... been preserved in the fold-andthrust structure of Central Transbaikalia in the interfluve of rivers Khilok and Chikoi as an intensely deformed fragment of relatively weakly metamorphosed volcanic rocks of basalt and andesite composition ( Kozubova, 1967 ; Sizykh, 1967 ; Gordienko, 2021 ). Here we...

... continental features of Transbaikalia ( Fig. 1 ). It is a wide (20–30 km) graben-synclinal structure complicated by the Motnin and other smaller intratrough horsts. The trough extends in a sublatitudinal direction for more than 150 km along the middle course of the Khilok River. In the north it borders...

... of poles (for this study of hand specimens) used in statistics. The Badin Formation of Late Jurassic (the fifth region of sampling) is widespread in the Khilok-Uda interfluve, in the basin of the Zun-Nemetei, Yamnaya, Ubugutta, and Ortinka rivers. The rocks of the Badin Formation make up chiefly...

... of the Hentiyn–Daurian regional igneous province. The Western Transbaikalia segment, within which a large part of the MT profile is located, extends from the confluence of the Selenga and Dzhida Rivers through the basin of the Uda, Tunga, and Khilok Rivers to the upper reaches of the Vitim River and has a length...

...Fig. 4. Classification diagrams for pyroxenes ( a ), amphiboles ( b ), and biotites ( c ) from West Transbaikalian CD rocks. Kharitonovo massif: 1 , basic and 2 , salic components of dikes; Ust’-Khilok massif: 3 , basic and 4 , salic components of dikes at the Zhirim and Ust’-Khilok sites; 5...

...D.V. Metelkin; I.V. Gordienko; Xixi Zhao New paleomagnetic data have been obtained from Early Cretaceous volcanosedimentary sections of the Chikoi-Khilok, Borgoi, and Uda depressions of Transbaikalia. A paleomagnetic pole has been positioned to satisfy the modern criteria of reliability so...

.... The most complete cross section of the Khilok Formation is outcropped in the center of the Uda depression, along the Egita River valley. Volcanics produce a vast lava field, which consists of some gently lying flows of trachybasalts and trachyandesite basalts. The lower part of section is dominated...

... batholith and the beginning of large-scale alkali-granitoid magmatism. Three granitoid plutons of the Zaza suite (U1ekchin, Shaluta, and Baisa) and two syenite and granite plutons of the Lower-Selenga suite (Ust’-Khilok and Nadeino) were studied. It was established that the Zaza suite is most likely of Late...

... – – 5.4 – 59 Ust’-Khilok massif, Selenga River B343 Syenite 7.42 – 4.99 – 60 Ust’-Khilok massif, Selenga River B341 Syenite – – 4.8 – 61 Ust’-Khilok massif, Selenga River B337 Syenite 6.52 – 3.4 – 62 Ust’-Khilok massif, Selenga River B700-10 Syenite – – 4.39...

...). They also exhibit signs of plastic deformation of basic-rock material suggesting that it was a viscous liquid (see the lower part of A). Composite basic-rock-leucogranite dikes occur within the Ust’-Khilok Massif 8 to 12 km in width, extending along the Selenga River for nearly 60 km (see Fig. 1...

... Authors’ data 3 Turka gabbro–monzonite massif, monzodiorite Left bank of the upper reaches of the Turka River U–Pb 514.6 ± 7.2 Authors’ data Composite dike in the Ust’-Khilok monzonite–quartz syenite massif (Zhirim site) Basic component U–Pb ** 282.45.6 Authors’ data Salic component...

... to a system of subparallel grabens, horsts, and related subalkalic volcanic associations. These manifestations of magmatism are concentrated within a NE-trending strip more than 1000 km long and up to 200 km wide. It extends from the Dzhida, Selenga, Uda, Tugnui, and Khilok River basins in the west...

... follow DSS profiles across the Baikal rift (Ust’-Uda—Khilok) and along the northeastern flank of the rift system (Ust’-Kut—Nizhneangarsk—Chara). Gravity instability is produced by a zone of anomalous mantle and the 10–12 km deep Baikal basin which have low elastic moduli and density. We estimated...