South Jenner Horizontal Wells A Water Coning Case Study

Abstract

Drilling AND COMPLETIONS South Jenner horizontal wells a water coning case study W. RANDY FREEBORN, BOYD RUSSELL and ALAISTAIR J. MacDONALD AEC Oil and Gas Company ABSTRACT AEC has been a Canadian pioneer in the use of horizontal well technology to combat the adverse affects of water coning A medium radius well of 420 m horizontal displacement was drilled in July 1987 and has been produced at controlled rates since that time. A follow up tong radius well with a horizontal displacement of 1042 m was drilled in December 1988. These experimental wells are targeted to recover oil from bottom water reservoirs where the net pay is too thin to justify vertical wells. This paper will describe AECs @nence in planning and design-ing its jirst two horizontal wells, and share insights which have been gained in the drilling, completion, operation and reservoir evalua-tion of these wells. Background The Suffield Upper Mannville i pool, commonly known as the South Jenner pool, is located in the northwest comer of the Suffield military range in southern Alberta. Discovered in 1976 by WeSt-coast Petroleum Ltd., the pool was first developed on 16 ha spac-ing for primary production of 14' API heavy oil. With an active aquifer under the oit, water breakthrough was rapid and recovery was in the range of lolo to 201o.In 1981, a five well in situ combustion pilot was initiated as the only EOR technology practical for the reservoir configuration and depth. This pilot operated until 1986. AEC is also presently con-ducting a hot waterflood and testing cychc gas/chemical injection to enhance recovery from the developed portion of the pool. In 1985, AEC decided to improve recovery by matching well spac-ing to drainage area. Using a reservoir simwator, it was detemiined that wells could be as close together as 100 m without reducing the ultimate production from each weD. As a result of this informa-tion, 132 infib wells were drilled in a seven spot orientation on onc hectare spacing. This approach has increased recovery to 25To of the developed oil in place for vertical wells.Horizontal wells are now being used to produce oil from por-tions of the reservoir which cannot be economically developed with vertical wells. A short radius well, AEC WC 51 Suffield EX 6-34-19-8 W4M (5I-34), and a tong radius well, AEC WP I IM Suffield EX 6-3-20-8 W4M (i I M-34) were drilled in July 1987 and December 1988, respectively, to test this technology. Geology and Geophysics The South Jenner oil pool is an Upper Mannvifle Glaucoiitic sand-stone which was deposited in an estaurine environment. The sand is consolidated, but friable, and exhibits an upward coarsening typi-Keywords: Horizontal well, Coning, Long radius, Medium radius. Paper reviewed and accepted for publication by the Editorial May-June 1990, Volume 29, No. 3 cal of an estuarine bar sequence. Subsequent to the sand deposition, the estuary was filled with a silty sandstone which lacks productive capacity. This silt section is thin or absent at the apex of the bar; however, it thickens toward the re...

Loss and restoration of water coning control – field case history and prediction

“…Horizontal wells have been used to produce oil from these offshore heavy oil reservoirs, and many field cases have demonstrated the advantages of the horizontal wells compared to the vertical wells [14][15][16][17][18]. However, horizontal wells also face technical, environmental, and economic challenges in oil-water treatment and water disposal caused by water cresting problem [19][20][21][22][23][24].…”

Effectively optimizing production of horizontal wells in homogeneous oil reservoirs

“…Makinde et al, 2011 numerically studied the performance of a horizontal well after breakthrough of water and further performed sensitivity analysis by setting a base case model and varying reservoir parameters (oil production rate, vertical and horizontal permeability, length of perforation, height above perforation, area extent of reservoir and the porosity of the formation) and production rate independently. Freeborn et al, 1990, undertook a case study of water cresting in South Jenner pool, a thin oil rim reservoir with thick bottom water. Medium and long radii wells of 420 m and 1042 m horizontal displacements respectively were drilled to determine their inflow performances compared to a vertical well in the presence of bottom water.…”

“…In addition, the water cut over time for each well was not reported. (Freeborn et al, 1990) numerically investigated different placement of the horizontal well from the top of the reservoir and observed that there was a decline in oil reserves produced when the well is closer to the OWC and water cresting is more likely to occur faster due to the upward water flood provided by the bottom water. A more comprehensive and general review on cresting can be found in (Makinde et al, 2011, Permadi andJayadi, 2010).…”

“…In this regard, a novel procedure for mimicking inclined or deviated wells was developed for the purpose of this research. This procedure involved varying the inclined section of the horizontal well without altering the lengths of the laterals (having same completion mechanism) and vertical (main bore) sections of the horizontal well unlike in the works of Freeborn et al, 1990. This was possible using compression and pneumatic fittings.…”