Reservoir Monitoring and Dynamic Reservoir Characterization with Production, Seismic, and Electromagnetic Data

Reservoir characterization with only production data and prior information suffers from lack of information. 4-D seismic in addition to production data/prior information has the potential to increase the attainable quality of the property model significan tly. 4-D seismic has become a very useful tool within the industry for qualitative monitoring of fluid movement and localization of trapped oil during production. Many callenges remain, however, especially related to quantitative use of 4-D seismic and ti me-lapse interpretation of multi-component seismic data. Quantitative use of 4-D/4-C seismic is a clear advantage for reservoir monitoring, and a necessity to be useful for reservoir characterization. Tasks 1a, 1b, (see project description) focus on impro ved methodology within this field. Electromagnetic data from Sea Bed Logging (SBL) are in several respects complementary to seismic data, and therefore has the potential to further increase quantitative accuracy both within reservoir monitoring and charac terization. SBL applies very low frequencies, however, so it can potentially be difficult to obtain good resolution from such data. It is therefore important to investigate into the resolution obtainable from 4-D electromagnetic data - alone - and as a su pplement to other data sources such as 4-D seismic. Tasks 2a, 2b, (see project description) focus on important aspects of qualification of time-lapse SBL data for reservoir monitoring and characterization. Inversion of production data is in itself a very challenging task. Novel data types, like 4-D seismicand 4-D electromagnetic data, increases the possibility of obtaining a quality solution, but it also poses some questions as to how formulate the inverse problem in order to utlize different data types o ptimally, and how to deal with uncertainty assessment in this situation. Tasks 3a, 3b, 3c, (see project description) will investigate into such aspects regarding utilization of different data types.