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J.R.: There’s nothing realer than oil, that’s for sure.

Sue Ellen: Not to you darlin’, except perhaps money.

J.R.: Same thing, honey, same thing.

—Dallas, season two

1 Over a Barrel THE BOOM AND BUST OF AMERICA’S DOMESTIC OIL EMPIRE

The oil field known as “Jack” is located 175 miles off the coast of Louisiana, below 7,200 feet of water and another 30,000 feet under the seabed, occupying a geological layer formed in the Cenozoic Era more than 60 million years ago. This layer—the “lower tertiary”—lies beneath waters far deeper than those surrounding any other Gulf of Mexico oil discovery, which is one reason why many in the industry initially dismissed it as too remote to exploit. But in 2006, Chevron defied the odds when its engineers drilled a test well at Jack and discovered that oil could flow from this ancient sediment at profitable rates. Their success opened up a new drilling frontier—a monster oil patch holding between 3 billion and 15 billion barrels of crude. It was hailed as the largest discovery in the United States since 1968—a discovery potentially big enough to boost national oil reserves up to 50 percent.

Since then, global oil companies have been pouring billions of dollars into these so-called ultradeep waters of the Gulf in pursuit of the region’s buried treasure. Jack is among a cluster of nearly a dozen new fields there—including “Blind Faith,” “Great White,” and “Cascade”—that companies are now tapping in waters from 4,000 to 8,000 feet deep and in sedimentary rock extending between 1 and 6 miles below the seabed.

Coaxing oil from such great depths poses unprecedented risks for oil drilling—and that’s why I decided to visit the area. I wanted to witness firsthand the world’s most extreme drilling territory, the Mount Everest of oil frontiers, where the industry has to tackle the tallest odds and gravest circumstances to eke out new discoveries before global petroleum production peaks and begins to decline.

I set out at dawn on an April morning in a Sikorsky S-76 helicopter. The sky above the New Orleans heliport was a pea-soup green, thick with rain and pitchfork lightning. I was traveling with a Chevron executive and three of his staffers, all of us wearing regulation jumpsuits, hard hats, and steel-toed boots. The chopper lurched and shuddered in the squalls, but my travel companions nodded to the pilot to press on—this was typical weather for the Louisiana coast, and routine flying conditions. We hurtled over the bayou’s emerald marshlands, patterned like marbled paper with coiling blue inlets and flecks of white from puttering shrimp boats. Soon the marsh gave way to the Gulf of Mexico’s open waters and the storm lifted. I relaxed my grip on the edge of my seat as a smooth two-hour voyage stretched out before us.

“Isn’t this transcendent?” Paul Siegele shouted as he pressed his nose to the window. The early morning sun glinted off a colony of metal structures pocking the surface of the sea. Siegele, the director of Chevron’s offshore drilling division, identified the objects below with the geeky verve of a birder: a miniature oil rig known as a mono pod, a drill ship nearly as big as the Titanic, and circular, tiered platforms scattered like steel chandeliers that fell from the storm-shaken clouds.

A lanky six foot three, Siegele has none of the cowboy swagger you might expect from a top oil executive. He’s earnest and quick to smile, with a mild, professorial manner and a boyish mop of brown hair. Siegele was an aspiring artist as an undergraduate at California Lutheran University, until his studies of rock as a sculptural medium sparked his interest in geology. Oil drilling, he says, is not unlike sculpture: “It’s about precision—guiding tools into the earth artfully, not just blindly hammering at rock.”

The Gulf yields 25 percent of all U.S. oil production, and is home to more than 3,700 production platforms, most of them located in relatively shallow waters of under 2,000 feet. Many geologists believe that the ultradeep regions of the Gulf—those covered by waters greater than 4,000 feet—hold more untapped oil reserves than any other parts of the Western world. Today, offshore rigs are capable of operating in 10,000 feet of water and boring through 30,000 feet of seabed (twice the depth they could manage a decade ago). One rig sits atop each field, thrusting its tentacles into up to a dozen wells throughout the bed. The rig pulls up oil and then pumps it back to onshore refineries via underwater pipelines.

