The 'Holy Grail' for earthquake scientists has been accidentally destroyed. Accidentally on purpose, that is!

And "Holy Grail?" Geologists need to get a life.

Pulled apart so that it no longer aligned, the humble curb wasn’t much to look at. But for earthquake scientists, it was a kind of Holy Grail, perfectly illustrating the seismic forces at work underneath this Bay Area neighborhood.

Since at least the 1970s, scientists have painstakingly photographed the curb as the Hayward fault pushed it farther and farther out of alignment. It was a sharp reminder that someday, a magnitude 7 earthquake would strike directly beneath one of the most heavily populated areas in Northern California, like it did in 1868. 

Then, one early June day, a city crew decided to fix the faulty curb —  pun intended. By doing what cities are supposed to do – fixing streets – the city’s action stunned scientists, who said a wonderful curbside laboratory for studying earthquakes was destroyed.

“They really took it out. Wow,” David Schwartz, a U.S. Geological Survey geologist, said when he clicked on a photo of the curb’s destruction. “It really was an iconic location on the Hayward fault.”

CW here.  No, Dave, they didn't "take it out," they just reset the meter.  You can still measure the movement from this point just as well as before the repair, because you still have the fault right there, and it ain't stopping any time soon.

“We weren’t aware of it,” said Kelly McAdoo, assistant city manager. She said the curb was replaced to install a wheelchair-accessible ramp at that intersection, one of about 150 to 170 such ramps that are installed every year at a cost of $3,000 each. 

“Our mandate from our council is that we have safe sidewalks and accessible sidewalks for all members of our community,” she said."

1971 - Note the position of the curbs and contact between the curb and sidewalk. And note that cool classic car in metallic blue in the background! Want!

In 1979, there was about two centimeters or nearly an inch of creep movement.

2002 - The gap between the curbs has widened.

1974 - A series of tears in the asphalt (en echelon shears) form where the Hayward fault crosses Rose Street at Prospect. Note each shear is to the left of the last one. These are said to be left-stepping.

1984 - The fault crosses under the corner of this house on Hotel Street, bending the wall and
warping the door-frame.

This old fence at
Holy Sepulchre Cemetery in south Hayward
has been offset by fault creep more than 3 feet
since it was built in the nineteenth century.

The fact that the ground is moving likely helps prevent a quake on this fault, as the slow mo creep helps relieve stress.  If it stops....watch out!