The seismologists demonstrated the early warning system on a monitor in San Francisco on Tuesday. The system is similar to the one that gave Japan precious seconds before last month's deadly earthquake and tsunami.
"That is very much like what Japan has today. We feel that the U.S. deserves a similar kind of system to what Japan already has," said UC Berkeley seismologist Richard Allen.
The estimated cost is $20 million a year for many years to build a network of earthquake sensors, transmitters and receivers.
They say the cost is worth it, and that even a 30-second warning could save lives.
Doug Given of the U.S. Geological Survey said he hoped it did not take a killer quake to spur action on a system.
The system works by detecting weaker waves, known as primary waves, which travel faster and can be measured earlier than the more powerful secondary waves.
The Associated Press contributed to this report.