Chevron is one of the largest leaseholders in the deep-sea Gulf, which means it has much to gain from these waters—but also much to lose. Three out of four exploration wells in this area come up dry—nerve-wracking odds when the wells cost $100 million apiece, or as much as twenty times what they cost on land. And even if you hit pay dirt, there’s no guarantee of profit: in the past decade, Chevron has abandoned nearly a quarter of the successful wells it has drilled because they wouldn’t flow at profitable rates.

Our specific destination was an offshore rig known as the “Cajun Express”—a massive rectangular ship with onboard drilling equipment. It was the Cajun’s 5-mile-long drill that months earlier had burrowed the legendary discovery well at Jack. That day, the rig had motored over to a nearby field known as “Tahiti,” where Siegele would be overseeing final preparations for another drilling endeavor. (Field names are given by the geologists who discover and study them. There are plenty of fields in the deep-sea Gulf with names that carry more gravitas—“Thunder Horse” and “Atlantis,” for instance; “Jack” was named in honor of its founder’s lifelong mentor, and “Tahiti” by a geologist who loved the Polynesian islands.)

The activity we were about to witness on the Cajun would help determine the fate of this extreme deep-sea frontier: Would the risks outweigh the rewards? Would Chevron be able to scale this drilling Everest?

Truthfully, there’s no single Everest of oil drilling, given how many unthinkable extremes—environmental, technological, political—the industry and its workers face today. In the Chukchi Sea of the Arctic Ocean, for instance, drillers have to wear heated bodysuits to survive winter temperatures averaging 60 degrees below zero; the region descends into near-complete darkness for four months of the year. In the Kashagan field of Kazakhstan, workers have to wear gas masks to protect against the high concentration of poisonous hydrogen sulfide present in the oil they’re extracting. On Sakhalin Island, located in the Sea of Okhotsk off the coast of Russia, pipelines are placed in the vicinity of active fault lines, exposing workers to the ongoing threat of explosions and other disruptions caused by earthquakes. This remote territory is also home to brown bears and bandits, so security guards must stand watch. Add to that the more routine hazards of the job: five workers died in a single year on Sakhalin from accidents such as high falls. The oil wells, pipelines, and refineries of Chad, Iraq, and Iran, meanwhile, are vulnerable to terrorist attacks.

But in the minds of oil executives, one risk outweighs all others: cost. In this category, no drilling frontier is more extreme than the world’s deepest seas. And no seas are more costly to exploit than the Gulf of Mexico, where the undersea sediment is particularly difficult to map and penetrate and the oil is embedded so deep underground.

Chevron’s discovery at Jack was like spring in the autumn of the oil industry. Many of the world’s largest fields today—from Saudi Arabia’s Ghawar to Alaska’s Prudhoe Bay—are dwindling, verging on retirement. Nearly 70 percent of the world’s oil comes from fewer than eight hundred fields with an average age of forty years. Of those, only twenty-five are supergiants—a term industry insiders use to refer to fields that contain more than 5 billion barrels. Amazingly, only nine supergiant fields have been discovered worldwide since 1970, according to the International Energy Agency. Despite increasing exploration activity, the rate of supergiant discoveries has been slowing over time: Of these nine, six were discovered in the 1970s, two in the 1980s, and one in the 1990s. (Discoveries in the Gulf’s ultradeep waters have not been included in the tally, as the region is still being mapped.)

Add to that the political pressures associated with many petroleum-rich areas: three-quarters of the world’s oil reserves are controlled by nations such as Saudi Arabia, Iran, and Nigeria, which have governments that are either at odds with the United States or vulnerable to corruption and conflict. Managing drilling operations in these regions can be dangerous, costly, and unpredictable. Even those oil-producing countries that are U.S.-friendly, such as Brazil and Mexico, require American oil companies to pay high taxes to produce their crude abroad.

