According to several recent technical papers, hydraulic fracturing often misses its target, and productive early wells in stacked plays may be the template for development plans that leave a lot of hydrocarbons stranded.
Shell’s testing shows that nearly half the time when it is fracturing one stage, the fluid actually flowed outside the wellbore to other stages instead. While that work was based on a fracturing design not widely used in shale, known as single entry because it fractures one spot per stage, other diagnostic testing has shown the same problems for widely used plug and perf treatments.
Instead of shooting out through a sliding sleeve and fracturing the reservoir, the fluid flowed between the cement and the rock toward the end of the well, then jumped back into the casing further down the well before flowing out into a fracture.
“To understand well construction problems, no single fracturing diagnostic can answer all the questions,” Ugueto said.
“If we can grasp that, then I could try to affect the way I complete a well, and I could try to affect the way I’m spacing my wells. And if I could touch either of those two things or both together, those really quickly become billion-dollar opportunities for our company in the case of free cash flow,” he said.
If the microbes in the fluids found in one well are found in another nearby in a different formation that could mean they are producing from the same rock.
Samples of produced fluids were taken from 26 wells, with the team observing that some wells landed in one formation produced mainly from the other formation and vice versa.