Precariously balanced rocks, or PBRs as they’re known in geological circles, are ancient and delicately poised natural formations that can offer scientists interesting clues about earthquake ...

These ‘precariously balanced rocks,’ known as PBR’s (no relation to the beer) have been balanced for 10,000 years, a span of time during which there have been 50-100 large earthquakes in the ...

James Brune and his son, Richard, who designs electronic doors for aircraft hangars and fire stations, have spent 25 years mapping precariously balanced rocks in California and Nevada.

Precariously balanced rocks provide clues for unearthing underground fault connections San Jacinto, San Andreas interaction weakens earthquake shaking near them Date: August 4, 2015 Source ...

Scientists gauge the fragility of these rocks by studying their geometry and conducting field tests such as tilt analyses, in which they put a pulley on a precariously balanced boulder and ...

Approximately 80 miles south of Reno, just inside California’s eastern border with Nevada, three distinct, large rocks sit at the edges of cliffs, looking like they will topple over at any moment.

Ancient formations of precariously balanced rocks can provide insight into the rates of rare large-magnitude earthquakes, scientists have said. Formations of precariously balanced rocks (also ...

A precariously balanced rock at Westfield, Vermont. USGS seismologist Thomas Pratt stands on top. The 2-meter measuring stick is provided for scale. Five boulders, delivered by glacier and ...

Such claims about so-called "precariously balanced rocks" (PBRs) are not new, though. Various social media accounts and several online portals have discussed different aspects of the Kummakivi rock.

They look like you could blow them over with a sneeze. Across the world, thousands of "precariously balanced rocks" are perched in strange positions, poised to topple. Once they would have been ...