Scientists explore remotest frontier, just off New Jersey Seafloor bed of mud 6 miles thick draws ocean drilling project

THE BALTIMORE SUN

ABOARD THE JOIDES RESOLUTION - The helicopter flew north past the garish gambling hotels that line the Atlantic City shore, then made a sharp right turn out to sea in search of a different kind of gambling operation. An hour later, some 108 nautical miles east of Atlantic City, a tall derrick suddenly pierced the enveloping cocoon of summer haze, and the helicopter set down a group of reporters on the deck of the Joides Resolution.

Named after HMS Resolution, in which Capt. James Cook roamed the southern seas in the 1770s, the modern vessel explores the remotest of all frontiers, the regions beneath the ocean floor. It drills holes deep into the sea bed, retrieving cores of mud and rock from which scientists strive to interpret the Earth's distant past and forecast its long-term future.

The Joides Resolution is usually to be found on the high seas, probing through several miles of ocean water with its slender drillstring. The New Jersey coastline makes an oddly suburban habitat for this ocean-going vessel. Nearby is the site where New York sewage sludge was dumped for years. Beneath the ship lie a mere 2,000 feet of water and a bed of mud six miles deep that has built up over the last 36 million years.

It is an invisible trove buried in the mud that has lured the the ship into such shallow waters.

Answers in sediments

The Joint Oceanographic Institutions, an international consortium based in Washington, has two scientific directors, who hold sway in alternate 12-hour shifts.

This voyage's co-chiefs, Dr. Nicholas Christie-Blick and Dr. James A. Austin, are trying to measure the rise and fall of sea level over the last 35 million years. Their hope is to figure out how much was due to up-and-down movements of the land and how much to depletion of the oceans when water was locked up in the glaciers of the great ice ages.

New Jersey's mud may hold many of the answers. The sediments are packed in a neat but complicated pattern of layered wedges. The boundaries between the wedges seem to represent the changing level of the beach as sea level rose and fell. Deciphering the pattern may help explain how climate and sea level responded to past changes and how they will behave under future stresses, like greenhouse warming.

Getting to use the Resolution and its unmatched capabilities is as precious an opportunity for geologists as observation time on the Hubble space telescope is for astronomers. Christie-Blick and Austin spent nearly a decade planning the voyage and persuading fussy committees that their plan was adventurous yet almost risk-free.

The ship has now been in their hands for nearly a month. They have a captain who will take them wherever they want and a drilling superintendent who will punch holes in the sea floor almost wherever they say. They would be like kids in a candy store if not for the unrelenting stress.

Around the clock

The ship works round the clock. There is a team of about 50 scientists and technicians whose work must be organized and kept on schedule. The cores of mud and rock hauled up from the ocean floor have to be analyzed, and reports written up immediately. The co-chiefs must stay abreast of all these results so as to plan the next drill hole. There are decisions to be made constantly and heavy penalties for bad calls. Cost aside (the basic running cost of the ship is $45,000 a day) a poor strategy can ruin the scientists' chance of a career-making discovery.

"Co-chiefs tend to disagree a lot. Sometimes they don't get along at all well," Christie-Blick says, though he seems to be referring to infamous legs of the past. The reason, besides stress, is that the co-chiefs are often chosen for different and complementary talents. Christie-Blick is a mild-mannered Englishman now at Columbia University. A specialist in the study of sediments, he is the rare individual who is moved to rapture by getting his hands on yards of New Jersey muck.

Austin is a geophysicist and easygoing Texan, at home in the ship's two cultures of science and oil drilling. Austin, who comes from the University of Texas at Austin, is the experienced hand, having been a co-chief before.

Drilling holes in the sea floor is not like making sand castles. JTC Opportunities abound for serious mishaps, like losing equipment down a hole, and even outright disaster. One is to strike oil,

because the Resolution has no way of capping a well and preventing an oil spillage. Another is to hit pockets of gas; a large enough belch could destabilize the top-heavy ship.

Eugene C. Pollard, the ship's drilling superintendent, helps the co-chiefs sink their holes in sensible places.

Technical problems

The current voyage has had its share of technical problems. The topdrive, which spins the drill string, has acted up twice. Fat wedges of sand, New Jersey's missing beaches of millions of years ago, lie interspersed with the mud layers below. The sand sucks at the drillstring, which is hard to yank free in shallow waters. It also fills up holes before instrument packages can be sent down to take measurements.

Today the last cores of the voyage have been brought up and are being processed through the Resolution's laboratories. The long cylinders of gray mud are sliced lengthways into an archive half and a sample half. Near the very bottom of the core, at a point the ship's paleontologist has dated through its microfossils to 36 million years of age, is a crumbly whitish streak of a boundary layer. The white band may mark the shoreline of a Greater New Jersey, when sea level was several hundred feet lower than today.

Technicians take physical measurements of the sample, then scoop out small chunks of various ages and composition that have been ordered by geologists around the world. The archive half is packaged in a plastic sheaf and sent to the Lamont-Doherty Earth Observatory in Palisades, N.Y. The laboratory now holds 25,000 meters of ocean core collected over the last quarter-century by the Resolution and its predecessor, the Glomar Challenger.

Free space valuable

What the Resolution lacks is free space. Every room brims with people or equipment. Even the sea's cry is crowded out by the steady rumble of the 12 thruster motors that keep the ship poised above its drill hole.

The ocean drilling program carried out by the Resolution has helped geologists make many discoveries about the rock movements of Earth's interior and the ancient cycles of the globe's climate.

"The record of Earth's history is probably written with greater fidelity in the oceans than anywhere else on Earth," says Jeff P. Fox of Texas A&M; University, which manages the ocean drilling program. "For us to be good stewards of the planet in the 21st century we must understand that record." .

Other ships can visualize sea- floor sediments from their sonar reflections, or scoop shallow samples off the bottom. But only the Resolution can bring up deep cores and learn what is actually there. Since 1985, when the ship was converted from oil exploration to oceanographic research, its drill bit has been the recognized arbiter of geological truth.

But the ship itself faces a moment of truth because the National Science Foundation, its major patron, will drop support under a sunset clause in six years. Although the agency seems likely to renew its funding, the terms remain open to negotiation, and users of the ship will need to explain why they expect yet more discoveries to be made.

As part of its plans for the Resolution, the Joint Oceanographic Institutions would like to improve the ship's capabilities so that it can explore new and more difficult terrain. Geologists also hope that Japan will build them a dream ship, known informally as the Godzilla Maru, that will have the equipment to retrieve very deep cores without fear of oil spills.

The United States contributes $28 million to the consortium's $44 million Ocean Drilling Program, with subscriptions from some 20 other countries making up the balance. To achieve their goals, the ocean-going geophysicists of the consortium need to raise more money from the United States National Science Foundation, or to drum up more member subscriptions.

Within the United States there are the usual tensions between geologists who back the big science the Resolution can undertake and those who fear that their individual research programs will get squeezed out.

On the Resolution, the last core has been analyzed and packed away. Christie-Blick and Austin need to send an instrument package down their latest bore hole, and their cruise will be over. Then it is back to the laboratory to see whether their precious cores hold a decipherable record of sea-level change, or just mud.

! Pub Date: 7/24/97

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