Decrypting Causes of Sand Control Failure and Improving Productivity of Multi Zone Single Trip Gravel Pack

Abstract

Abstract Multi Zone Single Trip Gravel Pack (MZ-STGP) system has been the solution for developing sand prone reservoirs in the Mahakam Delta, Indonesia. Despite providing cost effective solutions, few sand control failures has been recorded. It is deemed necessary to understand the cause of sand control failure and prevent it in the future. Sand control failure may be related to unique design of MZ-STGP or general gravel pack (GP) design. Initial investigation reveals that poor gravel packing quality may be one of sources of sand control failure. Combined with other tools, gamma ray and saturation logging help to assess gravel pack quality. At the same time, they may also be used to detect invasion from fine particles causing drop of productivity. After extensive investigation from logging datas, three main causes of MZ-STGP were identified as bridging and incomplete gravel pack pumping, sand retention problem and low proppant coverage. This paper describes the actions to improve robustness of sand control, as well as the implementation of fines migration additives in order to improve the productivity. To date, a database of GP zones has been created. More than 25 new wells and more than 100 zones were assessed prior put on production to assure no anomaly on gravel pack quality and assuring correct clean up procedure is applied. This contributes to no major sand control failure despite extensive gravel pack operation in Mahakam block.