Coal Search In North Sea

Press, Volume CIV, Issue 30678, 18 February 1965, Page 8

Coal Search In North Sea

(N.Z.P.A.-Reuter) LONDON. Britain’s inland coal reserves are diminishing and geologists have turned to offshore exploration. So far, they have found sufficient coal off-shore to supply the country’s needs for the next century—even though the demand for fuel is expected to increase fourfold by the turn of the century. Britain’s reserves of coal, the only indigenous fuel, have been mined since the Middle Ages and intensively worked since the 19th century.

Now, with the rapid exhaustion of the inland workings, particularly in the rich coalfields in the west, the future of Britain’s coal industry clearly depends on the successful exploration and development of off-shore reserves. Appreciating its diminishing source of fuel, the National Coal Board began prospecting the bed of the North Sea and the Firth of Forth in Scotland 10 years ago. Workable Deposit With two off-shore boring towers, geologists have already proved the existence of 1500 million tons of workable coal beneath Britain’s northern coastal waters. The National Coal Board, a

state-owned corporation, was, perhaps the first major organisation in the world to undertake a systematic and scientific geological survey of the seabed for coal reserves. From its small beginning 10 years ago, the programme has developed into a longterm operation costing about £15,000,000. In May, 1955, the Coal Board launched its first seaboring tower at St. David’s harbour, not many miles from the Culross venture, off the Fife coast. This was the first serious attempt to discover the location of undersea coal reserves by boring through the seabed. Borings were later undertaken on the south side of the Forth, off Musselburgh, and the picture soon emerged of a sufficiently large field of coal to support at least two collieries.

The Seafield Colliery, off the coast of Fife, is now almost completed and production is expected to start this year.

Tentative estimates of coal reserves under the Forth are 200,000,000 tons. The Firth of Forth explorations were completed in 1958 and prospecting began in the rough waters of the North Sea. A new tower was built at a cost of about £250,000 (a small amount compared with the £1,500,000 to £2,000,000

sterling needed to build a prospecting tower used by oil companies) and boring began off the north-east coast in August, 1958. Exploration has since continued along a line running from Blyth, in the north, to the Hartlepools, in the south, Seventeen holes have now been drilled at depths from 1200 feet to 2600 feet over an area three to five miles from the coast. Seams On Seabed

The exploration areas cover 75 square miles and it is already estimated that sea coal lies in seams three to

seven feet thick throughout the area. The drilling tower which seeks out this wealth is a self-contained unit designed on the lines of the forts built round the south coast of Britain during the World War 11. The 237-foot high tower, weighing 700 tons, can start drilling within hours of reaching the chosen site. Mounted on the top deck is the drilling rig, a pump house, water and storage tanks and a specially designed core shed, which can store up to 400 feet of core at a time. Beneath the top deck lies the accommodation area for 20 men. It has 18 singleberth cabins with every modern convenience from refrigeration to television and laundries, ■ i Three Shifts The men, who work three shifts for three weeks, with one week'of shore leave, find life on the tower a cross

between living on a lighthouse and a luxury ocean liner. The tower has full lifesaving equipment and is linked by radio-telephone to shore air-sea rescue organisations, and the lifeboat and coastguard services. Mr George Armstrong, the Coal Board’s chief geologist, said that the safety record h a( j been "amazing ” Drilling operations follow a pattern similar to those on

land, but the tower can be floated, after each borehole has been completed, to another site.

The “sparker” technique is used fdr the marine geophysical survey. This is based on electronic impulses to provide information on the depth and inclination of coal seams between boreholes, and the strata and major faults in the seabed. This method was used during the seabed survey to determine the possibility of constructing a tunnel under the English Channel, between Britain and France. The major risk in the North Sea is storms. Waves 40 feet high have been known to lash the tower and at times the sea has been too rough for boats to come alongside. But drilling has never been stopped. The end of the current programme of North Sea exploration is in sight and, Mr Armstrong says, drilling has “proved enough to support the output of at least four major colleries for the rest of the century.”