BTU Content mrditbem "..Sections of the Barnett bordering the Ouachita front (regardless of depth) have the highest thermal maturity and, hence, the lowest BTU content of produced gas.." <A HREF="http://www.searchanddiscovery.net/documents/abstracts/southwest/bowker.htm" target="_blank">http://www.searchanddiscovery.net/documents/abstracts/southwest/bowker.htm</A>