Source AP ©

Scientists show first rock samples from borehole in San Andreas Fault in California

Trying to better understand how earthquakes are born, scientists showed off the first rock samples taken from a borehole being drilled into the mighty San Andreas Fault in California.

The borehole is a step toward creating the world's first underground earthquake observatory designed to study temblors up close.

Researchers hope the rock core collection, weighing about a ton (1 metric ton) in total, will help answer questions about the fault's makeup and determine what happens during stress buildup at great depths.

"These are kind of like moon rocks for people studying earthquake mechanics," said Stephen Hickman of the U.S. Geological Survey.

But as excited as scientists worldwide are about the rock cores, the cores likely will not help in earthquake prediction. That goal is still out of reach, despite a century of research into earthquake physics.

The cores were pulled earlier this month from two miles (3 kilometers) beneath a seismically active section of the fault halfway between San Francisco and Los Angeles.

Since 2004, a team of geophysicists and seismologists has been drilling atop a creeping segment of the 800-mile (1,287-kilometer) San Andreas Fault. Creeping occurs when two sides of the fault gently slide past each other, triggering small temblors.

Last summer, scientists penetrated an active section of the fault for the first time and began the arduous process of extracting rock samples to the surface.

Scientists next year plan to rig the borehole with sensors to try to catch an earthquake in the making. When completed, it will be the world's first underground earthquake observatory designed to study temblors up close.

The $25 million (17.7 million EUR) project is funded by the National Science Foundation, U.S. Geological Survey and Stanford University.

Comments
World leaders unite with Russia at St. Petersburg International Economic Forum
Blame MH17 on Russia: International investigation turns into demonic circus
World leaders unite with Russia at St. Petersburg International Economic Forum
Skripals fall under heavy British pressure
Russian spy Sergei Skripal recovers from chemical poisoning completely
The Netherlands and Australia officially accuse Russia of downing MH17 over Donbass
Blame MH17 on Russia: International investigation turns into demonic circus
Blame MH17 on Russia: International investigation turns into demonic circus
World leaders unite with Russia at St. Petersburg International Economic Forum
Blame MH17 on Russia: International investigation turns into demonic circus
Blame MH17 on Russia: International investigation turns into demonic circus
Blame MH17 on Russia: International investigation turns into demonic circus
Beautiful and terrifying: Russia shows video of Bulava ICBM underwater salvo launch
London will beg Moscow for forgiveness
London will beg Moscow for forgiveness
Blame MH17 on Russia: International investigation turns into demonic circus
Blame MH17 on Russia: International investigation turns into demonic circus
Blame MH17 on Russia: International investigation turns into demonic circus
Blame MH17 on Russia: International investigation turns into demonic circus
Blame MH17 on Russia: International investigation turns into demonic circus
The Netherlands and Australia officially accuse Russia of downing MH17 over Donbass