Integrated Approach to Monitoring Steam-Induced Geomechanical Deformation Using Microseismicity and Geodetic Datasets
As Petroleum Development Oman (PDO) moves towards the EOR (Enhanced Oil Recovery) phase, many projects have been identified for different EOR methods. Qarn Alam field is currently one of the EOR fields under development using Thermally-Assisted Gas-Oil Gravity Drainage which involves injections steam at the crest of the reservoir and pumping-off water from the aquifer. Given its shallow depth and presence of faults in the overburden, the Qarn Alam steam flood is extensively monitored using a variety of geophysical techniques to optimize operations so that the steam/fluids do not breach the caprock and reach the surface. A set of different surveillance tools were selected to safeguard the caprock integrity using continuous data acquisition and processing of micro-seismic monitoring, geodetic GPS and Interferometric Synthetic aperture Radar InSAR surveillance considered as an ideal tool for monitoring entire field as it can reveal an immense value when it is fully integrated in a diverse contextual environment; this must include temporal records of production and injection data. In this work, we present an integrated approach of the correlation between these diverse datasets to detect anomalies related to reservoir discontinuities or overburden changes such as fault activation or creation; We present a detailed quantitative analysis of the correlation for historical temporal and spatial subsidence/uplift patterns that can be related to fluid production and localized uplift related to steam injection. Furthermore results are integrated with Geomechnical model to understand more on the effects of associated elements on the caprock integrity and to quantify and predict injection performance.
AAPG Datapages/Search and Discovery Article #90327 © 2018 AAPG Middle East Region GTW, Digital Subsurface Transformation, Dubai, UAE, May 7-8, 2018