India's deadliest earthquake still provides valuable informationfor researchers three years later, said University of Memphisprofessor and study author.
Paul Rydelek, an associate research professor of geophysics atThe University's Center for Earthquake and Research and Information(CERI), has published his findings on a three-year-old Indianearthquake in the scientific journal, Nature.
"It is very rewarding to get this highly visible communicationin Nature," Rydelek said.
The earthquake, which occurred in January 2001 in the Indianvillage of Bhuj and registered a magnitude of 7.7, was India'sdeadliest and most destructive earthquake in recorded history.
Initially, the study originated with a team of faculty membersfrom The University's CERI to research aftershocks of the Indianearthquake. Upon arrival, Rydelek further studied the two cratersfound 30 miles outside of Bhuj, in a village called Umedpur.
"The dry craters were unlike anything we'd ever seen before,"Rydelek said.
Using basic physics, Rydelek estimated the pressure involved toform such craters. The crater exploded and threw sediments 80 feetaway.
A phenomenon called liquefaction caused the sediment and rock toexplode to form these craters.
Liquefaction is the movement of water from high-pressured areasto low pressured areas, which carries high amounts of sediment inthe process. This movement, which takes place during the violateshaking of a quake, can also cause gas to rise to the surface andexplode.
After liquefaction occurred, the ground exploded, causing thetwo craters to form.
Even though liquefaction is not uncommon during violateearthquakes, explosive craters are not a common result of thisprocess.
The craters that were found measure 5 to 6 feet in diameter.
"The explosion is similar to the explosion of dynamite in theground," Rydelek said.
The eruption of sediments that form craters is rare because itrequires intense ground movement, certain soil types and specificwater table settings.
The quake in western India provides interesting facts aboutliquefaction and its results but also provides insight on pastMid-South earthquakes.
The earthquakes of 1811 and 1812 in the Memphis area weresimilar to this Indian quake.
"This Indian earthquake is similar to that of New Madridearthquakes in 1811 and 1812 because the deep sediments resembleeach other geologically," Rydelek said.
