[Wonder Warthog]

"While that statement is likely true in being capable of stretching far enough to cover that distance, I believe the typical horizontal well is normally only going to reach 1/2 mile to 1.5 miles, maybe 2 miles."

I was thinking more in terms of being able to go north/south/east/west from a single insertion point. Two miles in all those directions is covering a LOT more volume than two miles straight down. I suspect, as usual, that there are a spectrum of possibilities, some already exploited and some not yet so.

You need to take a peek at the report posted by SC_Pete. The economic numbers are staggering. Texas will be adding 100 BILLION dollars a year to its economy by 2035 due to "unconventional" oil and gas (if I'm reading that table right).

[thackney]

In the GIS info I see for the Bakken and Haynesville shale, I only see horizontal reaching in a single direction.

http://sonris-www.dnr.state.la.us/gis/agsweb/IE/JSViewer/index.html?TemplateID=341

https://www.dmr.nd.gov/OaGIMS/viewer.htm