Gone...but not forgotten! No, we don't mean the Quad.

Benchmarks are usually bronze disks cemented into the ground. Thousands have been placed across California’s faults. Using these benchmarks, geologists are able to measure the subtle changes in the Earth’s surface that cause movement across the fault zone.

There used to be a gravity benchmark on the Quad walkway, the one going from Shields to the Memorial Union. It was one of the primary sites in the California Gravity Network and part of the National Gravity Network. The gravity benchmark marked a position at which the Earth's gravity had been carefully measured and recorded. Geologists were able to use this site to calibrate their insturments. During construction on the Quad, workers removed the marker which was clearly marked with warnings of stiff monetary fines and possible imprisonment. D’oh!