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The intense swarm of earthquakes that began January 6, 1983, in the Long Valley region of eastern California continues to abate. The rate of earthquakes of magnitude 1 or greater (Richter scale) fell to 24 per day by February 8, compared to 100 per day in late January and 1000 tremblers recorded on January 7. Prior to the current swarm, the average daily number of magnitude 1 or greater quakes was 8–10. The area has experienced more than eight seismic swarms since the four magnitude 5.6–6.1 earthquakes of May 25–27, 1980, that occurred in the southern part of the Long Valley caldera. Early ground deformation measurements indicate limited movement of magma deep within the earth.