Controls on clay distribution at bed-level in deep-water sandstones; implications for permeability and hydrocarbon drainage

 

PhD Candidate: Arif Hussain

Supervisors: Prof. Peter D.W Haughton & Prof. Patrick Shannon

Funded by: Science Foundation Ireland (SFI), EU and Petroleum infrastructure programme

 

Abstract:

Emerging evidence suggests clays play an important role in modulating turbulence in sediment gravity flows and this can have important implications for the nature of the deposits. Texture and particularly the abundance of detrital clay is often the dominant control on reservoir quality in deep-water sandstones. However clay distribution controls on spatial heterogeneity and accurate quantification of clay abundances still remain significant challenges.

This project is focusing on the details of the clay distribution and clay segregation mechanisms from pore to bed scale, and linking these to sediment gravity flow processes, reservoir quality and petrophysical character. The project will address three broad areas.

(1) Petrographical and XRF profiling of sediment gravity flow deposits including clay-rich bed-types with a pore-scale analysis of the clay morphology, composition and distribution.

(2) Petrophysical analysis of stacked event beds to determine the extent to which different bed types (turbidites, transitional flow deposits and hybrid event beds) can be distinguished on conventional petrophysical logs using state of the art industry software’s.

(3) Reservoir zone level with the investigation of conceptual reservoir models for clay-rich sand distribution and flow modelling to explore drainage efficiency in successions made up of mixtures of different types of event beds.

The study will utilise both industry subsurface and behind-outcrop core datasets.

 

References:

Baas, J.H., Best, J.L., 2002. Turbulence modulation in clay-rich sediment-laden flows and some implications for sediment deposition. J. Sediment. Res. 72 (3), 336-340.

Haughton, P.D.W., Davis, C.E., McCaffrey, W.D., 2009. Hybrid sediment gravity flow deposits-classification, origin and significance.Mar.Pet.Geol.26, 1900-1918.

Pyles, D.R., Straub, K.M., Stammer, G., 2013. Spatial variations in the composition of Turbidites due to hydrodynamic fractionation. Geophysical. Res. Lett. 40, 3919-3923.