The drilling of development wells in layered sand-shale sequence involves thin and sinuous targets. Optimal well placement is a requirement for these thin reservoirs in order to drain them in a cost effective manner. A slanted well with 84 deg inclination was planned and drilled to drain oil from the Lower Cretaceous layered sands of target formation as part of a development plan to increase the production rate from the North Kuwait oil field which is aligned to Kuwait Oil Company's (KOC) goal of producing 4 million bbl/d oil by 2020 and sustained it until 2030.
Plan is to build the inclination through the 12 ″ hole section kicking off with Motorized Rotary steerable system up to 54 deg inclination. The 8 ″ section is planned to build from 54 deg to 84 deg and again planned to be drilled with rotary steerable system and neutron, porosity technologies to allow precise landing with high angle in the required zone of interest. The 6 1/8″ section is planned to be drilled with Rotary steerable and triple combo Logging While Drilling (LWD) technologies to precisely drill through the required zone of interest. The well was planned to be drilled with Rotary steerable tools to enable smooth well profile and avoid micro doglegs to enable smooth deployment of ICD completions through difeerent layers - sand - shale - silt - shale sequences.
After drilling the top hole curve sections, well was successfully landed into the target sand channel and drilled through the drain hole section using resistivity, gamma ray and density neutron tools. Well was monitored in real time with a multi task team comprising drilling department, field development, well placement and target depth was called out while it approached the expected zones with water fingering. After the completion of the 6 1/8″ reservoir section, achieving very smooth profile with pre - selected technologies, a dedicated cleanout run was performed to make sure that the hole profile is more precise and smoother for the deployment of ICD completions for the first time in a high angle deviated well crossing through different layers. After taking all the precautions related to hole cleaning, mud weight management to mitigate the shale sections open at high angles and well geometry, well was completed with ICD completions for the first time in Kuwait for a slanted 84 deg well within sand-shale sequence.