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Mile for mile, there are almost as many earthquakes rattling Oklahoma as California this year. This major increase in seismic shaking led to a rare earthquake warning today (May 5) from the U.S. Geological Survey and the Oklahoma Geological Survey. In a joint statement, the agencies said the risk of a damaging earthquake — one larger than magnitude 5.0 — has significantly increased in central Oklahoma.

The URL shows the swarm of small earthquakes in Oklahoma. I have not heard any explanation for these. The URL lists all 2.5+ earthquakes in the past 30 days. There is one just across the border in Kansas... According to USGS, there are 123 Earthquakes in the past 30 days in the Oklahoma area. These are all very small earthquakes or better termed tremors.