ABSTRACT
Drilling in the Barnett shale started in the early 1980s, but it took over 20 years and technology advancements, as well as a conducive fiscal, regulatory, and infrastructure environment, to bring about the shale gas revolution. Early shale gas wells in the Barnett were mostly vertical. Verticals were drilled to collect data along with some horizontal appraisal wells to test hydraulic fracturing and mechanical well completion designs. These wells were also used to obtain estimates of initial production potential of the designs. It was not until 2003 that there was a total shift to horizontal wells for developing shale in the Barnett as well as all the other US shale basins that followed.
