Abstract
Unconventional oil production started in the Bakken formation of North Dakota in 1953. For the first fifty years, the rate of drilling was slow and measured with the scope of activity driven by delineation development associated with naturally fractured structural features and higher permeability formation facies at the edges of the basin. Production got a boost with the advent of horizontal drilling in 1987. However, it was not until twenty years later with the advent of multi-stage hydraulic fracturing of the horizontal lateral that completion and stimulation design advanced to a level which allowed economic development across the whole basin – regardless of structure or existence of a high permeability "sweet spot" facies.
Through 2022, a total of 18,833 wells have been drilled and completed in the Bakken Petroleum System across the United States portion of the Williston Basin. Comparing geologic data, completions parameters and state-reported production results it is possible to understand the fundamental well completion and stimulation changes that have guided industry to develop economic well results over the past seventy years of development. These well completion and stimulation advances have provided industry the opportunity to move from core geologic "Tier 1" areas of the basin to what is referred to as "Tier 2" and "Tier 3" areas which are characterized by an absence of structurally induced natural fracturing or higher permeability geologic facies. In addition, recent drilling and completions optimization has allowed industry to economically develop lower pore pressure and higher water cuts areas that are geographically located away from the highest pressure, deepest part of the basin.
These completion advances have allowed the region to compete on a global scale with production that peaked at 1.49 Million bopd and has now stabilized at ~1.1 Million bopd.
