T - Some where you asked how the EIA distinguishes "tight gas" from "shale gas". Just stumbled into this...the EIA's own words:
"Tight gas became a separate wellhead pricing category when the Natural Gas Policy Act of 1978 was passed and established an incentive to produce tight gas resources when natural gas resources were believed to be scarce. When wellhead natural gas prices were deregulated, tight gas lost its specific market-related definition and now refers to natural gas produced from low-permeability sandstone and carbonate reservoirs."
IOW as I pointed out: such definitions by the EIA bean counters have nothing to do with hz drilling or frac'ng. Their classification is based solely on the nature of the porosity (i.e. fractures in UNCONVENTIONAL reservoirs and low permeability in CONVENTIONAL reservoirs. The NGPA of '78 was a brain fart of the govt to control the normal market dynamics of NG. Led to weird sh*t like the price of NG coming from a RECENTLY drilled well at 15,100' being significantly higher then an older well producing from the same depth or a RECENTLY drilled well at 14,900'. Same pricing game played with a low perm sand drilled recently and from "old" wells. And then there were different pricing rules for interstate production, intrastate production and imported NG.
Eventually the govt couldn't deny how screwed up they made the process and rescinded the rules. But as the above excerpt shows they still hang on to some of the categorization. They still have a problem: "shale gas" can be produced from fractures in a hz well drilled in shale formation. But what do they call production from from fractures in a sandstone formation? BTW that's not uncommon in the Permian Basin. Also understand that they also call NG produced in oil wells in the shales as "tight gas" so that number includes a lot more then just the Marcellus et al.
Also according to the EIA of the 14 tcf from "shale gas and tight oil plays" about 5 tcf comes "tight" reservoirs. But what's truly amazing howcwrong the EIA can be even with very shot term predictions. From 2015:
"As a result of growth in production, domestic production is soon expected to surpass domestic consumption of natural gas, and by 2018 the United States becomes a net exporter of natural gas for the first time since the 1950s. By 2040, net exports of natural gas reach 7.5 Tcf, which is 18% of total U.S. production."
Instead domestic NG production (according to the same EIA) has not increased but appears to have begun a decreasing trend:
https://www.eia.gov/dnav/ng/hist/n9070us2M.htm