National Geographic : 1978 Nov
The planners are turning to massive engineering projects for new gas supplies. Liquefied natural gas (LNG), chilled to mi nus 260 0F and imported by tanker from Al geria or Indonesia, may cost five dollars per thousand cubic feet delivered to U. S. pipe lines by 1985-more than double the con trolled price of new domestic gas. The 4,800-mile Alaska gas pipeline also will re quire a five-dollar price, as would synthetic gas produced from coal in a series of pro posed 1.6-billion-dollar plants backed by the government. "But we could drill a thousand explora tion wells for the cost of one coal-gas plant," says my government friend. "If we're wrong about unconventional resources, we'd soon find out. If we're right, we'd find huge new energy supplies in our own backyard-with a very good chance that they'd be cheaper than the alternatives, and reduce our dependency on imported fuels." Methane Pervasive in Nature Nature's gas isn't hard to find. Cows belch it. Swamps bubble with it. You can make your own by mixing organic waste with water in an airtight tank. Anaerobic bacteria digest the waste and produce meth ane, the principal ingredient of natural gas. They've been doing it for four billion years, helping make methane the world's most per vasive hydrocarbon. Finding petroleum hydrocarbons-gas and oil-is more complex. It's a gambler's game, and nature has stacked the deck. Petroleum was formed in organically rich sediments laid down over millions of years on the margins of long-vanished oceans. Partially decayed by bacteria, the organic matter was "cooked" into oil and gas by heat, pressure, and chemical reactions as layer after layer of sediment pressed down to create deep basins in the earth's crust. Nature shuffled and reshuffled the cards, alternating rich layers of fine silt and chalk with beds of salt, sand, or clay. And the hy drocarbons were restless. Often dissolved in underground waters, they migrated upward or laterally to create giant reservoirs in po rous sandstone or limestone layers trapped beneath impermeable rock. Where no traps existed, they often escaped to the surface and were lost. Finally, there was a joker in the deck. In deep, hot regions, the cooking process con tinued until the hydrocarbons were reduced from liquid oil to molecules of gas. For decades oilmen treated gas as a neces sary evil. It provided most of the pressure that caused oil to flow to the surface. But it caused deadly blowouts. There was no mar ket for it. Since 1859, night skies have glared hellishly over the world's oil fields as tril lions of cubic feet of natural gas flared use lessly away (below). Not until the 1930's was the first major U. S. pipeline built to carry gas as a lowly by-product of oil. Things have changed. In the U. S., laws severely restrict flaring. Today gas travels through a million-mile, 50-billion-dollar pipeline network. Eighty percent of our sup ply comes from the gas-only reservoirs dis dained by the oil pioneers. The legacy of that disdain lives on. For years gas price controls were based on its by product status. Researchers concentrated relatively little effort outside the areas where oil, vastly more profitable, might be found. Unconventional gas resources were largely ignored and poorly understood. Now that, too, is changing. A new breed of pioneers, armed with new technology and new ideas, has entered the gambler's game.