A Tropical 'Rain Gauge'

Revealing Secrets in the Depths of South America's Largest Lake p.5

Then it was time to move. Baker, Fritz and Broda-briefly returning from Woods Hole-climbed on the Neecho's deck while Seltzer slipped into the driver's seat. The coring crew was aboard the platform, now named the Kerry Kelts in honor of a deceased University of Minnesota researcher. The slow tow began with Neecho briefly belching black smoke. Soon boat, towing cable and barge formed an arc gently swinging up Lago Hui'aimarca's middle bound for Lago Grande. As they moved out of Huatajata, the 20,000-foot snowcapped mountains of the Cordillera Real revealed themselves behind the steep shoreline.

By the next evening Baker was aboard the Kerry Kelts to help lead the first coring operations after a 30-minute hydrofoil ride from the hilly city of Copacabana, where researchers and corers slept. The rainy season was supposed to be over as the Altiplano moved towards fall. But, while the days were sunny, the nights brought tempests. Initial coring operations on the stormy Great Salt Lake showed the platform was strong. But still, Great Salt Lake wasn't Titicaca. And Baker's shift worked at night. "When we were out the first night we had no idea how good the platform was going to be, and we got pounded," he recalled later.

The Kerry Kelts coring rig was designed to drop strings of connected pipe as far as 2,600 feet below Lake Titicaca's surface. It used a technology called "wireline coring," which allows inner cylinders containing core samples to be pulled back to the surface with cables, while outer pipes ream and cut into the mud. There was a choice of different coring and cutting ends to be used in different kinds of lake bottom deposits. But without using "driller's mud," a lubricant the scientists rejected in Lake Titicaca for environmental reasons, the technology could be defeated by sand, which bogged down and repeatedly snapped the rig's rotating connections. After eight frustrating days, they gave up on Site 1 after penetrating the lake floor only 164 feet. It was supposed to be "our prime site," Baker said ruefully.

Site 2 was a full hour's hydrofoil ride out into Lago Grande, an arm of Titicaca expansive enough to see no land on the far horizon. That put the platform further away from rescue. The lake floor was also 754 feet below the surface. That was deeper than the platform was designed to anchor. Drilling nevertheless began and continued for five days and nights, though very little got done most nights given the continued storms. "By 8 o'clock we were getting hit hard," Baker said, "with rain, sleet, snow, hail and lightning." Sometimes the waves would break over the small "shacks" installed on the Kerry Kelts' deck to shelter drillers and scientists. "At first we were just standing by with our survival suits right next to us," he vividly remembers. "Then, after we weathered one really bad storm, I wasn't worried about the platform anymore." Despite the obstacles, Kerry Kelts' drillers managed to penetrate 446 feet into the sediment, taking the scientists far back in time. "My guess is we have 100,000 years here, and five glacial cycles," Baker estimated.

Site 3 was back in the calmer waters of Lago Hui'aimarca, only 20 minutes hydrofoil ride from the Inca Utama Hotel. Baker called it "a piece of cake" to core, even though "it snowed every night on the platform, and there was lightning." Working in only 134 feet of water, the drillers managed to penetrate 410 feet down before "we hit big chunks of gravel," Baker reported. Back in his Duke office in late July, with core analysis still underway, Baker said the more extensive probing of the lake was worth the effort. "Depth wise, we didn't get everything we wanted. But I think scientifically we got everything we wanted. It would have been nice to get more meters. It was impossible to get more.

"There's probably no way you can get any more anywhere in Lake Titicaca."

Baker said he is now hatching a new research idea that would tap his own expertise as well as those of his river-studying wife and a University of California at Santa Barbara anthropologist's. This study would zero in on the "pre-ceramic" period of human culture on the Altiplano, about 4,000 years ago, when hunter-gatherers were on the verge of beginning to put down roots.

One of Baker's tasks would be to learn even more about the climate by probing other, smaller lakes.

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