It wasn’t so much the fracing as the directional and horizontal drilling.
Hydraulic fracturing hasn’t seen many changes over the years and when I say years I’m talking multiple decades. Drilling is where the change has been made and as you pointed out it’s the directional drilling that’s led to the boom. A vertical well spends little time in the actual oil bearing sands/shale, that zone can be as small as 60 ft or in some cases larger. The horizontal doesn’t just pass through the zone as a vertical does but runs horizontal through the zone, some well over a mile. On the vertical we’re lucky if we can perforate and frac two areas. With the vertical we can frac numerous times in the same zone. We’re seeing thirty and sixty stage fracing in some wells which opens up five hundred to one thousand times more area than possible with a vertical well. The only change with the fracing is the number of frac’s per well. This leads to another big change in where the fracturing of a well may ten times as much as the actual drilling costs. with a vertical well the average cost of fracing ran about one third of the drilling cost. This explains the high demand for fresh water and sand that horizontal wells require. My normal tank battery setup for a vertical well is two five hundred barrel oil tanks and a five hundred barrel water tank. Standard set up for a horizontal can be four to six one thousand barrel tanks and two thousand barrel water tanks. Larger separators and heater treater’s are also use and some times staged themselves to accommodate the increased production. It’s a whole new world for us older guys.