Treasure of Khan

Tatiana unrolled a map of the lake and pointed to an area forty miles north of the town.

"We shall survey here, at Peschanaya Bay," she told the geologists. "There have been numerous surface oil slicks reported by the fishermen in this area, which would seem to indicate a hydrocarbon seepage."

"You're not going to take us sniffing around in deep water, are you, Tatiana?" Wofford asked.

"I understand the limitations of the equipment available to us. Though we have a number of potential seeps in the center of the lake, I realize the depths are too great for us to survey in those regions. Our research objective is focused on four locations in the south of Lake Baikal that are all near the shoreline, presumably in shallow water."

"We'll find out easy enough," Roy replied as he plugged a waterproof data cable into a three-foot-long yellow towfish. In addition to providing an acoustically derived image of the lake bed, the side-scan sonar sensor would also indicate the relative bottom depth when towed.

"Are the sites all located on the western shoreline?" Theresa asked.

"Only the target area in Peschanaya Bay. We must cross the lake to the other three sites, which are on the eastern shore."

The old fishing boat motored past the docks of Listvyanka, passing a hydrofoil ferry slicing into port on its return from a transport run to Port Baikal on the opposite shore of the Angara River. The sleek enclosed passenger ferry looked out of place beside the small fleet of aged wooden fishing boats that filled Listvyanka's waters. Escaping the small harbor, the fishing boat turned north, hugging the craggy western shore of the cold lake. Deep, rich forests of taiga marched down to the shoreline in a carpet of green, interspersed with rolling meadows of thick grass. The rich colors of the landscape against the crystal blue lake made it difficult for Theresa to picture the stark bitterness of the region in the dead of winter, when a layer of ice four feet thick covered the lake. A shiver at the thought made her glad she was visiting when the days were longest.

It was of little matter to Theresa, though. The petroleum engineer's true love was traveling and she would have gladly visited the lake in January just for the experience. Bright and analytical, she had chosen her career less for the intellectual challenge than for the opportunity to travel to remote places around the globe. Extended stints in Indonesia, Venezuela, and the Baltic were broken up by the occasional two-week assignment like this one, where she was sent to survey an offbeat prospective oil field.

Working in a man's field proved to be no setback, as her vivacious personality and humorous outlook on life easily broke down barriers with men who weren't already attracted to her athletic build, dark hair, and walnut eyes.

Forty miles north of Listvyanka, a shallow bay called Peschanaya cut into the western shoreline, protecting a narrow sandy beach. As the captain nosed the boat's prow into the bay, Tatiana turned to Theresa and proclaimed, "We will start here."

With the engine thrown into neutral and the boat drifting, Roy and Wofford lowered the side-scan sonar towfish over the stern as Theresa mounted a GPS ante

"Not too deep, that's good," Theresa said as the boat moved forward again, towing the sensor a hundred feet behind. A digitally enhanced image of the lake bed scrolled by on a color monitor that captured the processed sound waves emitted from the towfish.

"We can acquire meaningful results as long as the depth stays under fifty meters," Wofford said.

"Anything deeper and we'll need more cable and a bigger boat."

"And more caviar," Roy added with a hungry look.

Slowly the fishing boat swept back and forth across the bay, its hardened captain spi

As they reached the northern edge of the bay, Theresa stood and stretched as the captain swung the boat around and aligned it for the last survey lane. Toward the center of the lake, she noticed a large dirty-gray ship sailing north. It appeared to be some sort of research vessel, with an old-style helicopter wedged on the stern deck. The rotors on the helicopter were sweeping in an arc, as if preparing to take off. Sca

Geophysicists, microbiologists, and environmental scientists migrated from around the world to study the lake and its pure waters.

"Back on line," Roy's voice shouted across the deck. Twenty minutes later, they reached the southern edge of the bay, completing their multilane sweep. Theresa determined that there were three lake bed structures seen with the sonar that would warrant further examination.

"That wraps it up for the opening act of today's program," Wofford said. "Where to next?"

"We will cross the lake to a position here," Tatiana said, tapping the map with a slender finger.

"Thirty-five kilometers southeast of our current position."

"Might as well leave the sonar in the water. I don't think this boat can go much faster than our survey speed anyway, and we'll get a look at the water depths as we cross over," Theresa said.

"No problem," Wofford said, taking a seat on the deck and stretching his legs up onto the side railing.

As he casually watched the sonar monitor, a quizzical expression suddenly appeared on his face. "That's odd," he muttered.

Roy leaned over and studied the monitor. The shadowy image of the lake bottom had abruptly gone haywire, replaced by a barrage of spiked lines ru

"Towfish bouncing off the bottom?" he asked.

"No," Wofford replied, checking the depth. "She's riding forty meters above the lake floor."

The interference continued for several more seconds, then, as abruptly as it started, it suddenly ceased.

The contours of the lake bottom again rolled down the screen in clear imagery.

"Maybe one of those giant sturgeon tried to take a bite out of our towfish," Wofford joked, relieved that the equipment was working properly again. But his words were followed by a low, deep rumble that echoed across the water.

Far longer and lower pitched than a clap of thunder, the sound had an odd muffled quality to it. For nearly half a minute, the strange murmur echoed across the lake. All eyes on the boat sca

"Some sort of construction?" Theresa asked, searching for an answer.

"Maybe," Roy replied. "It's a long ways off, though."

Glancing at the sonar monitor, he noticed a brief spate of noise that minimally disrupted the image before a clean contour of the lake bed reappeared.