http://rbth.ru/articles/2010/06/18/unconventional_Gas_warning_russia.html

Even in Europe there is some significant development of unconventional gas on its way. Led by Exxon, a number of the other international oil companies (IOCs) have obtained exploration licences in Hungary, Poland, Sweden, Germany Romania and the UK. Most of the major IOCs have focused on Poland, where there are significant gas shale deposits that appear to have a geology similar to that of the Barnett Shale in Texas, which is now responsible for 7 percent of US gas production. One industry analyst suggests that the Polish shale fields may have a resource base of between 2 and 10 tcm. Even at the conservative end of that estimate, that size of resource base would significantly enhance energy security across the Central and Eastern European member States.