
%0 Journal Article
%A Fish, R.M. 
%A Zajdlewicz, D.J. 
%T OPTIMAL THIN OIL COLUMN MANAGEMENT&#x2014;THE BREAM STORY
%J The APPEA Journal
%D 2004/06/30
%V 44
%N 1
%P 497-512
%K 
%R https://doi.org/10.1071/AJ03020
%U https://www.publish.csiro.au/paper/AJ03020 
%X Originally developed in 1987 for oil, the Bream N-1 reservoir is a Gippsland Basin Top-of-Latrobe oil and gas accumulation. The original oil column thickness varied due to local structure with most of it 13.5 m and with nearly all of it overlain by a large gas cap. The original depletion plan called for maximising oil recovery through a combination drive and included a provision for returning all produced gas to the reservoir. By 2000 this scheme had proven successful with a 60% oil recovery. The remaining life of the oil resource was, however, limited and a study of the optimum time to initiate gas withdrawals was undertaken.Gas blow-down studies often employ full-field reservoir simulations. This stratigraphically complex reservoir is not suited to full-field modelling due to the interplay of a coning dominated thin oil column with a thinly bedded dipping reservoir. Consequently a different, more efficient tack was taken.key unswept oil areas were identified and studied for their response to a moving oil column, either through mechanistic simulations or analytically. This study with subsequent revisions concluded that gas export would increase Bream&#x2019;s oil recovery by as much as 9.6 MMSTB (1.5 GL) through an active campaign of chasing the moving oil column and/or accessing it at local structural traps.Gas export started in December 2002 after the construction of a new pipeline. Wellbore preparations were initiated in 2001 with the re-activation of previously depleted wells and the re-completion upward of existing wells. These activities have proven successful with Bream cumulative oil recovery now at 66% and oil rates higher than they have been since 1999. 
