Hannah proposed that high conductivity fractures may prevent, or at least delay the formation of CaCO3 scale by reducing the pressure drop in the wellbore area.
This paper details a successful fracturing of a high permeability oil well at Prudhoe Bay, Alaska. The treatment was complicated by the zone’s proximity to water, poor leak-off control and the need for a large quantity of proppant.
A calibration treatment was performed prior to the proppant-laden treatment to verify the leak-off coefficient and to determine height growth tendencies. This treatment indicated a grossly higher fluid loss rate than the pre-job estimate and a more conservative treatment was designed. Temperature/gamma logs indicated the redesigned treatment would not propagate to the water zone.
The treatment was pumped successfully and the well cleaned up and responded to the treatment with a productivity increase of 1.33 out of a theoretical maximum of 1.6. This is considered good for a fracture of such modest dimensions.
Author(s): R.R. Hannah, Sohio Petroleum Co.; E.J. Walker, Sohio Alaska Petroleum Co.
Paper Number: SPE 14372