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| Titel |
Lena River delta formation during the Holocene |
| VerfasserIn |
D. Bolshiyanov, A. Makarov, L. Savelieva |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1726-4170
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| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 12, no. 2 ; Nr. 12, no. 2 (2015-01-29), S.579-593 |
| Datensatznummer |
250117791
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| Publikation (Nr.) |
 copernicus.org/bg-12-579-2015.pdf |
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| Zusammenfassung |
The Lena River delta, the largest delta of the Arctic Ocean, differs from
other deltas because it consists mainly of organomineral sediments, commonly
called peat, that contain a huge organic carbon reservoir. The analysis of
delta sediment radiocarbon ages showed that they could not have formed as
peat during floodplain bogging; rather, they accumulated when Laptev Sea water level
was high and green mosses and sedges grew and were deposited on the surface
of flooded marshes.
The Lena River delta formed as organomineral masses and layered sediments
accumulated during transgressive phases when sea level rose. In regressive
phases, the islands composed of these sediments and other, more ancient
islands were eroded. Each new sea transgression led to further accumulation
of layered sediments. As a result of alternating transgressive and
regressive phases, the first alluvial-marine terrace formed, consisting of
geological bodies of different ages. Determining the formation age of
different areas of the first terrace and other marine terraces on the coast
allowed the periods of increasing (8000–6000 BP (years before present), 4500–4000, 2500–1500, and 400–200 BP) and decreasing
(5000, 3000, and 500 BP) Laptev Sea levels to be
distinguished in the Lena Delta area. |
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