Joint Elastic-Electrical Properties of Reservoir Sandstones

Over the last decade, marine controlled source electromagnetic (CSEM), sub-seabed imaging has developed to a state where routine resistivity mapping of hydrocarbon reservoirs is now possible. Co-located marine seismic and electrical resistivity survey data could provide the engineering parameters needed to better assess the economic potential of hydrocarbon reservoirs without the need for drilling, and could provide additional reservoir monitoring capabilities in the future. However, proper exploitation of joint seismic-CSEM datasets will require a much better understanding of the inter-relationships among geophysical (elastic and electrical) and reservoir engineering properties. <br/><br/>This project seeks to study the inter-relationships among the elastic and electrical properties of typical reservoir sandstones for improved insight into wave propagation phenomena in porous rocks. <br/><br/>A high quality joint elastic-electrical dataset has been collected on a set of 67 sandstone samples showing a range of porosities, permeabilities and clay contents. The measurements were simultaneously carried out at differential pressures up to 60 MPa. Elastic properties (compressional and shear wave velocity and attenuation) were measured using a pulse-echo technique; electrical resistivity was recorded at AC frequency of 2 Hz using a circumference resistivity measurement method. The effects of porosity, permeability, clay content and differential pressure on the low frequency (2 Hz) electrical resistivity properties and the influence of differential pressure and petrophysical parameters on the joint elastic-electrical properties of reservoir sandstones were analyzed. A three-phase (quartz, brine and pore-filling clay) effective medium model based on self-consistent approximation (SCA) and differential effective medium (DEM) for the joint elastic-electrical properties of reservoir sandstones was developed and was found to give a good description of the experimental observations.

Name dc:type.qualificationname

Ph.D.

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

University of Southampton

Year dc:date.issued

2010

Author dc:creator

• Han, Tongcheng

Advisors dc:contributor.advisor

• Best, Angus
• MacGregor, Lucy
• Minshull, Timothy A.
• Marshall, John