The Lena Delta, covering an area of about 32 000 square kilometres, is a haven for Arctic wildlife that transforms for five months each summer from frozen tundra to fertile wetlands. The Delta is located at the end of the 4400-km-long course of the Lena River, one of the longest rivers in the world. It is an important breeding ground for many migratory birds and supports diverse populations of fish and several marine mammals.
The largest Delta in the Arctic, the Lena Delta is a complex landscape that has evolved over thousands of years. The Holocene (the geological era extending back from the present to the last 10 000 years) Delta incorporates parts of an older accumulation plain, dating as far back as the mid-to-late Pleistocene Era. Samoylov Island is located in the central southern part of the Lena Delta, close to the Delta apex. Covering an area of 1200 hectares, it is representative of the active and the Holocene part of the Delta, estimated to back about 7000 years.
Various geomorphological levels can be distinguished in the image. The highest terraces in the image are determined by typical wet ice-wedge polygonal tundra with numerous ponds and small lakes, presenting a Mid Holocene deltaic accumulation surface of frozen fluvial permafrost deposits (dark green colours). Two lower levels are formed by Late Holocene fluvial processes (light green colours) and by recent shallow and very active sandbars (whitish colours).
All terraces undergo heavy changes in terms of river bank erosion, island migration or thermal erosion. Another interesting feature is the presence of river ice on some sandbanks in the lower right of the scene, which remained from the spring ri
Contact: Mariangela D'Acunto
European Space Agency