Innovative Real-Time Well Monitoring and Integration of Multiple Data Sources for Reducing the Uncertainty and Informed Decision Making

Abstract

Kuwait Oil Company is currently developing subsalt deep fractured carbonate reservoirs of Toarcian age in the northern part of Kuwait. The operational area in northern part of Kuwait encompasses approximately 1800 sq.km covering eight oil & gas fields. These deep HP/HT Toarcian age naturally fractured carbonate reservoirs are overlain by highly over pressured (up to 21 ppg mud weight equivalent) Kimmeridgian - Tithonian age Hith-Gotnia evaporite formations (Anhydrite + Salt alternations). This overlying interval poses severe challenges during drilling and imposes a number of constraints in the well design. Critical log data acquisition in the reservoir section, in some cases, is adversely impacted due these overburden section drilling challenges and challenges in the reservoir section drilling such as differential sticking tendency. On a few occasions, these drilling challenges led to loss of valuable reservoir information. As part of mitigation of the well placement challenges, an innovative approach is adopted comprising tight integration of real time geochemical, drilling data and MWD log data (GR and Resistivity). Further, dynamic pore pressure prediction during drilling reservoir section has been adopted. These measures have resulted in 100% placement in the target reservoir. The formation evaluation results are augmented through integrating core samples, real-time geochemical (XRD/XRF, Pyrolysis) data and RCAL analysis. In this paper, we demonstrate the value of close and real-time sub-surface data integration in the entire value chain of drilling, well placement, log evaluation and well testing. We are also presenting how successfully we have done the fluid characterization using real-time advance gas analysis, which was calibrated with offset wells PVT data. This step has resulted in the identification of potential sweet spots in reservoir section during the course of drilling which was further confirmed through subsequent log data evaluation. These measured assisted in taking optimal perforation strategy.

AAPG Datapages/Search and Discovery Article #90332 © 2018 AAPG International Conference and Exhibition, Cape Town, South Africa, November 4-11, 2018