Tight gas sands in Whicher Range Field of Perth Basin show large heterogeneity in reservoir cha- racteristics and production behavior related to depositional and diagenetic features. Diagenetic events (compaction and cementation) have severely affected the pore system. In order to investi- gate the petrophysical characteristics, reservoir sandstone facies were correlated with core po- rosity and permeability and their equivalent well log responses to describe hydraulic flow units and electrofacies, respectively. Thus, very tight, tight, and sub-tight sands were differentiated. To reveal the relationship between pore system properties and depositional and diagenetic charac- teristics in each sand type, reservoir rock types were extracted. The identified reservoir rock types are in fact a reflection of internal reservoir heterogeneity related to pore system properties. All reservoir rock types are characterized by a compacted fabric and cemented framework. But distribution and dominance of diagenetic products in each of them depend on primary deposi- tional composition and texture. The results show that reservoir rock typing based on three as- pects of reservoir sandstones (depositional properties, diagenetic features and petrophysical characteristics) is a suitable technique for depiction of reservoir heterogeneity, recognition of re- servoir units and identifying factors controlling reservoir quality of tight sandstones. This me- thodology can be used for the other tight reservoirs.

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