02936nmc a2200277 4500 20260521160801.0 260224s2001 xxu ing Inglés Sanz, C.A. 5870 Nilson, G.J. 5871 Acree, J.F. 5872 Pino, M. del 5873 Latin American and Caribbean Petroleum Engineering Conference (7th : 2001 mar. 25-28 : Buenos Aires, Argentina) 5738 First Horizontal Well Opens New Gas Opportunities in the Sierra Chata Field, Neuquén Basin, Argentina SPE 69429 Dallas, Texas Society of Petroleum Engineers 2001 12/09/06 ; 17/07/01 The first horizontal re-entry gas well was successfully drilled and put on line in the Sierra Chata field in the Neuquén basin in Argentina. This article compares the model forecast with the results obtained. The objectives were: (1) to add gas reserves and (2) to incorporate horizontal technology that will allow access thin or low permeability sands, in remote areas that would be economically marginal with vertical wells. Recent interpretation of 3-D seismic and geologic data indicated that the "D" Sands were better developed to the northwest of the vertical well SCh-17. In order to access gas reserves postulated to exist there, it was planned to drill a horizontal re-entry well utilizing the existing vertical well, SCh-17 as a re-entry conduit. From the well SCh-17 a re-entry was made at 244 m from the deviation point (KOP) in 1600 m MD, drilling slightly up-dip to 2975 m MD, using with a downhole motor and a MWD logging system. Shale-silt lithologies within the sand members affect the vertical transmissibility (TZ) between the "D" Sand members. Sensitivity runs were made using a reservoir simulator built to test the effect of such variables on the horizontal well productivity. For the most probable case, an initial flowrate of 17.7 MMscfd (502 Mm3/d) was predicted. A final cumulative production of 7.3 BSCF (206.7 MMm3) of gas was predicted by the numerical simulation model. Six months of production history confirmed the forecast and assumptions made in the well proposal and also encourage new horizontal prospects. This year, two additional horizontal wells have been proposed to be drilled in the Sierra Chata field applying some of the concepts proven by the subject well. At least one of which will include an additional deviation of the horizontal wellbore to intersect multiple target zones. Nilson, G.J. 5871 Acree, J.F. 5872 Pino, M. del 5873 Latin American and Caribbean Petroleum Engineering Conference (7th : 2001 mar. 25-28 : Buenos Aires, Argentina) Sanz, C.A. 5870 https://biblioteca.iapg.org.ar/ArchivosAdjuntos/LACPEC2001/Spe69429.pdf CONGTP ddc 130876 130876 0 0 0 0 201798 BVIAPG BVIAPG 2026-03-03 200002920 0 200002920 2026-03-03 01:41:01 2026-03-03 ARCHIVO