Taken together, these constraints on U.S. oil producers make domestic discoveries in the deep-sea Gulf momentous. But there’s a hitch—a few, in fact. Just because the oil is there doesn’t mean it can be reliably and affordably pumped up from extreme depths and into refineries and gas stations. The deeper and farther offshore you go to find oil, the bigger the technological and financial hurdles: temperatures “down hole” get ever hotter and the pressures more intense, the seas get rougher, and the likelihood of placing the drill in the right location gets more and more remote.

In short, penetrating fields like Jack and Tahiti is as much an exercise in brute mechanical force as it is an act of extremely delicate surgery—or careful artistry, as Siegele sees it—the likes of which my travel companions and I were about to witness.

INTO THE DEEP

From my helicopter window, the Cajun looked like a child’s toy—a multicolored Erector Set floating on a buoy. But once we landed and I stepped out into the salty, sunny Gulf air, the rig gave an entirely different impression, awesomely vast and imposing. Looming above us like an elephant above ants was a massive hydraulic drill encased in a 250-foot cage of steel scaffolding. The rest of the hulking industrial curios on the platform looked miniature by comparison. Siegele explained these objects and their functions as he walked me past two huge red cranes; six smokestacks releasing exhaust from the rig’s diesel generators; a robotic submarine that oversees drilling activity on the seafloor; mountainous piles of metal pipes used to tap the dormant oil bed; and steel holding tanks for the sediment, mud, and thick black crude that soon would be pulled up from below.

We entered the boxy three-story cement building that houses the dorm rooms and offices. So austere were the surroundings—and so far removed from civilization—that I found myself heartened by the daily, familiar details of a Snickers wrapper crumpled on the floor, a dust bunny underneath a desk, and a family snapshot tacked to an office wall—evidence that people actually do live and work on this floating city.

“It isn’t the Queen Elizabeth,” Siegele told me, “but we’ve got what we need.” The cafeteria was a grim, prisonlike chamber of gray linoleum and stainless steel, supplying a diet of rib-sticking but tasty fare: bratwurst, cheese fries, Frito pie, and twice-baked potatoes were the items piled on my lunch plate, for instance. The living quarters, which taken together house up to 150 workers, are each the size of a walk-in closet, crammed with two cot-sized Murphy beds. I poked my head into one room, finding that it held little trace of its occupants except for a wooden crucifix and a Sports Illustrated swimsuit centerfold Scotch-taped to the wall. These are temporary dwellings—most of the occupants work two weeks of each month, going ashore in between.

While the Cajun did have an Internet café, a gym, and a movie theater (starkly furnished venues that look more like conference rooms than recreation areas), these luxuries are rarely used. Few of the men (the rig workers I met were invariably men) have the energy for entertainment after working twelve-hour shifts on the drilling floor. There’s not much contact with family on the job: cell phones don’t work this far offshore, so workers have only the options of e-mailing (by satellite Internet connection) or calling from a community phone. And while the sapphire ocean views are beautiful, especially when painted with the pale light of dawn and fiesta-colored sunsets, the workers don’t indulge in recreational swimming. I found out why when I saw a lone dorsal fin circle the platform—this is shark territory.

But not one Cajun Express worker I spoke to complained about the unforgiving environment. As global demand for oil increases and supplies become scarcer, oil industry profits in recent years have never been higher—and there are generous salaries to show for it. Entry-level tool pushers make about $60,000 a year and high-level geologists and engineers can make in the middle six figures. There’s also the guaranteed Rocky Balboa–sized testosterone rush of this type of work: “This is the best big-boy toy you’ll ever find,” said Chevron’s public affairs manager Mickey Driver, patting a railing on the platform. “There’s more horsepower beneath this puppy than in all the engines of the Indy 500.”

Rising from the concrete floor and up through the bottoms of my boots was a strange and subtly apocalyptic vibration. “The thrusters,” said Siegele, noticing my puzzlement. Thrusters, he told me, are gigantic engines at each corner of the platform relentlessly pushing and pulling against the ocean currents. Picture yourself standing in shallow waters at a beach and incessantly shifting your weight to stay balanced as the waves surge and the tides ebb and flow. Thrusters do an extreme version of this in order to keep the rig “on station,” meaning within six inches in any direction of the drill’s charted entry point into the seabed below. Anchors can’t be used to moor drilling vessels at these depths—the motion of the ocean would strain even the strongest of moorings, and rigs need to be able to motor to safety in the event of a hurricane.

