Porosity, Cementation, Diagenesis and Their Influence on the Productive Capability of Sandstone Reservoirs in the Sava Depression (Croatia)

Abstract

The sandstone reservoirs in the Sava depression lost their primaryporosity through compaction and cementation in the carly stage ofdiagenesis. Dissolution events enlarged porosity and created reservoirs that were composed mainly of secondary porosity, but some zones of these reservoirs were destroyed by precipitation of late Ferich calcite and dolomite cement. Three groups of sandstones differing in reservoir quality are identified - highly porous litharenites, litharenits with intermediate porosity, and weakly porous, highly cemented litharenites. The type of porosity depends on the clay content in sandstones, which is the result of water energy and depositional environment.