Codell Sandstone oil production trends, Northern Denver Basin, Laramie County, Wyoming
figureposted on 2017-01-01, 00:00 authored by R.N. Toner, E.A. Campbell
The oil-bearing Codell Sandstone was historically deemed uneconomical due to its low porosity and permeability, and its lack of traditional hydrocarbon trap. With recent advances in horizontal drilling and hydraulic fracturing (frac) methods, this unconventional tight sand is now proving to be a highly productive oil reservoir. This study investigates the characteristics of the highest-producing Codell Sandstone wells in Laramie County, Wyoming. Identifying operational best practices can aid industry and regulators in optimizing future oil production from the Codell Sandstone in the northern Denver Basin. The initial, first-months, and cumulative production of all horizontal wells producing from the Codell Sandstone in Laramie County, Wyoming, were compared spatially to isopach and structure contour maps. Production was also cross-plotted against drilling and completion practices utilized in this area, specifically lateral length, lateral orientation, and completion techniques. These spatial and graphical comparisons indicate that while thickness and formation depth do not appear to influence well production, wells with long laterals oriented north-south have consistently superior production than those drilled with shorter lengths and alternate directions. The optimum number of frac stages and amounts of slurry and proppant currently used to complete Codell Sandstone wells are also assessed.