European prospective unconventional hydrocarbon shales: a prior approximation for resource assessment parameterisation based on European analogies

In a European wide project, including Ukraine, 81 shale formations from 33 thermogenic and two biogenic gas bearing onshore basins were studied for hydrocarbon potential. All formations have been mapped and data complied based on information and expert judgments gathered from the respective European National Geological Surveys. Parameters relevant for resource evaluation purposes were gathered for each shale layer according to the current, publically available knowledge. The description also includes a full bibliographic reference database with more than 250 references comprising the current state of the art of scientific research of European shale gas and oil. Average properties for all European shales and for typical Carboniferous and Jurassic shales are presented, applicable as a prior approximation for resource assessment parameterisation based on European analogues. The European shales compare well with prospective North American shales with respect to lateral extent, thickness, TOC content, and maturity. The European prospective shales are, however, dominated by more clay rich rock types than producing North American shales. High clay content is known to pose engineering related difficulties during drilling, completion and production; hence it may pose challenges for successful implementation of North American shale gas and oil technologies to Europe.