Outcrop characterisation of turbidite reservoir analogues deformed by fluidisation - Implications for reservoir models

The study of post-depositional sand remobilisation and injection processes has become increasingly important in the oil and gas industry because of the considerable impact on reservoirs quality. Nevertheless, the effect of remobilisation of large volume of sand through fluidisation processes on turbidite reservoirs is still poorly understood. This creates significant issues for reservoir modelling, reserve estimation, well planning and drilling. Outcrop analogues provide essential inputs for the reservoirs modelling by constraining the geometry and petrophysical properties of modified sandbodies. The Panoche Giant Injection Complex (PGIC., Panoche-Tumey Hills, California, USA) is the largest injection complex yet documented from outcrop. This injection complex covers an extended outcrop area and crosscut about 1200 m of slope mud-rich succession with a complex system of dykes and sills. The injections are sourced from isolated slope channels, channel complexes and lobes which provide exceptionally well exposed analogues for turbidite reservoirs modified by fluidisation and injection. We describe such modifications in terms of external geometries, internal architecture and facies distribution and provide examples of how these modifications affect the reservoir properties and the distribution of porosity and permeability.