Injected and remobilized Eocene sandstones from the Alba Field, UKCS: core and wireline log characteristics

Depositional and remobilized sandstone units are identified in core from the Eocene sand-rich deep-water Nauchlan Member and termed stratified and unstratified facies, respectively. The unstratified facies association records an increased intensity of sand remobilization, and inferred fluidization, upward. Unstratified facies have lower average porosity and permeability than stratified facies. Bulk density and acoustic velocity are higher in unstratified facies than in stratified facies. The general geometric relations of the reservoir can be inferred from a correct identification of the facies. Correlation of borehole data with (3D PS) seismic data enables the seismic to be used as a lithology indicator. A modified interpretation of sandbody geometry is made that incorporates sand injection features and provides a more accurate reservoir model.