Downhole Production Logging for Locating Water Sources in Open Hole Completion Oil Producer Wells

Abstract

The use of open-hole completions in the design of production wells is a particularly appealing choice for oil companies, since it can ensure huge economic advantage compared to conventional cased-hole completions. Nowadays, most operators are looking for more innovative economical well completion design. Swell packer is one of the technology that widely used in open-hole completion strategy with combination of others completion accessories. Coupling the swell packer with open-hole completion application, it makes multiple zonal pressure isolation in the following open-hole completion possible: bare foot condition, predrilled liner, stand-alone screen, open-hole gravel pack or even open-hole fracturing packing. However, few typical implications associated with open-hole completion which complicated further the well integrity and flow performance monitoring. In 2012, 11 oil producer wells were completed in Field X with open-hole completion and installed with stand-alone screen (SAS), swell packers and double valve float shoes. First oil was achieved in April 2012 with all wells initially producing high oil rate and low water cut. However, towards the end of 2013, some of the wells started to show high water production. Production logging (PL) was conducted at Well #1 to evaluate the flow contribution and water source. It was concluded that the water was coming from the bottom of double valve float shoe. Remedial action was taken by setting a plug for water shut-off and the water rate dropped drastically. In 2015, it was decided to replicate the production/well diagnostic analysis in all open-hole completed wells. Similar results were then observed by production log (PL) and consequently, remedial action was taken accordingly. The production log (PL) interpretation, historical production plot and surface well test results were integrated and provide the required information to determine the forward production strategy in these open-hole completed wells. This paper will share multiple case studies where water source diagnostics have been performed in open-hole completions, as well as lessons learnt and best practices throughout this process.

A Review of Chan Plot Application and Recent Advanced Models for Diagnosing Excessive Water Production

“…This improvement extended the diagnosing surveys to the reservoir by identifying flowing zones and detecting undiscovered breaches (Bhagavatula et al, 2015). For instance, PLT could be an efficient tool for investigating well integrity diagnosing, and discovering leaks, rather than production allocation, particularly in open-hole completion (Yaakob, 2017). Additionally, the water flow log has evolved as a viable standalone approach for locating tubing leaks and tracking water flow within and behind casings or tubing (Saxen et al, 2013).…”