 He received a MA in archaeology from Moscow University in 1956, his PhD in archaeology from the Institute of Archaeology, Leningrad in 1965 and a doctorate of historical sciences from Moscow University in 1982.Marshak began his work at the Sogdian ruins, which date from the 5th-8th century, at Panjakent in 1954.He became director of the archaeological expedition in 1978, a position he held until his death.