What is the relationship between faults and earthquakes? What happens to a fault when an earthquake occurs?
Earthquakes occur on faults - strike-slip earthquakes occur on strike-slip faults, normal earthquakes occur on normal faults, and thrust earthquakes occur on thrust or reverse faults. When an earthquake occurs on one of these faults, the rock on one side of the fault slips with respect to the other. The fault surface can be vertical, horizontal, or at some angle to the surface of the earth. The slip direction can also be at any angle.
I am looking to buy land near the location of a large historical earthquake. I am wondering where the fault line runs. What is the seismic activity in the area today? How did the quake change the contours and elevations of the area?
Ever since the great magnitude 9.2 earthquake shook Alaska 50 years ago today, scientists have suspected that the quake's rupture halted at the southwestern tip of Kodiak Island due to a natural barrier.
The U.S. Geological Survey has a new website that offers a virtual tour of the Hayward fault.
In a first of its kind study U.S. Geological Survey (USGS) and Duke University seismologists have used tiny "microearthquakes" along a section of California’s notorious San Andreas Fault to create unique images of the contorted geology scientists will face as they continue drilling deeper into the fault zone to construct a major earthquake "observatory.
Sunday’s magnitude 7.9 earthquake in central Alaska created a scar across the landscape for more than 145 miles, according to surveys conducted the past two days by geologists from the U.S. Geological Survey and the Alaska Division of Geological and Geophysical Survey.
Title: Underwater Secrets of the Hayward Fault Zone: Integrated 3D imaging to understand earthquake hazards
- Underwater imaging provides a unique opportunity to study urban fault hazards.
- How do we link surface structures to depths where earthquakes occur?
- How does "acoustic trenching" help us understand earthquake history?
By George Plafker, USGS Geologist Emeritus
- March 27th, 1964, one of the most violent earthquakes of all time rocked southern Alaska.
- More than 50,000 square miles of the state was tilted to new elevation, and the resulting property damage disrupted the state's economy.
- Within 24 hours, a team of USGS geologists
Two faults (located on either side of project geologist Chris Fridrich) cutting Pleistocene fluvial gravels on the northern edge of the Poncha mountain block. These and other young faults exposed in area help reveal the latest kinematic (movement) and paleostress histories of the mountain block.
This database contains information on faults and associated folds in the United States that demonstrate geological evidence of coseismic surface deformation in large earthquakes during the Quaternary (the past 1.6 million years).
Wendy McCausland of the USGS Volcano Disaster Assistance Program and Hani Zahran of the Saudi Geological Survey view the southern end of the surface fault rupture caused by a M5.4 earthquake in the Saudi Arabian desert on May 19, 2009. The ground displacements in the soft sediments of the foreground are greater than in basement rocks of the background because sediments...