Why matrix porosity is important in fracture carbonate reservoirs.
Fracture reservoirs with minimal effective matrix porosity tend to form in deep water carbonates such as the late Cretaceous Shiranish Formation in the Middle East and Cretaceous basinal carbonates in the Sureste Basin in Mexico.
Fractured reservoirs with dual porosity systems tend to form in shallow water carbonate systems such as the Asmari that have matrix porosity controlled by depositional and early diagenetic processes.
Understanding the controls and distribution of fractures is not enough because the structural and facies trends may not always coincide. Reservoir type and behaviour often change as the structure crosses facies belts leading to a reservoir in which the macropore system is controlled by tectonics while the matrix pore system is controlled by the depositional and sequence stratigraphic factors.
If you would like to know more about fractured carbonate reservoirs or our palaeogeographical maps, then please email: pete@cambridgecarbonates.co.uk.
