Most of Marin County lies between two major faults, the Hayward and the San Andreas. So the Lucas Valley floor is ideal to measure any kind of seismic movement.
For that, geologists are drilling deep -- 760 -feet below the earth's surface.
With the help of drill rods and a powerful drill bit cutting through the rock, workers will spend more a week excavating. Even more interesting is what will go inside, it's a device called a "strainmeter."
"There are compasses in the strainmeter which is a super sensitive device it measures one part per billion. It can detect movement, a centimeter of movement 1,000 miles away," said UNAVCO geologist Andy Tiedeman.
The rock that comes out of a ground is called Franciscan sandstone and it is not soft. It is rich in quartz, making it a hard rock, hard enough to withstand a great amount of strain, therefore ideal for measuring pressure.
"So you build up strain, you get a lot of it, it's like someone giving you a huge bear hug, sooner or later, I don't want to say your bones are going to break, but you just get tight, you can't handle it any more you are like ok enough," said Tiedeman.
Measurements of the buildup of pressure will then be transmitted via satellite to Boulder, Colorado. Researchers from UNAVCO a geological research non-profit will analyze the findings.
Eighty devices will be buried from Vancouver to Southern California. Each of them costs about $300,000.
It's a first for Marin County resident Steve Watry who stops by to see the progress.
"It's our event, it's a California event. It's our hurricane, our tornado. We live with them and deal with them it's always interesting if we could know a little more about them," said Watry.
Knowing more about how pressure builds up may someday help predict the next earthquake.