Ann: Operations Update, page-187

https://en.wikipedia.org/wiki/Barnett_Shale

A timely reminder for everyone...

The field was discovered in 1981 when Mitchell Energy drilled and completed the C. W. Slay #1 near Newark, Texas, in Wise County. The well was drilled vertically, completed with a nitrogen foam frac, and did not produce enough gas to cause any excitement.  Despite the low production rate, Mitchell Energy owner George P. Mitchell was convinced that he could find a better way to produce gas from the Barnett. Mitchell persevered for years in the face of low production rates in his initial wells, low gas prices, and low profitability. Industry commentators have written that few, if any, other companies would have continued drilling well after well in the Barnett Shale. Mitchell is widely credited with personally making a success of the Barnett Shale, and thus creating the gas production boom in the Barnett, and, when other companies imitated his techniques, many other shale-gas and tight-oil successes in the US and other countries.