Terrestrial Palaeoecology and Global Change

156 Valentin A. Krassilov. Terrestrial Palaeoecology
Archipelago are bordering the larger crustal blocks of the Norwegian, Barents and the
Beaufort – Chukchi seas (Fig. 69). The southern margin of Chukchi block is formed by
the Anyuy thrust belt probably extending to the eastern De Long Islands in the Laptev
Sea (Sokolov et al., 1997) to join the Lomonosov Rise zone as an annular belt of Caledonian
tectonism.
The Neocomian basalts of eastern Svalbard, Franz Josef Land and Barrow, Alaska
(Parker, 1967; Tarakhovsky & Fishman, 1982) attest to a spreading phase synchronized
Fig. 69. Arctic crustal structures interpreted as superposition Palaeozoic and Cretaceous–Eocene patterns of
crustal blocks and their bordering thrust belts: (Ba) Barents block, (Bf) Beaufort block, (Ch) Chukchi block,
(Ka) Kara block, (Nw) Norwegian block. Thrust belts: (AM) Alpha (Mendeleyev) Ridge, (AB) Anyuy Belt,
(BR) Brooks Range, (BINZ) British Isles – Novaya Zemlya belt, (DL) De Longa Rise, (EB) Eureka Sound
belt, (GR) Gakkel Ridge, (LB) Lyakhovkiy belt, (LM) Lomonosov Ridge, (WS) West Svalbard belt. Basins:
(Md) Mackenzie Delta, (SV) Sverdrup. (1) Caledonian structures, those of Lomonosov Rise and eastern De
Longa (thick dashes) supposedly dividing the Palaeozoic blocks, (2) Cretaceous–Tertiary thrust belts, (3)
Foredeep basins, (4) Contours of continental shelf and oceanic rises.