Deformations and Structural Evolution of Mesozoic Complexes in Western Chukotka

Detailed structural investigations have been carried out in the Pevek district to specify tectonic evolution of the Chukotka mesozoids. The earliest south-verging folds F1 formed in Triassic rocks at the first deformation stage DI. These structures are overlapped by the northern-verging folds F₂ and overthrusts pertain to the second deformation stage DII. Folding structures F₁ and F₂ were deformed by shear folds F₃, completing stage DII. The DI and DII structures are complicated by roughly NS-trending normal faults marking deformation stage DIII. It has been established that DI is related to the onset of opening of the Amerasian Basin in the Early Jurassic, or, alternatively, to the later accretion of the Kulpolnei ensimatic arc toward the Chukotka microcontinent. DII marks the collision of Siberia and the Chukotka microcontinent in the Late Neocomian. Normal faulting under the roughly E–W-trending extension during DIII is likely related to rift opening of the Podvodnikov and Makarov–Toll basins in the deep Amerasian Basin. Formation of the Okhotsk–Chukotka volcanoplutonic belt completed the structural evolution of the studied region.     

Tectonic Position of the South Anyui Suture

Geotectonics - The South Anyui Fold System was formed at the end of the Early Cretaceous at the site of a closed oceanic basin as a result of the collision of the Chukotka microcontinent with the...     

New Data on Volcanism of the Central Chukotka Segment of the Okhotsk–Chukotka Volcanogenic Belt

Doklady Earth Sciences - New geochronological and geochemical data on the age and composition of undifferentiated Cretaceous volcanics from the Palyavaam River basin, Central Chukotka region, are...     

Paleotectonic Setting of the Accumulation of Middle Jurassic Deposits in the Northeastern Flange of the Nagondzha Terraine (Ulakhan-Sis Ridge)

Doklady Earth Sciences - The age of the Middle Jurassic deposits of the Ulakhan-Sis Range is corrected to the Bajocian–Middle Bathonian. Three terrigenous units are identified that formed at...     

Structural evolution of Mesozoic complexes in Western Chukotka

Detailed structural investigations were carried out in the Pevek area in order to verify the tectonic evolution of the Mesozoic thrust and fold belt in Chukotka. South-vergent F₁ folds in Triassic rocks were proved to be the earliest structures formed during the first deformation stage DI. These structures were deformed by north-vergent folds F₂ that were formed during the second deformation stage DII. North-vergent folds are the main structures of the Jurassic–Lower Cretaceous complex. The fold structures of the first two stages are deformed by shear folds F₃ finishing the stage DII. All these structures are deformed by submeridionally trending normal faults referred to the deformation stage DIII.     

Erratum to: Suprasubduction Volcanism of Chukotka Terrane in the Late Jurassic–Early Cretaceous (Arctic Region,Russia)

Geotectonics - erratum     

Roles of Postcollisional Granitoids and Aptian–Albian Extension in Tectonic Evolution of Mesozoic Structures on Chukchi Peninsula,Northeastern Russia

Doklady Earth Sciences - New U–Pb SIMS zircon datings from granitoid plutons and dikes of Western Chukotka, together with data obtained earlier, confirm that postcollisional granitoid...     

Supraproduction Volcanism of Chukotka Terrane in the Late Jurassic–Early Cretaceous (Arctic Region,Russia)

Geotectonics - The age and geodynamic position of the volcanic source of the Upper Jurassic–Lower Cretaceous deposits of Western Chukotka were determined. Products of synchronous volcanism...