Better oil exploration

UK-developed monitoring techniques could save the oil and gas industry hundreds of millions of pounds a year in its continued search for untapped resources.



Working with £1m worth of funding from a consortium of the world’s leading oil companies, a Liverpool University team hopes to improve methods used to find oil and gas reservoirs within deeply buried submarine channels known as slope channel reservoirs.



Dr David Hodgson, a chief researcher at Liverpool’s department of Earth and Ocean sciences, said the oil giants are eyeing these channels increasingly enthusiastically. He explained that much of the oil exploration off the coast of West Africa, Nigeria and Brazil is being carried out in slope channels and that for companies such as Exxon and Total, they represent their biggest fields.



However, while some of these channels are filled with sand, others contain mud and silt, and oil is usually found beneath the former because it has a degree of porosity and permeability, he said.



The oil industry currently uses a combination of speculative drilling and traditional seismic response techniques. But while engineers can gain a reasonable understanding of the geological conditions, they are unable to find out enough about the sedimentary characteristics.



So, based on analysis of ancient submarine channels now above water, Hodgson’s group is developing techniques for determining which underwater channels are likely to contain sand and which are likely to be filled with mud and silt. To gain an understanding of how sand is transported through and deposited in deep-sea submarine channels, the team has been using a combination of ground-penetrating radar, differential GPS and laser imaging techniques to analyse a number of ancient channel systems in the Karoo area of South Africa.


The group is now developing an analytical method that Hodgson hopes will eventually be used by oil companies to determine whether slope channel reservoirs actually contain oil.