Success Story of Integrated Reservoir Characterization and Reservoir Management Approach to Deliver Infill Wells in the MTJDA Area, North Malay Basin

Abstract

In the event of high gas demand, infill well drilling is one of the best option to increase gas deliverability. Finding infill well opportunity in a brown field is a challenging task. Reservoir continuity, heterogeneity of the rock properties, pressure depletion and identifying undrained area are the major concern for infill wells candidate selection. A robust reservoir characterization and dynamic information are essential to provide some key understanding about the field. The area of interest, Muda field, is located in the Block B-17 of Malaysia-Thailand Joint Development Area (MTJDA) which has been producing for more than 5 years. Integration of multidisciplinary data is very important to identify the potential hydrocarbon bypassed area. To start with, the geological model was built and constrained with seismic attributes after calibration to the well data. The high uncertainty of reservoir presence in the model was assessed by combining the sand distribution and porosity variation. Subsequently, history matching was performed to calibrate the model with actual production flow rates and reservoir pressure. A reasonably good history match was achieved and provides a certain degree of confidence in production forecast. As a result, it shows some potential undrained areas to be selected as the area of infill well candidate. The infill wells were drilled within 1 to 2 years later and the well results has demonstrated a successful delivery of infill well as expected both in encountered netpay and production. This paper discusses a successful collaboration between multidisciplinary team members in the subsurface division to deliver infill well candidate by building a comprehensive reservoir model which integrate of all hard data from geological concept, seismic attribute, well and production. Five successful infill wells were drilled in accordance to this campaign, expected potential and volume are generally as expected with some surprises in some interval. The gas potential comes from these infills are very important to fulfil gas deliverability. It is foreseen that additional infill wells are expected and evaluated using the 3D reservoir model.