Laboratory Compaction of Synthetic and Reconstituted Mixtures: Implications for Rock Physics Properties of Siliciclastic Fine-Grained Sediments
Event name: 81st EAGE Conference and Exhibition 2019
Session: Seismic Interpretation - Rock Physics II
Publication date: 03 June 2019
Info: Extended abstract, PDF ( 5.55Mb )
Price: € 20
Muds and mudstones are the most common sediments around the world. They have the primary control on fluid flow in sedimentary basins and near-surface environments. The fine-grained sediments are of key importance in CCS, waste repositories, petroleum exploration, and increasingly more in production. This study presents mechanical compaction of brine-saturated reconstituted borehole cuttings and synthetic quartz-clay mixtures to investigate the evolution of properties in fine-grained clastic sediments during burial. The primary research question was whether rock physics and hydraulic properties could be described and constrained by binary quartz-clay mixtures. The synthetic binary mixtures were prepared by mixing quartz with non-swelling (kaolinite) and strongly-swelling (smectite) clays, which can represent the endmember properties within the clay minerals. A well-constrained porosity-permeability bound is defined, where the compaction trends of pure quartz and quartz-smectite mixtures describe the maximum and minimum boundaries, respectively. The quartz-clay mixtures, however, fail to provide bounds to constrain the broad range of variations in physical and seismic properties of reconstituted aggregates, and consequently natural mudstones. The well log analysis shows a broad range of variation in properties of studied caprock sequences. The results indicate the importance of incorporating micro-scale properties into the geological and geophysical interpretations through rock physics understanding.