Cnpyr,gh! 19%S *,ety of Petroleum Engineers, Inc lhs pavr was prepared for pres.entat$on qt the Western Regmnal Meebng held m Anchoqe, Alaska, 22.24 May 1S93 Th IS paper was selected for p!esentauon by an SPE Pmgfam Grnmmea followng rewew of rd'mn'abcm conti, ned m an abstract subm!tted by UIe author(s). Contents of lhe pape, haw not bee n rv,ewed by the scciety of Petroleum Engww.m and are subject to axrecbon by the ati$ The mater! al, as pfesentec!, dces not necessarily feted any position of the s.xwty cd Peud.wm Engineers IM off!cers, w membem Papms presented qt SPE meetmgs are $ubjecl ti Fub4cakm r-by Eddooal C#nmtttees of the So@sty M Petmkum EngmeeIs Pemmsstcm m WY IS restf!cled~an absuaa Of not more ti=n 300 wxds. Illustrations may noI be coPIed The absbacl should conhn Conspicuous acknmvledgment cd tire and by wtmm the paper IS presented Wr!le L!brarmn, SPE, P O Box .S33.S3!3, Richardson, TX 75083.%3.9,
AbstractThe SIIOIIOIV Oil Zone (SOZ) reserwoir within the Nmud Petroleum I&me #1, Elk Hills field occurs at depths ranging from z joo'" to 4500'. ,4 significant portion of the SOZ reservoir was dewloped on 20 acre spacing in the mid 1940's to early 1950's. Three wells were usually completed with 7" combination casing strings (i. e , slot[cd 7" pipe on boltom with cemented 7" pipe above). Follo\ving Resewe open-up in 1975, 10 acre development and infill drilling was reinitiated throughout the SOZ. Wells were drilled to TD, logged, and 7" casing was cemented to [he top of the pay. The pay was opened 10 13" and the~vells \vere completed with 5 %" gravel packed, slotted liners.Well surveillance and production monitoring in the early 1990's revealed that the 1970s gravel pack completions were, in general, producing at lower rates than offset non-gravel packed wells. Efforts to stimulate production from these wells utilizing comentiorml [echrriques such as acidizing, chemical soaks, jet washing, and kniting/scraping proved only marginally successful. As a result, a liner repIacemen( program was developed whereby e~i sting slotted liners and gravel packs were removed and replaced \vi(h non-gravel pocked slotted liners.A live-well pilo[ program was initia[ed in August 1992 to assess the txonomic feasibility of liner replacements in the SOZ This pl-ogrmn incorporated traditional recovery techniques utihz]ng a spear, bumper-sub, Jars and accelerator.Four of the jobs rcqu]red the liner to be mechanically cut and rccoved in sec[ions based on free point survey results.Resul[s of the pilot progrsm proved very encouraging \vith to[al production increasing horn 15 BOPD to 436 BOPD at a cost of $594,000. Costs were significantly higher than anticipated due to the additional rig time and rental tools associated with fishing operations.Recovered liners were found to be almost completely covered with organic (asphaltenes) and formation material. This supplied physical evidence confmning that fines invasion of (he gravel pack coupled with organic deposition severely reduced gravel pack permeability and effec[ive]y plugged the ...
