Over the last century, oil and gas (hydrocarbons) have come to form one of the principal energy sources supporting human economic development and welfare. Hydrocarbons currently account for 56.79% of the world's consumption of primary energy (BP, 2016). This trend is forecast to continue over coming decades, in both developed western nations and in emerging economies (International Energy Agency, OECD/ IEA, 2012a, b).
Hydrocarbons were already being produced in the Basque-Cantabrian Basin (BCB) from as early as the eighteenth century. In the Maeztu area of Alava, oil was extracted from the pores of various surface reservoir rocks.
Once the value of oil as a basic energy source came to be understood, these traces of oil on the surface attracted further surveying.
Indeed, since the early twentieth century, the basin has been one of the leading targets of onshore and offshore exploration on the Iberian peninsula.