More than 230 earthquakes of magnitude 3 or above have occurred in a state since 2014, compared with an average of one a year before 2008
Most continuous earthquakes are a series of aftershocks after a strong earthquake, but this is not the case with earthquakes in the state.
 Frequent seismic activity has raised questions and some researchers have found that since 2014, in order to prevent toxic waste water from drilling and hydraulic fracturing in oil production from polluting surface water, start injecting this waste water into the impervious layers of underground rocks, which is likely to be the key cause of the earthquake