( CNN ) -- California may be known for its earthquakes , but so far this year it has been surpassed by an unlikely state : Oklahoma . Experts say wastewater wells are likely linked to the big increase in the number of quakes recorded in Oklahoma . Between 1978 and 2008 , Oklahoma experienced an average of just two quakes of 3.0 magnitude of greater . In 2014 , as of Thursday , there have been about 207 such quakes recorded in the state , according to the U.S. Geological Survey . The upward trend started in 2009 , with 20 quakes of 3.0 magnitude or greater , then 43 the following year , and jumping every year with the exception of 2012 . Oklahoma has now surpassed California in quakes , and seismologists see no end in sight , CNN meteorologist Chad Myers said . California has recorded about 140 3.0-magnitude quakes or greater , compared to 207 in Oklahoma . The oil and gas industry 's injection of wastewater deep into the Earth apparently is linked to the shift in seismic activity in Oklahoma , Myers said . The fracturing fluid seems to be lubricating existing faults that have not moved in recent years , he said . The fracturing process is not creating new faults , but are exposing faults that already exist , he said . On Wednesday , at least seven earthquakes were recorded in Oklahoma , according to the USGS . There were no reports of significant damage , but that does n't mean that these quakes are not of concern to scientists . `` The fact that the number of earthquakes in Oklahoma is even comparable to California is unusual , '' USGS geophysicist Rob Williams said . `` We 've seen swarms of earthquakes over the interior of the U.S. , but this is on a completely different scale , for the area where all the earthquakes are occurring is bigger than any previous swarm , '' he added . `` It 's not really a swarm , it 's really a collection of swarms . '' It can not be ruled out that the spike in earthquakes is a once-every-10,000-years thing , but scientists do n't know and a surprised by the numbers . `` Given the rate of earthquakes over the last six months , it 's concerning enough to be worried about a larger , damaging earthquake happening , let alone what might happen in the future , '' Williams said . Many of these quakes are being linked to wastewater injection , he said . Some earthquakes have been linked to hydraulic fracturing , or fracking , but for the most part , the Oklahoma earthquakes are linked to wastewater wells , Williams said . Geophysicists have not been able to gather data to pin down the certain set of wastewater wells that are causing the earthquake problem , but they 're hopeful to learn more about the problematic wells in the future . Research into the links between the wastewater wells and quakes started about four years ago , Williams said . To better gauge the increased quakes , USGS and Oklahoma officials have added monitoring stations , which now stand at 15 permanent facilities and 17 temporary stations . The Oklahoma Independent Petroleum Association last month urged a wait-and-see approach in judging the USGS 's assertions on links between wastewater disposal and earthquakes . `` Because crude oil and natural gas is produced in 70 of Oklahoma 's 77 counties , any seismic activity within the state is likely to occur near oil and natural gas activity . The OIPA and the oil and gas industry as a whole support the continued study of Oklahoma 's increased seismic activity , but a rush to judgment provides no clear understanding of the causes , '' the industry group said . Measuring the magnitude of earthquakes . What to know about earthquakes . The place where two earthquakes hit every hour . Feds : Energy mining 's disposal wells may have role in Oklahoma 's earthquakes . CNN 's Shawn Nottingham and Michael Martinez contributed to this report .
So far this year , there have been more quakes in Oklahoma than California . Experts : Wastewater wells appear linked to many quakes . Scientists worried about a major earthquakes .