The Earth Institute at Columbia University offers a list of its scientists (updated March 5, 2013) with "a wide range of expertise to journalists covering natural-gas production using hydraulic fracturing (hydrofracking). This includes basics of energy exploration and extraction; rock mechanics; contaminants in underground water; manmade earthquakes; and economic/political questions surrounding the practice."

http://blogs.ei.columbia.edu/2011/08/15/hydraulic-fracturing-resources-for-journalists/