Where is rodgers creek fault located

Geological Survey have mapped the active surface trace of the Rodgers Creek Fault through the central part of the northern California city of Santa Rosa. Urban development has, until now, obscured its exact location. Knowing where the fault reaches the ground surface and the total width of the zone of faulting are important for assessing the hazard from surface rupture in a large earthquake.

The zone of faulting at the surface is broader and covers an area that extends farther east than previously assumed, which means the surface-rupture hazard is more widespread than previously thought. Scientists also discovered, through analysis of gravity and magnetic data, an especially dense, magnetic body of rock below the ground surface on the east side of the scarp-defined depression.

This dense, magnetic body of rock appears to be in contact with the east side of the Rodgers Creek Fault, and its northern end is associated with concentrations of small earthquakes, mainly aftershocks from the magnitude 5. Science Explorer. Multimedia Gallery. Park Passes. Technical Announcements. Another passes nearby, just east of the Community Baptist Church. Lasers mounted on an airplane were able to measure the topography with enough precision to allow researchers to observe slight changes in elevation.

Hecker likened the technology to the machines used in stores to scan barcodes. The detailed data has been used in other studies, such as one that helped the Sonoma County Water Agency know where to reinforce its water aqueduct as it passes across the fault zone. But Hecker said this is the first time the data was integrated with other information to create a detailed portrait of the urban fault zone.

The greater width of the fault zone is one key finding, Hecker said. The new maps show fault lines that now stretch east almost to Farmer's Lane. The information is useful because it can help residents understand how close their homes and businesses are to the surface faults. While all structures in the area are at risk of shaking from a major seismic event, those located on top of fault traces are exposed to additional hazards as the ground shifts, Hecker said.

By Ross Stein , Temblor. The fault also shows a sharp discontinuity right at the surface, which is very surprising in recently deposited Bay mud. It suggests that either the fault is creeping there, or there has been recent seismic slip. This means that it will be extremely difficult to prove whether such a combined rupture has happened in the past.

So, the Watt et al. The faults as they now appear in Temblor. The combined Rodgers Creek-Hayward Fault extends from Santa Rosa to San Jose both outside the frame , two cities that were also badly damaged in the earthquake.

Whenever ruptures speed up or slow down, they shed seismic energy—which we feel as strong shaking. A combined rupture could double that duration to up to seconds.