Marina Salye: Distinguished geologist who became a vociferous opponent of Putin

Marina Salye was a geologist of considerable repute, locating mineral deposits in the furthest and least hospitable reaches of the Soviet Union and producing dozens of academic papers and six monographs. But she came to prominence as a pugnacious and eloquent leader of the perestroika-era democratic movement in Leningrad, and as a sharp critic of Vladimir Putin ever since she uncovered gross financial malpractice in his St Petersburg office in the early 1990s.

The Salye family was steeped in science – Marina was the fourth generation of geologists – and exemplified the intellectual culture and heritage that helped forge St Petersburg as the nation's Western-leaning capital. Her forebears were nobles from Western Europe, who all brought their service and outlook to the tsars' courts. By the 20th century, such families were cornerstones of Russia's progressive intelligentsia and professional class. Unlike some, the Salyes accepted the 1917 revolution – Marina's grandfather fought on the side of the Reds – and stayed.

Yet by the time of Marina's birth in Stalin-era Leningrad in 1934, her foreign and privileged roots were toxic, her grandfather denounced as a class enemy, her uncle arrested and sent to the Gulag. Her father Evgeny's expertise and value to the Soviet state as a uranium prospector allowed him to escape the purges by excavating in Central Asia, to where he evacuated his family from Leningrad in 1942, after being heavily wounded defending the city against the Germans. On the epic journey to Uzbekistan, the seven-year-old Salye witnessed refugees' boats being sunk by German bombers in Lake Lagoda, and a nation in turmoil. On the return journey, by cattle-truck in 1944, she saw her mother die of blood poisoning; she was buried at a siding in the Central Asian steppe.

But two years living on geology camps in barren mountains and in cramped accommodation in the Ferghana Valley had given the young Salye a taste for scientific exploration and travel that would inspire her to follow her father. She excelled at Leningrad State University, where she graduated as a geo-chemist. Her postgraduate work was in mineral extraction, and she was soon participating in expeditions that shaped her career.

Throughout the 1960s and 1970s Salye travelled to the country's extremities in the Kola Peninsula, Karelia and Yakutia, as well as to Central Asia and the Caucasus Mountains. Her academic base was the Leningrad Institute of Precambrian Geology and Geochronology, part of the Russian Academy of Sciences. By the 1980s she was travelling less, and by 1986 had become the Institute's deputy director – the pinnacle of a career for a woman in the Soviet sciences.

It was the type of career beloved by the Soviet intelligentsia, far from the constraints of politics and ideology. In the perestroika era of the 1980s, everything changed. Well-connected in Leningrad intelligentsia circles, a skillful organiser and strategist, she became a key member of the Leningrad Popular Front, a pro-democracy movement. Her skills as an orator and apparent disregard for arrest while leading demonstrations meant that she became known as the "babushka of the Russian democratic revolution".

In 1989 elections the Popular Front took control of Lensovet, the Leningrad Town Soviet, but instead of Salye, they chose the debonair Anatoly Sobchak as Mayor. Salye built links with figures in nationwide democracy movements, such as Yeltsin's future Prime Minister and free market reformer Egor Gaidar, and headed the Lensovet Commission on Food Produce. It was in this capacity that Salye ran into Vladimir Putin, a KGB operative working for Sobchak.

At the end of 1991, struggling with the deprivations and shortages of the collapsing Soviet economy, Salye became aware of an extraordinary scheme run by the Committee for External Economic Relations at the Mayor's office, headed by Putin. Leningrad, now renamed St Petersburg, was in dire straits, but contravening government rules, Putin's committee was issuing licenses to companies to export millions of dollars' worth of raw materials, under the obligation to barter abroad for foodstuffs to be brought back. Salye was shocked to discover that little or no food was finding its way back.

She headed a commission to investigate, and found a catalogue of irregularities. The companies were being awarded commissions worth millions of dollars, and raw materials such as rare metals and timber were often grossly undervalued in the agreements, thus massively increasing the profit margin for the middle-men. The deals had not been put out to open tender, and Salye calculated that nearly $100m worth of raw materials disappeared through Putin's committee, and suspected that the total was far greater. Many of the companies disappeared without trace, despite the fact that some were linked to influential St Petersburg figures; one was even registered in the same building as Putin's committee.

Putin later claimed – in the face of documents to the contrary that Salye kept to her death, some signed by Putin himself – that his committee did not issue licences. He also argued that in the chaos that reigned in the early 1990s, the authorities were not prepared for the lawless capitalism of the early post-Soviet days.

Convinced that Putin was at the centre of the scheme and should be made responsible for the huge losses, Salye recommended that he be sacked. But he was protected by his boss, Sobchak, and criminal investigations were soon dropped. In 1996, Salye published more details on the affair in her book Mafia and Corruption (Mafruptsia), and bitterly opposed the support given by many in the democratic movement for Putin as presidential candidate in 2000.

In the late 1990s and early 2000s, the democratic movement was becoming ever more marginal and dangerous. Salye attempted to join forces with the liberal politician Sergei Yushenkov, but disturbed by the fact that their meetings were shadowed by informers, she retired deep into the Russian countryside, to a village near the town of Pskov. In 2003, Yushenkov was shot dead in Moscow, and Salye disappeared from public view.

It was not until 2010 that she reentered the fray, campaigning for democracy in the run-up to the 2011 and 2012 elections. At a time when talk of corruption and cronyism has become commonplace, Salye found she was regarded as the individual whose work on Putin's committee had demonstrated most clearly that corruption goes to the very top.

Salye was said by her friends to have taken very badly Putin's recent election victory. She died of a heart attack, unable to complete her autobiography, but with her life-long companion, Natasha, at her side.

Marina Evgenevna Salye, geologist and politician: born Leningrad 19 October 1934; died Ostrov, Russia 21 March 2012.