This prospection involves areas of the Spanish coast: Balearic Islands, Comunitat Valenciana and Catalonia.

Currently in the exploration phase, Cairn Energy (though its subsidiary company Capricorn Spain Limited) plans to carry out sonic imaging (by the company Seabird Exploration), but environmentalists warn the sonic shocks used in seismic imaging are a threat to marine life and will negatively impact fisheries with some alleging that the impact of the seismic tests could reduce fishing hauls by up to 70 percent. Meanwhile, there have also been allegations of faulty environmental impact studies performed between 2012 and 2013.

Another company, Spectrum Geo Limited, has requested a license to explore the Gulf of Lion and the southern strip of the Balearic Islands.

On the other hand, there is an ongoing oil exploitation by the Spanish company Repsol on the coast near Tarragona.

Opposition to these projects has been widespread and the regional government of the Balearics, headed by Popular Party (PP) premier José Ramón Bauzá, opposes any plans to drill for oil offshore, as do all local councils.

In Ibiza for example, which is an UNESCO World Heritage Site, up to 50 civil servants were assigned the task of collating the thousands of letters sent in by local people registering their opposition to any drilling.

The Alliance Mar Blava unites over 50 organizations on the island, including business, environmentalist groups, unions and fishermen, and aims to completely stop the investigation (and subsequent exploitation) of hydrocarbons off the west coast of Ibiza and Formentera in the gulf of Valencia. Its purpose is also to preserve the environmental richness that makes the Balearic Islands a unique place, as well as safeguarding the employment and wellbeing of its residents and the rights of future generations to enjoy a well preserved environment.

They argue that oil exploration represents a threat to the environment (coastline and wetlands), biodiversity (flora and fauna, including several cetaceans species) and the economy (tourist sector and fishing). As they say "tourism is our oil".

Despite this, it seems the federal government aims to move ahead with the exploration.

The project dates back to 2010 when British firm Cairn Energy obtained four exploration licenses for the waters around the Balearic Islands, one of which is Ibiza.

The company now plans to use seismic imaging, which bounces sound waves off the ocean floor, to map pockets of underground oil in the region before it applies for government permits to start drilling.

Cairn Energy said it will carry out the seismic imaging over 2,400 square kilometres (930 square miles), an area roughly the size of Luxembourg, 53 kilometres (32 miles) from Ibiza. [1]