The thruster solution is ingenious, but it carries an astonishing energy burden: these 9,500-horsepower engines use a combined total of 27 megawatts of power when running at full capacity—enough to power about twenty-one thousand homes. The generators that power the thrusters and keep the lights on, the electric drill turning, and the computers humming in this village at sea require about 40,000 gallons of diesel per day. It’s roughly the amount of fuel that 13,300 Hummers consume in a typical day of driving.

PRESSURE POINTS

You have to burn fossil fuels to harvest them—that’s a reality in any drilling scenario—but the ratio of energy invested to energy gained gets slimmer as the drilling conditions get more extreme. (By “energy invested” I’m referring to all fossil fuels used to discover, drill, pump, and refine the oil and transport it to market.) During the glory days of U.S. oil production in the 1930s, an investment of 1 barrel of oil would yield a return of about 100 barrels. By 1970, when oil deposits had become scarcer and more difficult to extract and refine, the ratio had shrunk by more than half: 40 barrels of oil gained for every 1 barrel invested. By 2005, as the industry faced ever-greater limits, the ratio had diminished still further: about 14 to 1. Returns will continue to diminish, some experts argue, until we reach a 1:1 ratio; and that would spell the end of the petroleum era.

As I watched the Cajun in action, I began to understand why extreme drilling conditions can be so treacherous and demanding. It’s an expensive fuel-intensive process by itself to grind a drill into the farthest reaches of the earth; it’s an even bigger challenge to overcome the inevitable barriers and delays that occur along the way, draining more fuel and resources as the project wears on. That morning, workers on the Cajun Express had begun scraping clean the 5-mile drill hole so that perforating guns could be dropped down to the base of the well. There the guns would be triggered, releasing a spray of buckshot to loosen the sediment and stimulate the flow of oil into the well. If these highly sensitive instruments encounter unexpected obstacles on the way down, they can fire prematurely and this can permanently cripple the well. The well therefore has to be thoroughly cleared first by a tool known as a junk basket—an 8-inch-wide hunk of iron that’s forced up and down the entire 5-mile length of the hole, removing loose earth, rocks, and other possible barriers.

Halfway through our visit, Siegele took me to the rig’s control room—a small glassed-in chamber that contains a thronelike chair and a desk with a red joystick that operates the drill. I could hear the clank BOOM clank BOOM of the drill’s robotic arm sounding rhythmically as it gripped, positioned, and screwed together 90-foot sections of pipe to plunge the junk basket ever deeper into the hole. Minutes later, Siegele got some bad news. “The junk basket is stuck way down there on some debris,” reported Ron Byrd, a weather-beaten Chevron employee who has captained Gulf rigs for more than thirty years. Siegele winced almost imperceptibly. “Just a little bump in the road,” he muttered when I pressed him for details. Technically, it was a million-dollar bump. The crew would have to spend the next forty-eight hours fishing the jammed cleaning tool out of the hole, halting all other activity on a rig that costs over $500,000 a day to lease, fuel, and operate. But this is chump change to Siegele, with his annual budget of more than $1 billion. “If snags like this didn’t happen so frequently, you’d probably let them get to you,” Siegele told me, sucking in a breath of salt air. “But you can’t do these kinds of wells without stuff breaking—it comes with the territory.”

It’s one of many hazards that come with the territory. Take, for instance, loop currents. These mighty flows of water propelled by the Gulf Stream can threaten to bend or snap the drill shaft as it plunges toward the seafloor, and have to be vigilantly monitored for any directional shifts. The rig’s electrical system is also highly vulnerable—if a fuse blew, the thrusters would seize up, and the drill shaft would have to be severed. Still another challenge is guiding the drill on its optimal course down through 30,000 feet of sediment—a challenge akin to “flying above New York City in a jumbo jet, aiming a baseball at the pitcher’s mound in Yankee Stadium, and hitting it dead center,” said Siegele. The margin of error as the drill enters the seafloor is only about a meter in any direction. Any farther, and chances go up that you’ll hit a fault line or air pocket that will throw the whole well off.

