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The petroleum system in Central Italy and the Adriatic Sea is of great interest for future hydrocarbon exploration. However, major uncertainties remain about key risk elements such as source rock spatial distribution and maturation history, the timing of hydrocarbon migration, and the nature of migration pathways. This paper presents a new regional‐scale petroleum systems model based on an integrated inter‐disciplinary study which includes public‐domain subsurface data on key petroleum systems elements, heat‐flow and petroleum geochemical data, and an extensive set of 1D basin models. Results show the importance of the Mesozoic palaeogeographic and stratigraphic setting which was characterized by the presence of platform and basinal domains. Thermal data highlight an overall higher basal heat flow in platform domains which persist at the present‐day. Considering the geochemical and thermal characteristics of possible source rocks in the study area, the Upper Triassic Burano Formation appears to be the most likely active source rock but only in those geological domains where it has been deeply buried. In particular, source rocks reached maturity only during the most recent Apennine deformation phase in the late Pliocene/early Pleistocene, i.e. after the deposition of regional seals such as the Messinian Gessoso‐Solfifera Formation. Lateral migration is suggested to have occurred to explain most of the known oil accumulations. The margin of the Apulia Platform could have acted as a migration pathway for hydrocarbons, connecting basinal kitchens to the carbonate reservoir units at the top of the platform succession within which oil and gas accumulations have been proven. Heavy oils could represent early expulsion products from the source rock, but may also locally be a result of biodegradation due to recent partial exhumation of the traps and the loss of lighter components. The results of this study may support ongoing and future exploration efforts over other carbonate platforms in the study area, and more widely on carbonate targets elsewhere in the Mediterranean region. [ABSTRACT FROM AUTHOR]

Basin modelling represents an important approach for the prediction of hydrocarbon generation/migration, identifying possible prospects and reducing the risk in exploration areas. This modelling can be also used to study the structural evolution of an area. Main input are the thermal/burial history of the sedimentary basin (key parameters for source rock maturity) and the adopted crustal model. We applied a basin modelling approach to the study of a portion of the Central Apennine orogen (Central Italy), where both thick-vs thin-skin interpretation models were historically proposed, and to the adjoining Central Adriatic foredeep/foreland system, to contribute reducing the tectonic and petroleum system uncertainties of this structurally complex area. We started from the available dataset obtained from the past hydrocarbon exploration activities, that resulted in several small/medium oil discoveries (evidence of an active petroleum system), making a structural review of the different crustal models proposed by the literature. We built two balanced 2D regional sections using MOVE software: one across the off-shore Central Adriatic foreland; and one from the front of the Central Apennine through the Central Adriatic foredeep/foreland system. This last section was modelled testing both a thick and a thin-skin structural scenario, implementing a structural restoration step using Dynel2D software. Using PetroMod2D we then compared the obtained petroleum system results to verify which structural scenario better fit with the present-day known distribution of hydrocarbon occurrences, both on-shore/off-shore. A 3D model was then implemented over key sectors to better understand the main hydrocarbon generation trends. Results suggest the thick-skin model as most suitable to justify the known hydrocarbon occurrences in the area. In addition, modelling indicates a lateral hydrocarbon migration as a key process for known hydrocarbon accumulation, active from the Upper Miocene (in the Central Apennine foredeep) and Upper Pliocene (in the Central Adriatic foreland) to present-day. • The Central Apennine Thick-Skin model can justify the known hydrocarbon occurrence. • The excessive hydrocarbon generation of the thin-skin model is not compatible with the on-shore/off-shore oil&gas occurrence. • The Lateral hydrocarbon migration is the key process to explain known oil accumulations. • The structuring of the Central Apennine is a key factor for the petroleum system activation. [ABSTRACT FROM AUTHOR]