| Autor: |
SMITH, DWIGHT M., GRIFFIN, JOHN J., GOLDBERG, EDWARD D. |
| Zdroj: |
Nature; January 1973, Vol. 241 Issue: 5387 p268-270, 3p |
| Abstrakt: |
A RECORD of prehistoric and historic burning of carbonaceous materials may be found in the elemental carbon contents of the sedimentary columns. The widespread dissemination of such carbon as microcrystalline graphite is indicated by its presence in atmospheric dusts collected over the North Atlantic1and in ice nuclei collected from North Pacific airs2. Its submarine survival over geologic time periods, at least up to millions of years, is suggested by its occurrence in manganese nodules3and in sediments from the Sierra Leone Rise1. But a biologically mediated oxidation of elemental carbon in terrestrial soils has been proposed to explain the gradual disappearance of charcoals originating from forest fires4. The contributions of carbon from industrial activities are also visible and well documented (see, for example, ref. 5). |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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