Cambridge, England – New methods of “seeing” through underwater lava flows to the ocean floor are being employed to further oil exploration in the Atlantic Ocean, which may increase production of oil already being extracted. For the first time, scientists at the University of Cambridge have mapped layers of hardened lava flows that measure over eight miles (12.8 km) thick in some places.
When a continent breaks apart, as Greenland and Northwest Europe did 55 million years ago, it is sometimes accompanied by a massive outburst of volcanic activity. The break in the North Atlantic produced five to ten million cubic kilometres of molten rock, which extended across one million square kilometres. Most of the rock is now underwater and buried by more recent sediments.
Using seismic methods, the scientists were able to map the layers of lava flows both near the surface and deep into the earth. Large volumes of oil have already been discovered and are being extracted in the sediments under the seabed between the Shetland Islands and the Faroe Islands. If these same sediments extend westward towards the Faroe Islands, as geological models suggest they do, there may be a lot more oil to be found.
However, because the sediments had thick layers of molten rock poured over them at the time the North Atlantic broke open, conventional exploration techniques have not been able to see through the lava flows because they reflect the seismic energy. The scientists have succeeded in developing a method of seeing through the thick lava flows to the sediments and the structures that lie beneath them.