Strong Quake Strikes Off the Coast Mexico

Magnitude 6.4 Earthquake Strikes Off the Coast of Jalisco,Mexico

Strong earthquake measuring 6.4 Mw struck off SW of Puerto Vallarta, Jalisco, Mexico, at a depth of 35 km, on Thursday,  September 24, 2009, at 07:16 UTC, USGS/EHP reported.

This event will almost certainly affect the outcome of the FEWW northern California earthquake forecast.

The earthquake was preceded by a foreshock measuring 5.6Mw which occurred on Friday,  September 18,  2009, at 18:46 UTC.

FEWW Comments: This earthquake may have primed for eruption either one or both of two volcanoes Bárcena, which forms the island of San Benedicto, and Socorro, located on island of the same name, about 380 km to the west of the EQ location.

10-degree Map Centered at 20°N,105°W

EQ Location Map. Source: USGS

This Earthquake:

• Magnitude: 6.4
• Date/Time: Thursday, September 24, 2009 at 07:16:24 UTC [Thursday, September 24, 2009 at 12:16:24 AM at epicenter]
• Location: 18.992°N, 107.350°W
• Depth: 35 km (21.7 miles)
• Region: OFF THE COAST OF JALISCO, MEXICO
• Distances:
  • 285 km (175 miles) SW of Puerto Vallarta, Jalisco, Mexico
  • 315 km (195 miles) W of Manzanillo, Colima, Mexico
  • 325 km (200 miles) WSW of Autlan, Jalisco, Mexico
  • 855 km (530 miles) W of MEXICO CITY, D.F., Mexico
• Location Uncertainty:  horizontal +/- 6.5 km (4.0 miles)
• Source: USGS NEIC (WDCS-D)
• Event ID: us2009lyat

The associated Press quoted the USGS as follows:

The U.S. Geological survey says the temblor struck about 170 miles (275 kilometers) southwest of Puerto Vallarta at 0716 GMT (3:16 a.m. EDT) Thursday. It occurred at a depth of about 2.5 miles (4 kilometers).

Tsunami Bulletin:

PACIFIC TSUNAMI WARNING CENTER/NOAA/NWS
Issued the following at 07:28UTC 24 SEP 2009

AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY PARAMETERS

ORIGIN TIME –  0716Z 24 SEP 2009
COORDINATES –  19.1 NORTH  107.3 WEST
DEPTH       –   10 KM
LOCATION    –  OFF COAST OF JALISCO  MEXICO
MAGNITUDE   –  6.7

EVALUATION

NO DESTRUCTIVE WIDESPREAD TSUNAMI THREAT EXISTS BASED ON
HISTORICAL EARTHQUAKE AND TSUNAMI DATA.

HOWEVER – EARTHQUAKES OF THIS SIZE SOMETIMES GENERATE LOCAL
TSUNAMIS THAT CAN BE DESTRUCTIVE ALONG COASTS LOCATED WITHIN
A HUNDRED KILOMETERS OF THE EARTHQUAKE EPICENTER. AUTHORITIES
IN THE REGION OF THE EPICENTER SHOULD BE AWARE OF THIS
POSSIBILITY AND TAKE APPROPRIATE ACTION.

THIS WILL BE THE ONLY BULLETIN ISSUED FOR THIS EVENT UNLESS
ADDITIONAL INFORMATION BECOMES AVAILABLE.

Related Links:

• California Earthquake Forecast – Update 3
• FEWW Earthquake Links
• Magnitude 6.9 Quake Strikes Gulf of California

• FEWW Earthquake Forecast: Near Mexico City