Page 18 - MSc_thesis_R A Kil

1 Introduction

The eastern part of the island of Favignana (eastern Sicily, Italy) presents extensive exposures of a
bioclastic sand wedge complex of exceptional quality. Access to the outcrops is easy because almost all of
them are situated in quarries which have been exploited since hundreds of years. This study presents an
unprecedented three-dimensional insight through a potential hydrocarbon reservoir analogue.

Preliminary research and a quick investigation in the field (A. Moscariello, personal communication)
showed that the eastern Favignana rock type was a promising study area, and it could therefore be useful
as an analogue for existing hydrocarbon producing fields. The study of reservoir analogues can be very
helpful in improving the ultimate recovery and production rates of a comparable oil or gas field. It has
been proved to be a useful method to improve the understanding of the reservoir geometry and flow
behaviour of hydrocarbon producing reservoirs (Bhushan & Hopkinson, 2002). Through the information
extracted from an analogue, 1) well placement; 2) production intervals; 3) water flood strategy; or 4) other
enhanced oil recovery methods can be optimised to a better extent.

Analogues have proven to be a useful comparison with reservoirs because of their exposure at the surface.
One of the challenges in the production of hydrocarbons is to access key information which would unravel
the detailed architecture and internal geometry of the reservoir. Typical reservoirs are situated up to
several kilometres below the surface, and data are is often very detailed but limited to the near-wellbore
area — such as petrophysical data — or in a low resolution and available over a large area — like seismic
surveys. The advantage of studying analogues is that the analysis of reservoir rock can be done on
all scales, from microscopic analysis of small fragments of rocks to depositional environment and its
associated geometries and lateral distribution.

The aim of this study is to 1) describe the sediment facies; 2) reconstruct the internal architecture;
3) determine reservoir properties; and 4) build a facies model of the eastern part of Favignana. This
covers a large amount of data, from millimetre to reservoir scale. A fieldwork campaign during the winter
period was organised. Prior to the start of the project, the deliverables of the research were defined as:

• Stratigraphical and facies logs
• Microscopic description
• Reservoir properties (porosity - permeability)

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