenty miles below sea level. But the quake was far from land when it began. Officials tell news that the quake was closest only to one island.
The quake began one hundred thirty miles southeast of Bristol Island in the South Sandwich Islands. The quake was thereafter a great distance from other nations. The quake was one thousand six hundred miles at least from Ushuaia, Argentina. It was roughly one thousand seven hundred miles from Rio Gallegos in Argentina as well.
Reps tell news that the quake was about one thousand seven hundred miles from Punta Arenas, Chile and about one thousand three hundred mils from Stanley in the Falkland Islands.
The National Weather Service says that no tsunami danger exists currently for the U.S, Gulf of Mexico, Puerto Rico and Virgin Islands. But officials. Both the Alaska Tsunami Warning Center and the Pacific Tsunami Warning Center confirm that no tsunami threat is in place. - LA Late.
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USGS earthquake location. |
The massive 7.3 magnitude earthquake began today July 15, 2013 far out to sea, far from Argentina and Chile’s coast, officials tell news. It was initially reported as a 6.8 magnitude quake before being upgraded.
The large earthquake today began moments ago. It erupted at 12:03 pm local time, officials tell news. It also posted a moderate depth. USGS indicates to news that the quake starting twenty miles below sea level. But the quake was far from land when it began. Officials tell news that the quake was closest only to one island.
The quake began one hundred thirty miles southeast of Bristol Island in the South Sandwich Islands. The quake was thereafter a great distance from other nations. The quake was one thousand six hundred miles at least from Ushuaia, Argentina. It was roughly one thousand seven hundred miles from Rio Gallegos in Argentina as well.
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USGS earthquake shakemap intensity. |
Reps tell news that the quake was about one thousand seven hundred miles from Punta Arenas, Chile and about one thousand three hundred mils from Stanley in the Falkland Islands.
The National Weather Service says that no tsunami danger exists currently for the U.S, Gulf of Mexico, Puerto Rico and Virgin Islands. But officials. Both the Alaska Tsunami Warning Center and the Pacific Tsunami Warning Center confirm that no tsunami threat is in place. - LA Late.
Tectonic Summary
The July 15, 2013 Mw7.3 South Sandwich Islands earthquake occurred as a result of either east-west left-lateral or north-south right-lateral strike slip motion at shallow oceanic crustal depths. The earthquake occurred ~100km east of a complex plate triple junction between the South America, Antarctica, and Sandwich plates. The South America plate currently subducts beneath the Sandwich plate at a rate of ~13mm/yr while sliding past the Antarctica plate with left-lateral motion along the South Sandwich Fracture Zone at a rate of ~14mm/yr. Given the strike slip nature and location of the event, the earthquake likely resulted from relative motion between the South America and Antarctica plates. Several large earthquakes have occurred along this portion of the plate boundary, including events of Mw7.4 in January 2006 and Mw7.5 in October 1973. - USGS.