WICHITA, Kan. (AP) — A task force appointed by Gov. Sam Brownback to find out why the number of earthquakes in the state has been rising says there isn’t enough data to make a determination.

The Wichita Eagle  reports there were 49 earthquakes between the start of the year and late August, mainly in the south-central part of the state where a practice known as hydraulic fracturing, or fracking, has contributed to a steady rise in gas and oil production.

Many have pointed fingers at fracking, which uses a mixture of sand, water and chemicals under high pressure to release oil and gas from rock, as the cause for the increase in earthquakes.

But task force chairman Rex Buchanan says there’s no baseline against which the recent number of quakes can be compared.