DATA FROM THE STUDY OF SOIL AND PLANT SAMPLES IN THE REGION OF THE TUNGUS METEOR CRASH OF 1908 (in Russian)
Samples taken at various distances from the epicenter of the 1908 Tungus meteor crash showed an apparent decrease in radioactivity with increasing distance from the point of impact. However, an analysis of the beta energies showed the presence of K/sup 40, Sr/sup 90/-Y/sup 90/ and Ce/sup 144. Pr/sup 144/ Most of the activity was shown to have a half-life of about ome year (the activity of control samples decreased by 30% in 5 momths). It was found that fall-out due to recent nuclear testing contaminated dead wood more heavily than the wood in living trees, and the radioactivity of samples taken under the same conditions showed me relationship to the distance from the epicemter of the meteor crash. However, a study of the radioactivity of growing trees from various regions of the Urals amd Siberia revealed the interesting fact that the annual growth rings im certain trees are a sensitive indicator of the increase in radioactivity and of the time of comtaminatlon of a locale with radioactive fall- out. The activity of the inner rings is due to potassium, and that of the outer rings is due to fission products. Thus, a 60 year old pine tree from the Urals showed a sharp increase in activity im l949 due to fall out from nuclear testimg. A 250 year old pine tree from the region of the Tungus meteor crash of 1908 showed a sharp increase in radioactivity in 1908 as well as in l949. Moreover, the width of the annular growth rings of the trees increased by a factor of five after l908 as compared with previous years. It is concluded that this rapid increase in the rate of growth was a direct result of the Tungus meteor crash. (TTT)
- Research Organization:
- Volga-Urals Branch, All-Union Scientific Research Inst., USSR
- NSA Number:
- NSA-16-001343
- OSTI ID:
- 4821676
- Journal Information:
- Doklady Akad. Nauk S.S.S.R., Journal Name: Doklady Akad. Nauk S.S.S.R. Vol. Vol: 140
- Country of Publication:
- Country unknown/Code not available
- Language:
- Russian
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