They're studying c-c-cold to aid offshore drillers

Hany Hamza emerged from the cold locker wearing a wool cap, thick gloves, and warm jacket. a sign by the door read: "Danger of Asphyxiation or Hypothermia." the doctoral student from tropical India was doing research at Memorial University here on the strength of ice.

Ice, icebergs, ice floes, pack ice, snow -- there's keen interest at this city's research facilities in such cold-weather phenomena. Scientists here want to become the world's top experts in this area of research for practical reasons. The future exploitation of the province's resources hangs on mastering ice in its various forms.

In fact, this province's offshore oil and gas potential shows early signs of being large enough to be of considerable significance for the world's energy supply.

Mr. Hamza's research could prove useful in drilling for oil and in the frozen sea north of Canada. One technique, already used by Dome PEtroleum in drilling in the Beaufort Sea, is to build an artificial ice island for the drilling equipment.Seawater is pumped from under the ice and sprayed on top of the pack ice, rapidly freezing. Eventually, the ice is thick enough to support the heavy equipment. But after some time, the ice loses its strength and the island must be rebuilt.

Mr. Hamza was finding out the strength of various kinds of ice at various temperatures by tests in the cold locker, which can drop the thermometer to -40 degrees F. He has worked out a computer model of his findings for engineering purposes. To his satisfaction, the results of his model agree with findings "in the field" -- that is, out on the pack ice.

In another facility in the same building, another scientist demonstrated a machine to study the scouring of the ocean bottom by glaciers. Oil companies have found oil and gas offshore from Labrador and Newfoundland, but there is some doubt whether they can bring it ashore by pipeline. That's because icebergs breaking off the glaciers of Greenland and floating down so-called "iceberg alley" along the coast of Labrador could tear out the pipeline.

A giant berg, weighing perhaps 20 to 25 million tons, can dip 700 feet below the surface of the water. These frozen behemoths usually move along with the currents and winds at 1 or 2 knots. Underwater photographs show that a large iceberg can scrape a channel in the bottom as much as 21 feet deep for as long as 2.5 miles. Most bottom scouring, however, would not be so severe.

The scientists here at "C-Core" -- the Center for Cold Ocean Resources Engineering, Memorial University -- have simulated an iceberg driven by an electric motor and a sea bottom (a sand pile) to get a better idea of the pressures involved when an iceberg grounds. The statistics gathered from this small-scale model are blown up by a computer to get estimates of the real thing.

At the moment, Mobil Oil executives who are studying how to extract the oil from the Hibernia field 192 miles offshore from here believe a pipeline system might be feasible. One possibility would be to have a standard production platform made with steel girders, fixed to the bottom, but surrounded by a major underwater rock dike to ward off large icebergs.

But east coast manager Steve Romansky says that "right now a floating system looks like a more practical solution."

Such a system would have a semisubmersible production platform. the cluster of oil wellheads nearly 300 feet below would be drug into the rocky bottom so as not to be disturbed by a passing glacier. There would be a quick disconnect system so that the floating production platform could move away if threatened by a glacier or pack ice or a severe storm.

Mr. Romansky noted that 6,000- to 10,000-horsepower tugs can tow away smaller bergs weighing up to 1 million tons. As far south as the Hibernia field, icebergs this size or smaller are more frequent than giant bergs. the tugs run around the berg, laying down a nylon-covered steel cable; close the circle; and move the floating ice mountain far enough that its path won't endanger the platform.

But this seems impossible with larger icebergs. "There comes a break point where you are not sure who is towing whom," Mr. Romansky said. the massive bergs, moving with wind and current, are likely to pull the towboat, rather than vice versa.

Mobil production system also envisages a "shipshape storage-offloading" system -- an 800-foot-long, submarine-shaped tank. It would float mostly underwater for the sake of stability. Crude oil would be pumped out of this storage tank into a shuttle tanker to take the petroleum to market.

Such a system also involves radar and aerial surveillance to keep track of any glaciers and their paths. During the exploratory drilling of the Hibernia wells, glaciers went by some distance on each side. And pack ice did not come that far south in those years, though it has in earlier years. But Mobil must assume that sometime in the future both pack ice and glaciers could be a problem. And that problem will be much more severe if an attempt is made to produce the natural gas finds alomg the Labrador coast to the north.

Five years ago the government started a crown corporation, the Newfoundland Oceans research and Development Corporations, to specialize in research and engineering for operating in Arctic and subarctic waters, including glacier control. It was recently divested to a lawyer in trust to become a taxpaying entity and to be eligible for federal research-and-development financial assistance.

At its headquarters, scientists have devised a computer program for tracking hundreds of icebergs. At the press of a few buttons, a video display terminal shows the paths around a drilling site of some of the icebergs.

The corporation is also doing weather research and prediction. Conditions for the offshore Hibernia area, for instance, are worse than in the North Sea, manager Frank Smith noted. Once in a long time, waves might go as high as 30 meters (almost 100 feet).

The consulting firm also looks into such matters as the design of LNG tankers (liquid natural gas) reinforced for moving through Arctic ice, ice forecasting, fisheries technology, socioeconomic studies, and other ocean-related resource-development issues.

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