The focus on exploiting natural gas resources has been increased in the recent years since it was characterized as the transitional fuel to a net-zero era. Consequently, a reevaluation of the gas resources under a new perspective seems to be logical. Within this context, the gas-bearing Miocene sediments of the Messara basin in Crete (Greece) are discussed in this paper. The gas shows have been first reported during the 1990’s, without being thoroughly evaluated. This paper presents the interpretation of eight legacy onshore seismic reflection lines, which led to the construction of the 3D subsurface structural model of the Neogene Messara basin. The seismic data reveals the basin depocenter which accommodates approximately 1500 m of the Miocene sediments. The relationship of the Miocene deposits with the existence of shallow gas is also examined and discussed. New organic geochemical results combined with the published geochemical data are used to discuss the gas generation potential of the Miocene sediments. The porosity and permeability measurements on surface samples are also presented to describe the reservoir characteristics. The integration of the data mentioned above suggests that the Miocene sediments of the Messara basin comprise intervals with adequate organic matter to generate the observed gasses and good reservoir sandstones to accumulate the generated gas. The gas might have been trapped by lateral and vertical facies changes which provide efficient stratigraphic trapping mechanisms.

The purpose of this paper is to recognize inferred faults in Tympaki basin (Crete island) which cannot be observed on the surface, as the area is covered by recent deposits. The identification of the faults is crucial for the study of the sea-water intrusion in Tympaki basin that has been observed during the last years. 3D geological modelling techniques were used for reaching the aforementioned goal. The data used include the digital elevation model (DEM) of the area, the boundary surface between geologic formations and the litho - stratigraphic logs of thirty nine (39) wells. Initially a 3D stratigraphic model was set-up depicting the spatial extension of Plio-Quaternary and Neogene deposits. Next, with emphasis on the litho - stratigraphic logs of the wells, the boundary between the geological formations was defined in a 3D space. The regional unconformity between the Plio-Quaternary and Neogene formations is possibly the result of tectonic activity of inferred faults. The traces of the inferred faults were drawn and they were compared with the faults suggested by previous studies.