Non-Conventional Plays in Romania: the Experience of OMV Petrom

Abstract

This paper describes the key findings of a regional study that targeted the unconventional potential of exploration assets hold by OMV Petrom in Romania. Three unconventional plays have been evaluated, including the (1) Silurian and (2) the Dogger on the East European Margin (including Moesia), and the (3) Oligocene in Maramures (Pienides). The Silurian shales are at 2-4 km depth in the gas window on Western-Central Moesia. Maturity in most cases has been reached by the Late Paleozoic and it was followed by significant exhumation during the Hercynian Orogeny. The quality of Silurian shale represents a major uncertainty, due to the sparse dataset represented by old wells. The Dogger shales of Northern Moesia are in the oil and gas window under the most external thrusts of the Carpathians at depths that exceed 4 km. The shales have TOC values up to 6 %. Oligocene shales with TOC of up to 10 % in Maramures are in the oil window at depths of less than 2 km. This makes them a very attractive target for shale-oil exploration. However, major setbacks are the complex tectonic structure, rugged topography and large-scale exhumation. Ongoing exploration efforts for non-conventional plays are targeted to define the mechanical properties and the exploration sweet spots in the above mentioned plays, but also assessing the potential of the Late Paleozoic bituminous dolomites of Moesia and other black shales in the Carpathians.