The Ridgecrest Earthquake Split Open The Desert And We Went To Look At The Crack

A 6.4 magnitude quake near Ridgecrest Thursday, July 4 caused a crack to open up in the desert, crossing Highway 178 near Trona Road. (Emily Guerin/LAist)

The 6.4 magnitude earthquake that rocked the Mojave Desert on the Fourth of July also created a bit of a tourist attraction: a notable crack through the desert and across a highway.


UPDATE: 7.1 Magnitude Earthquake Strikes Tonight In Same Area As Fourth Of July Quake


On Friday morning, residents from Ridgecrest, along with regional news media, drove about nine miles east of the town to get a look at it. Some people were even taking selfies with the crack.

Caltrans crews had repaired several other cracks on Highway 178, but at least one remained open Friday morning.

It was a couple inches wide on the asphalt, but off-road into the dirt is where it became wider and more visible.

LAist/KPCC reporter Emily Guerin visited the scene Friday morning and performed this unscientific but fun test to measure the depth of the crack.

KPCC/LAist reporter Emily Guerin reaches down into the quake crack for an unofficial depth reading. (Emily Guerin/LAist)

According to our intrepid reporter, she felt some sand at the end of her reach down the crack, though it's unclear just how deep it goes (a longer arm might have helped, she admitted).

So, no, it's not a deep chasm that will swallow you up. And it's nowhere close to the roadway damage Alaska had to deal with after a 7.0 magnitude quake struck in December. But it is a reminder of the power of earthquakes, and how woefully unprepared most of us are for when the actual Big One hits.

Reactions from Ridgecrest residents ranged from fun to horrifying.

For Paul Mayberry, it was the latter. After the quake, which struck just after 10:30 a.m. Thursday, he and his wife ran outside and stood on the street talking to their neighbors.

"It's alive. You're feeling it, You're hearing it — it's not just a little rattle," he said. "The earth is living underneath you. It's moving. You can feel it right through your shoes and you can hear it. It's a deep deep rumble and it keeps coming at you like a freight train from a distance away."

"This was pure horror," Mayberry added. "We're right on top of it. We got trash cans where we're putting our vases and our glassware, heirlooms, just throwing them away."

The quake had been followed by 1,400 aftershocks and counting as of Friday afternoon, with 17 of those at magnitude 4 or higher, according to scientists from Caltech and U.S. Geological Survey. One of the bigger aftershocks was Friday's 5.4 magnitude wake-up call, which hit just after 4 a.m.

But as the days go by, the aftershocks tend to be fewer. The chance that we might get a new earthquake that is bigger than Thursday's magnitude-6.4 has fallen to 6 percent.

WHAT ELSE WAS DAMAGED?

Much of the fault rupture is on the grounds of the China Lake Naval Weapons Base. There is some damage to their air control tower, and possibly other parts of the base, according to USGS seismologist Susan Hough.

The naval base was built during World War II, and so was the housing in nearby Ridgecrest, and that's the good news. It means it was built with somewhat modern earthquake safety codes.

So while we've seen a few structure fires there due to broken gas lines, personal items rattled from shelves or mobile homes jolted off their foundations, the majority of housing in Ridgecrest got through this earthquake without too much damage.

SO WHAT DID WE LEARN?

Hough said she was most jazzed about having that open scar in the desert — the fault rupture — to study. This one is in an L-shaped pattern from two different intersecting faults that moved during the earthquake.

They already have sensors in the ground that can describe when and how they moved. So they will study them to see if they moved at the same time or if perhaps one fault triggered the other.

Next, they will look at the fault many different ways, through GPS coordinates; LIDAR, which uses light in the form of a pulsed laser to measure things in the earth; and INSAR, which maps ground deformation using radar images of the Earth's surface that are collected from orbiting satellites.

So, having the open faults right there will aid their scientific learning about earthquakes. A silver lining, if you will, right there in the dirt.

UPDATES:

6:08 p.m.: This article was updated with new information on the damages and on how scientists will use the crack to learn more about earthquakes.

Emily Guerin, Sharon McNary and Ryan Fonseca contributed to this story.