Ashfield Unit 3621-2 – Bowdoin Dome Field, Phillips Co, MT

Ashfield 3621-2 a

Cumulative Production 143,507 MCF

This well is noteworthy in that it was the first shallow gas well in Montana that was completed with multiple frac stages. This payzones in this well lie between 974 and 1058 ft. It was drilled and completed in the summer of 1992.

Hohn was managing field operations for a major operator on several significant multi well drilling programs during the early 1990’s. The completion practice used by all operators during that time was to perforate the thick pay section with groupings of perforations, then pump a single nitrogen foam frac with the hope of achieving limited entry into the different perforated zones. Production logging work conducted by Hohn indicated that the fracs were only treating the top set of perforations and lower zones were taking little if any frac. In other words, much of the lower pay was unstimulated.

A small operator owned this well and asked Hohn to drill and complete it for him. Hohn shared his thoughts on completion design, which in short, was “pump the frac into the pay”. In order to achieve that, each zone needed to be treated separately. The operator agreed with Hohn’s recommendation to complete the well with two separate frac operations, with flowback and cleanup between stages. In 1997, this technique was applied on the Cedar Creek Anticline Eagle gas field and was documented in SPE paper 38374, This technique became the standard well completion design for hundreds of wells drilled during the last 20 years.

The “pump the frac where the pay is” is the foundation principal that has been used in the multiple stage frac stimulations in all of the shale plays like the Bakken.

IHS Energy Scout Ticket report on the well completion for the 3621-2 well API 25-071-22232