| Abstract: | New data on the geology and tectonics of the main structural elements of the East Transbaikalian segment of the Central Asian
Foldbelt are discussed. Correlation charts of the main stratified and igneous complexes are compiled. The rocks of the Baikal-Patom
and Baikal-Muya belts, as well as the Barguzin-Vitim Superterrane, are characterized by new Nd isotopic data, which have allowed
us to establish the sources of these rocks, to separate isotopic provinces, and to distinguish two stages of crust-forming
processes: the Early Baikalian (1.0–0.8 Ga) and the Late Baikalian (0.70–0.62 Ga). The Early Baikalian crust was formed in
relatively narrow and spatially isolated troughs of the Baikal-Muya Belt and probably in the Amalat Terrane, whereas the Late
Baikalian continental crust was formed and reworked in the Karalon-Mamakan, Yana, and Katera-Uakit zones of the Baikal-Muya
Belt. The Baikal-Patom Belt and most of the Anamakit-Muya Zone in the Baikal-Muya Belt are characterized by remobilization
of the Early Precambrian continental crust and by a subordinate role of Late Riphean juvenile sources. Reworking of the mixed
Late Riphean and Early Precambrian crustal sources is typical of the Barguzin-Vitim Superterrane. The origination and evolution
of the continental crust in the studied region are considered in light of new data; alternative versions of paleogedynamic
reconstructions are discussed. |
