Novel seismic strategies for monitoring fluid flow in C02 sequestration experiments and heavy-oil fields

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Canada has the second largest proven oil reserves in the world. Unfortunately these reserves are predominantly composed of tar sands with very high extraction and refining costs. Heavy-oil exploitation leads also in average to three times larger CO2 emissions than lighter oils. Commercial exploitation of these heavy oils in an environmentally friendly and sustainable fashion therefore demands the development of suitable CO2 sequestration strategies in order to reduce the emission of greenhouse gases into the atmosphere. Yet public and political acceptance of CO2 sequestration is unlikely unless we are able to detect fluid migration inside the storage reservoir reliably and most importantly the presence of any CO2 leakage. This proposal outlines new approaches to (1) develop robust, reliable and highly sensitive tools to monitor CO2 fluid migration and detect leakage; (2) examine strategies to reduce CO2 monitoring costs compared with conventional hydrocarbon acquisition and processing requirements; (3) improve detection of heavy-oil liquefaction to reduce steam-to-oil ratios thereby reducing drainage costs and environmental footprints. This will be achieved by integrating information contained in both microseismic recordings and surface seismic data, and by developing novel technologies to differentiate between in-situ variations in pressures and fluid contents. This is relevant since pressure perturbations precede fluid flow. Detection of pressure perturbations can therefore provide timely information on potential fluid flow pathways and leakage spots, well in advance of the actual fluids escaping in CO2 sequestration sites. It can also help to improve reservoir simulation models to enhance heavy-oil drainage. Such fundamental and applied research in both heavy-oil extraction and CO2 sequestration is essential to keep Canada at the forefront of hydrocarbon exploration and exploitation.