Tuesday, March 20, 2012
18:02:48 UTC
2010 April 04
22:40:42 UTC
Magnitude 7.2 temblor caused by same tectonic shifts that created Baja Peninsula (click here)
for National Geographic News
Published April 5, 2010
The magnitude 7.2 earthquake that jolted northern Mexico and Southern California yesterday afternoon was the first big earthquake to occur on this particular fault system since 1892, scientists say....
It seems to have a wide spread shake pattern. I can't help but wonder the relationship between this quake and the rather complicated quake in 2010.
March 20, 2012 2:25 PM
7.4 quake hits near Acapulco, Mexico (click here)
...A pedestrian bridge collapsed and crushed a microbus in Mexico City, but there were still no reports of deaths. A building in the neighborhood of Condesa appeared to be on the verge of collapsing.
The quake was felt strongly in southern Guerrero state, where the epicenter was located about 15 miles (25 kilometers) from the city of Ometepec. Neighboring Oaxaca state also shook heavily, including with two aftershocks.
Governors in both states reported on their Twitter accounts that there were not major reports of damage....
The two quakes could be related through the Cocos Plate and North American Plate. The seismic activity, 7.4 and 7.2, seems to similar to exclude that potential.
08/11/11
New data shows El Mayor–Cucapah earthquake was simple on surface, complicated at depth (click title to entry - thank you)
...The El Mayor–Cucapah earthquake happened along a system of faults that run from Southern California into Mexico, cutting through the Cucapah mountain range and across the Colorado River delta. This system of faults forms a portion of the plate boundary between the Pacific Plate and the North American Plate. Two main segments of the fault tilt downward steeply from the surface at opposing angles: the northwestern half angles downward beneath the Mexicali Valley, whereas the southeastern half angles away from the valley.In a standard model, transform plate boundary structures—where two plates slide past one another—tend to be vertically oriented, which allows for lateral side-by-side shear fault motion. In the case of this quake, however, lead author Shengji Wei, a postdoctoral scholar in geophysics, and colleagues showed that the 120-kilometer-long rupture involved angled, non-vertical faults and that the event was initiated on a connecting extension fault between the two segments....
August 11, 2011
PASADENA, Calif.- Like scars that remain on the skin long after a wound has healed, earthquake fault lines can be traced on Earth's surface long after their initial rupture. Typically, this line of intersection is more complicated at the surface than at depth. But a new study of the April 4, 2010, El Mayor-Cucapah earthquake in Baja California, Mexico, reveals a reversal of this trend. Superficially, the fault involved in the magnitude 7.2 earthquake appeared to be straight, but at depth, it's warped and complicated. The study, which was led by researchers at the California Institute of Technology with NASA Jet Propulsion Laboratory geophysicist Eric Fielding serving as a coauthor, is available online in the journal Nature Geoscience....
