Search results
Results from the WOW.Com Content Network
The Sierra Madre Fault Zone highlighted in red. Situated at the boundary to the San Gabriel Valley and San Fernando Valley, the Sierra Madre Fault Zone (also known as the Sierra Madre-Cucamonga Fault) runs along the southern edge of the San Gabriel Mountains for a total of 95 kilometers (59 mi), where the northwesternmost 19 km (12 mi) comprises the San Fernando Fault (the section responsible ...
The event occurred beneath the San Gabriel Mountains on the Clamshell–Sawpit Fault, which is a part of the Sierra Madre–Cucamonga Fault System. Instruments captured the event at a number of strong motion stations in Southern California .
The San Gabriel Mountains are composed of a large fault block between the San Andreas Fault Zone to the north, and the San Gabriel Fault and the Sierra Madre and Cucamonga Fault Zones to the south. [4] [5] This tectonic block was uplifted during the Miocene and has since been dissected by numerous rivers and washes. [6] [7]
A fault off the Pacific coast could devastate Washington, Oregon and Northern California with a major earthquake and tsunami. Researchers mapped it comprehensively for the first time.
Alta Loma rests on the Cucamonga-Sierra Madre Fault. [7] It is a thrust fault , meaning the sides of the fault push toward each other. Several other faults pass through the area, too, including the San Andreas Fault system, of which most of the area's faults are a part.
The frontal fault system at the base of the San Gabriel Mountains extends from the San Jacinto Fault Zone in the east to offshore Malibu in the west, and is defined primarily by moderate to shallow north-dipping faults, with a conservative vertical displacement estimated at 4,000–5,000 feet (1,200–1,500 m). [9]
The Perris Block is the central block of three major fault-bounded blocks of the northern part of the Peninsular Ranges. The Perris Block lies between the Santa Ana Block to the west and the San Jacinto Block to the east. [1] The Perris Block, was named by Walter A. English in 1925 for the city of Perris, located near the center of the block. [2]
Additionally, the Cucamonga Fault Zone, contiguous with the Sierra Madre Fault Zone, runs through the northern part of the city, along the base of the San Gabriels, notably through the Hunter's Ridge and Coyote Canyon planned communities. It is estimated to be capable of producing earthquakes approximately of magnitude 6.0-7.0. [26]