Lena-Angara Plateau should not be confused with Lena Plateau.
| Lena-Angara Plateau Лено-Ангарское плато | |
| Country: | Russia |
| Subdivision2 Type: | Federal subject |
| Subdivision2: | Irkutsk Oblast |
| Highest: | Namai |
| Elevation M: | 1509 |
| Coordinates: | 55.4996°N 106.7035°W |
| Length Km: | 600 |
| Width Km: | 380 |
| Area Km2: | 20000 |
| Range Coordinates: | 55.5°N 105°W |
| Parent: | Central Siberian Plateau |
| Geology: | Limestone, dolomite, sandstone |
| Map: | Russia Irkutsk Oblast |
The Lena-Angara Plateau (Russian: Лено-Ангарское плато),[1] is a plateau in Siberia. Administratively it is in the Irkutsk Oblast, Russian Federation. The plateau is named after the Lena and Angara rivers, of which it forms the watershed. Rivers on the plateau flow mostly in a south–north direction.[2]
The plateau has rich mining areas where iron and copper ores are extracted, as well as rock-salt, talc and mica.[1] The Lena-Angara Plateau is mostly sparsely populated. The biggest settlements are Ust-Kut, Kirensk, Zheleznogorsk-Ilimsky, as well as the villages of Zhigalovo and Kachug. The Bratsk Reservoir is located in the plateau area.[2]
The Lena-Angara Plateau rises in the middle part of Irkutsk Oblast, between the Angara River to the west and the Kirenga River, a tributary of the Lena, to the east. To the northwest it is bound by the Angara Range, to the south by the Angara valley, to the southeast by the Primorsky Range, and to the east by the Baikal Range, beyond which lies Lake Baikal.
To the north the Lena-Angara Plateau merges with the Central Siberian Plateau. It extends roughly for over 600km (400miles) with a maximum width of 380km (240miles).[2] The average height of the plateau surface is 1100m (3,600feet) in the south, decreasing to an average of 500m (1,600feet) in the north. Mountaintops are flat and elevations moderate; the highest point is the Namai,[3] a 1464m (4,803feet) high summit. This same mountain, however, is marked as a 4852feet peak in the E-8 sheet of the Defense Mapping Agency Navigation charts.[4] The same peak is shown as a 1509m (4,951feet) summit in the N-48 sheet of the Soviet Topographic Map.[5]
The plateau is dissected by deep river valleys with average depths ranging between 600m (2,000feet) and 200m (700feet). The upper course of river Lena crosses the plateau roughly from south to north. Its tributaries Kirenga, Ilga, Tutura, Tayura and Kuta join it in the plateau area.[2] [6] The plateau also includes highly developed karst forms such as the Botovskaya Cave.[7]
There are taiga forests made up mostly of larch, spruce and Siberian pine in the higher areas and larch in the river valleys.[1] [6]
