Analysis of Reservoir Scale Fracture Sets in Southern Italy's Carbonate Reservoir Analogues, Monte Faito, Sorrento Peninsula (Southern Italy)

Abstract

Abstract Hauterivian-Barremian dolomitized carbonates of the Monte Faito ridge (Sorrento peninsula, Italy) rep-resent a good analogue for the Lower to middle Cretaceous portion of the reservoir units of the Southern Italy oilfields. In order to gain a better understanding of the distribution of reservoir-scale, flow-controlling ‘fracture corridors’ and of the nature of the mechanical boundaries con-trolling their vertical propagation, an integrated sedimentological, petrographic and structural study has been performed on a 200 m-thick succession of alternating dolostones and limestones. The fracture analysis, performed on a 3D model generated from photogrammetry with the help of an Unmanned Aer-ial Vehicle, identified a clear mechanical stratigraphy for large-scale fracture corridors and fault damage zones. The following stratigraphic survey established that the position of the main mechanical interfaces is controlled by: (i) tens of meters-thick bed packages dominated by fine- to medium-grained dolomite abutting a package of thick calcareous or calcareous-dolomitic beds; and (ii) packages of thin laminated dolomitic beds, representing thinning upward cycles deposited during the late highstand of lower order cycles. The rather regular stacking pattern resulting from the superposition of several orders of shallow-ing-upward cyclicity may be used to obtain a predictive tool for fracture distribution and impedance.