The wildcat Naft Sefid 20 was scheduled to drill clean through the Cretaceous limestone gas cap in an effort to tap the expected Eocene formations below, which at that time had not yet been explored in Iran. Such an operation is not for the fainthearted, because gas cap pressure in vast limestone reservoirs is hard to predict.
Nevertheless, we had great confidence in our drillers, who, in decades of punching holes into the Cretaceous, would watch the cuttings screen like a hawk, figuring to within a foot when they were about to go from shale into limestone, then setting an intermediate casing string and upping the mud weight to contain the caged beast below.
But NS 20 was different. Unknown to the geologists, the location was in a new and undepleted section of the reservoir and higher than expected; the head driller had taken sick, and his stand-in was relatively inexperienced; and the rig crew were just coming off a 12-hour shift, bone-tired. Any doomsayer could have foretold what would happen next, but it was midnight, and all the know-it-alls were asleep and 20 miles away. So it happened.
First, the shaker screen cuttings changed to limestone while the new crew was still getting into their overalls, and the bit was already two feet into the gas cap before anyone took a look at the screens. By then the drill string, nearly two miles long, started to rise through the rotary table slowly, majestically, like a space rocket taking off, hinting at unbelievable power below.
Then the underweight mud came roaring out of the hole in a brown tornado. The new driller tried to close the Cameron blowout preventers, but it was too late; the outsize bolts tying the preventers to the surface casing flange snapped like matchsticks, and the rest of the drill string came out of the hole at gathering speed, taking with it the massive preventers, the giant traveling block and the whole top half of the derrick up into the air, depositing them half a mile away in a cat’s cradle of torn steel.
Finally, as the last of the mud left the hole, came the gas: a pure white column two feet wide at the base and a thousand feet high, roaring like a demented banshee and spreading out as it left the surface casing flange as if undecided whether to go up or sideways. Someone had the bright idea to shut down the gas-fired steam boilers a few hundred yards away; otherwise, we would all have been roasted. But maybe not so bright, as the immaculate gas column was carrying a healthy proportion of deadly hydrogen sulfide gas, which, being heavier than air, settled down into the hollows of the surrounding hills to become an invisible death trap for anyone unlucky enough to walk into it.
The ground for hundreds of yards around shook so that it was impossible to stand erect, and the deafening roar could be heard for miles. We hadn’t a clue what to do next, but Myron Kinley, Red Adair’s mentor, was called and showed that putting the demon back in its bottle was quite simple, provided you had the courage of a lion and all the luck in the world. Even so, it took him a year and an emperor’s ransom, but that is another story altogether.
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