Japan earthquake fault may have slipped some 40 metres

March 13th, 2011 - 1:47 pm ICT by ANI  

London, Mar 13 (ANI): The massive earthquake - one of the largest ever recorded - that struck Japan last week appears to have moved the area of fault by about 40 metres and not as large as expected, according to a researcher of the University of California.

The area of fault that ruptured was actually small, within a length between 300 and 400 km. In comparison, the magnitude 9.1 Sumatra earthquake in 2004 broke along an area of fault 1,300 km long.

Then, why was the quake so strong? According to a calculation by Chen Ji, it happens when two adjoining tectonic plates shifted along the 40 meters.

To arrive at this figure, Ji downloaded information about when seismic waves arrived at stations around the world, and then reversed the data to where along the fault the seismic energy was generated.

His calculations stated that an area of fault between 300 and 400 km long by 100 km wide slipped some 40 metres.

Meanwhile, the U.S. Geological Survey has estimated an area of fault closer to 20 metres.

Either way, it is apparent that it has implications for future quakes in the region, as the pressure released during the quake is likely to have transferred to other faults nearby.

“There is no doubt this quake increased stress conditions and the potential for the fault to break both to the south and north of this event. It could be a few months, or it could be a few years,” Ji told New Scientist.

Ji’s calculation is expected to provide detailed information at how the quake that spawned the disaster unfolded. (ANI)

Related Stories

Tags: , , , , , , , , , , , , , , , , , ,

Posted in Health Science |

Subscribe