As an update to SPE 77464, fourteen recent foam/sand treatments provided even higher production rates than earlier fracs. Propped fracs clearly outperformed N2 breakdowns without proppant.
This study updates SPE paper 77464, which compared 97 nitrogen-foam (with proppant) stimulations versus 120 nitrogen-only completions performed in the 1990's in Pike County, Kentucky. Ninety-three of the 97 foam stimulations are located outside of a relatively high permeability area located in the northwestern portion of the study area. For analysis purposes, these 93 wells have been compared with 14 recent foam stimulations drilled throughout 2002 and the first quarter of 2003.
All wells are owned and operated by Equitable Production Company and are located in Pike County, Kentucky and are completed with two stages in the Devonian Shale and Berea formations. Our results indicate that the latest foam treatments outperform the earlier foam stimulations by a noteworthy percentage. This improved performance is most likely due to high-quality post frac clean-up methods, promptly turning the wells in line, and subsequent expert well maintenance.
There has been no significant change in stimulation design for the new wells when compared with the earlier completions, however the latest stimulations are utilizing a consistent design per well (e.g. ramping from 90Q to 75Q, standard proppant volumes sent downhole, similar pad size etc.), whereas the earlier stimulation designs tended to vary from well to well. In addition, line and annular pressures are similar, and reservoir qualities (e.g. relative permeability, net pay thickness, etc) are analogous between the earlier wells and new completions.
In furtherance of this study, the operator is continuing to pump foam with proppant in wells throughout the study area. The results of this paper are significant for Appalachian Basin operators utilizing nitrogen foam treatments since it quantifies the positive influence of rapid well clean-up and first-class well maintenance. Additional acreage is also being evaluated for use of this stimulation treatment, including evaluation of existing wells for restimulation potential. This is the first paper published to update results over such a large study area.
Author(s): R.J. MacDonald, J.H. Frantz, Jr., Schlumberger; S.T. Schlotterbeck, Equitable Production Company; B. Adams, D. Sikorski, Schlumberger
Paper Number: SPE 84834