Charting the course of the drill is an implausibly difficult task of its own. “We’re pretty much shooting in the dark,” said Siegele. Chevron runs its offshore drilling operations out of a gleaming Houston skyscraper that’s the shape of twin cylinders, resembling the nose of a double-barreled shotgun aimed skyward. The company devotes billions of dollars annually to mapping out the subsea landscape of its deepwater fields on high-tech equipment at this location, but there’s a limit to what these maps can show.

Geologists work in cavernous visualization rooms with floor-to-ceiling monitors and computers that have the processing power of “a PlayStation the size of an eighteen-wheeler,” as one engineer described it to me. The computers crunch seismic data that are then translated into maps of ancient sediment. To collect the data, geologists deploy ships that cruise above deep-sea prospects and pop off air guns—underwater cannons that emit gigantic burps of air into the ocean, bouncing sound waves off the underwater rock formations. Aquatic microphones tethered to the vessel record the response.

Gathering seismic data for subsea oilfields in the Gulf of Mexico is far trickier than in other offshore drilling regions. The sediment beneath the Gulf has a salt layer that’s as massive and ragged as the Swiss Alps; this layer acts like a fun house mirror for sound waves, deflecting and distorting them in ways that other sediments don’t. So Siegele’s team had to trigger multiple air guns at once while microphones took hundreds of thousands of recordings simultaneously. The vast constellation of data points enabled Chevron’s seismologists to unscramble the salt layer’s distortions. Still, the maps were largely inscrutable. “Reading these maps is like looking through a wall of thick glass brick,” as one geologist told me, “and trying to count the eyelashes of a person on the other side.”

The maps also can’t predict how hard it will be to extract the crude. You might think of oil as situated in big pools under layers of rock. But it’s actually embedded in the rock, like water in a sponge. “When you drive the drill down you’re going into porous rock that can be either kind of squishy or kind of rigid,” Siegele explained. Squishy is better, but as rocks age in deeper terrain, they typically become tighter—meaning less productive. You also confront more debris that can clog the well shaft: in other words, instead of sucking up the oil in one big swig like a soft milkshake, it’s as though chunks of ice and strawberry get stuck in the straw. That’s why, when I visited the Cajun, teams of geologists were standing by to analyze the rocks and mud that got pulled up by the junk basket, hoping to gather a better understanding of the conditions deep below.

Temperature and pressure also pose risks to drilling activities, so engineers must vigilantly scan the computer readouts that monitor these conditions as machinery travels down through the sediment, crossing geological layers that range from hard bedrock to sand to empty voids. The rapid pressure changes between these layers routinely disturb equipment. At the well bottom, there is enough pressure to implode a human head—or more pertinently, to crack iron casings. And the closer you get to the earth’s core, the hotter the rocks become. At 20,000 feet below seabed, the oil is hot enough to boil an egg. At 30,000 feet, the oil can reach over 400 degrees Fahrenheit, hot enough to cook off into natural gas or carbon dioxide. Meanwhile, the water at the bottom of the deep sea is at near freezing temperatures, creating a dangerous contrast as the oil is pulled up.

Any one of these factors—loop currents, faulty drill placement, electrical glitches, rock porosity, pressure and temperature changes—could delay operations for days, weeks, even months. At more than half a million dollars a day, the operating costs add up on deep-sea rigs like the Cajun. Hurricanes, too, pose an ominous threat. In 2005, the year of Katrina, Chevron had to carry out seven emergency evacuations. BP’s legendary Gulf of Mexico platform Thunder Horse suffered a $250 million blow when a hurricane tore a tiny hole in its hull that eventually sank half the rig, requiring a stem-to-stern reconstruction.