The expedition in the vast Siberian lake, which started on Tuesday and will run for two years, is focused on studies of the lake's unique ecosystem, but researchers have also said they will be looking for 'archeological artifacts'.
Among the many 'artifacts' rumored to have disappeared into Baikal's depths are several sacks of gold, taken from the Imperial Russian reserves and carried across the ice by Admiral Alexander Kolchak's White forces fleeing the Bolsheviks in the winter of 1919-1920. Some of the officers reportedly froze on the ice in 60 degrees of frost, and the treasure sunk when the thaws came.
Although the Kolchak story is unproven, several other cases of lost treasure have been documented.
Russian tabloid Moskovsky Komsomolyets quoted explorer and treasure-hunter Sergei Nadyozhdin as saying: "some cases in which money and other valuables went to the bottom of the lake are known from documents."
He cited an incident in December 1886, when seven horse-drawn carriages carrying 1,000 silver rubles each attempted to cross the lake ice. The ice cracked, and the leading troika sunk in the lake a few hundred meters from the shore, while the rest rushed back to land, with the result that "several poods (16 kg units) of silver still lie at the bottom."
The paper quoted historian Veniamin Kropotkin as saying: "Over the past 150-200 years, plenty of goods have sunk to the bed of the 'world's purest lake' - carts, wagons, steamships, automobiles."
In 1993, ice on the rail line near the village of Tankhoi caused an entire freight train to hurtle into the water, where it remains to this day, he told the paper.
"Divers have already tried to investigate some objects, which sunk in shallower waters. On the lake's bed near the village of Listvyanka, for example, an old 1.5-meter cannon was discovered," the historian said.
The ongoing expedition in what locals call the 'Sacred Sea', led by Russian lawmaker Artur Chilingarov, received a setback on Wednesday when a propeller of one of the mini-submarines being used to plumb the lake's depths broke while the vessel was being lowered into the water from a barge.
Expedition member Anatoly Sagalevich told reporters on Thursday that repair work on the Mir-2 mini-sub, which is working alongside Mir-1, has been completed, and that the expedition will resume on Friday.
Lake Baikal, whose age is estimated at 25 million years, holds around 20% of the planet's freshwater and is home to hundreds of unique species of fauna and flora. The two-year expedition will include around 160 dives in various parts of the lake.