Russian scientists have found out that recent episodes of accelerated accumulation of radioactive lead-210 atoms in bottom sediments in the Laptev Sea are associated with massive forest fires that have occurred in Siberia, Yakutia and the Far East in the last fifty years, the press service of the Russian Science Foundation reports.
"The increase in radioactivity of marine sediments in certain periods is due to forest fires in Siberia, Yakutia and the Far East. Mosses, lichens and peat are powerful accumulators of radioactive isotopes of lead. During combustion, this element is released into the atmosphere of the Northern Hemisphere, and then enters the sea, which causes fluctuations in the activity of lead in bottom sediments," explained Valery Rusakov, a leading researcher at the Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences.
Rusakov and his colleagues came to this conclusion by studying which natural factors influence the rate of accumulation of unstable lead-210 in soil sediments at the bottom of the seas.
This short-lived isotope of lead with a half-life of about 22 years is used by geologists to determine the age of sediments, their accumulation rate and other parameters reflecting the history of their formation, nauka.tass.ru writes.
Alex Shishlo for Rough&Polished
