Shale-gas production in the U.S. is ballooning. I was recently doing a back-of-the-envelope calculation, and I think gas production from shales could easily be north of 5 Bcf per day at present. Here's my thinking: the Barnett shale currently produces 3.5 Bcf a day, according to the Powell Barnett Shale Newsletter. The Antrim made 136.1 Bcf in 2007, according to the state of Michigan. That comes to 370 million a day. The Fayetteville in the Arkoma Basin made 47 Bcf in the first three months of this year, according to the state of Arkansas. That's 530 million a day. I'm less certain about volumes for the Woodford in Oklahoma, but Newfield says it has nearly 200 million per day net, and it's running 12 of the 46 rigs active in the play. So it's probably safe to double its number to get current play-wide rates. When you add in production from Big Sandy in Appalachia, Lewis in the San Juan and New Albany in Indiana and Kentucky, it's easy to get past 5 Bcf a day. That's truly amazing, as IHS Inc. reports that U.S. shale-gas production was 2 Bcf a day in 2005. Now burgeoning plays in Appalachia's Marcellus and Ark-La-Tex's Haynesville shales are on the horizon, and development of shales from the Pierre in the Raton Basin, Baxter in the Greater Green River, and Mancos in the Piceance/Uinta are under way. So shale-gas production is only going to rise. by Peggy Williams, Senior Exploration Editor, Oil and Gas Investor Contact me at