The purpose of the study is to establish a correlation between the source of the final eruptions at Dzotol volcano and the sources of all preceding Late Cenozoic volcanism in the Dariganga field. The homogeneous data set (petrogenic oxides, trace elements, and Pb isotope ratios) obtained for the rocks of the volcanic field indicates the generation of magmatic melts in a single mantle region. The rocks of the final eruptions of the Dzotol volcano reveal, on the one hand, intermediate geochemical characteristics of the Dariganga rock assemblage and, on the other hand, reduced Pb isotopic ratios. We conclude that the sources of the Dariganga volcanic rocks were derived from the deep degassing of protomantle with an age of about 4.47 billion years and were dispersed at the asthenosphere-lithosphere boundary disturbed by transtension. The source of the final melts of Dzotol volcano corresponded in depth to the central part of the magmogenerating region. It manifested a Pb-isotopic protomantle component, which was indicated in the quaternary in the rarely occurring Dariganga rocks.

The sources of Late Cenozoic volcanic rocks marked by fast and slow lower mantle anomalies are of global significance: ASITA, SOPITA, AFITA, and NAITA. ASITA characterizes the melt anomalies of the LOMU-ELMU protomantle of the lower mantle high-velocity Asian sedimentary buttress of the early mantle geodynamic epoch. SOPITA and AFITA are labeled by the plume component of HIMU, which was generated in the low-velocity lower mantle of the South Pacific and Africa during the middle mantle geodynamic epoch, about 2 billion years ago. NAITA marks the processes of generation of the high-velocity lower mantle anomaly of North America in the late geodynamic epoch. Sublithospheric springs of Asia, characterized by a uniform geochemical structure of volcanic rocks of large volcanic areas formed during the evolution of homogeneous protomantle deep reservoirs, are of regional significance. An example is the sources of the Ulankhada-Khannuobin and Abaga-Dariganga volcanic areas, which mark the spatial transition from the LOMU protomantle reservoir of the former to the ELMU protomantle reservoir of the latter. Local sources of volcanoes are manifested in limited volumes of heterogeneous lithosphere melting. An example is the sources of the Wudalianchi volcanic field, where first, in the time interval of 2.5-0.8 Ma, the material of Laoshantou and Gelatsu sources with a single age of 1.88 billion years was manifested, and then, during the spatial and temporal evolution of volcanism in the last 0.6 Ma, the material of these sources was mixed with younger lithospheric material.

The results of determinations of Pb isotope ratios in Late Cenozoic volcanic rocks of the southwestern part of the Baikal rift system along the Kitoi-Baidrag transect are presented. The obtained 207Pb-206Pb estimates of the time of incubation of restite material in the springs agree well with Precambrian dating of ensembles of ancient continental blocks and ophiolite belts exposed on the Earth's surface. Along the transect, the following sources are distinguished: the ancient Gargan block of the Tuva-Mongolian microcontinent (massif) with the Gadean protolith and Archean-Neoproterozoic eventsIn the Baikal-Mongol region, the Khamardaban accretionary-collisional core bounded by the Ilchiro-Tunkinsky and possibly the Dzhidino-Tunkinsky slabs, the Khangai continental domain bounded by the Bayankhongor-Khangai and possibly the Dzhidino-Khangai slabs, and the ancient Baidrag block - a fragment of the Tarbagatai-Dzabkhan microcontinent. Judging from the source dating, the tectonosphere of the early and middle mantle geodynamic epochs in the Baikal-Mongol region included 3 layers: lower (protomantle), middle (mantle evolved), and upper (coro-mantle transition, CMP). In the Hangai continental domain, protoliths of a broad Precambrian source age spectrum were generally modified around 660 Ma. At the end of the Neoproterozoic and in the Early-Middle Phanerozoic, the mantle stabilized against the background of the KMP zone transformations. In the tectonosphere of the latest geodynamic stage, the processes of transformation of three layers: protomantle, mantle evolved and KMP were again activated.

The composition of garnet-bearing and garnet-free associations of deep nodules brought to the surface by Cenozoic and older (Phanerozoic) magmatic melts reconstructs petrologic zones of coroo mantle transition (PZCMP) beneath granulite terranes of cratonic and extracratonic regions. Modern Moho velocity sections only partially coincide with petrological estimates of the replacement of acid-base rocks (belonging to the continental crust) by rocks of predominantly ultrabase composition (forming the continental mantle lithosphere) and are often much deeper than the MTCZ. The depth positions of such zones change with time. Two RT trends have been obtained for the garnet-free association of deep nodules transported by basaltic melts about 13 Ma from the root part of the granulite terrane exposed in the eastern part of the Tunka valley, one of which corresponds to high (up to 120 mW/m₂) rift conductive geotherm, the other crosses low conductive geotherms (falling below the 60 mW/m geotherm) and the other crosses low conductive geotherms (falling below the 60 mW/m₂). The SZCMP has temperatures approximately 200 °C lower than the SZCMP of granulite terranes of eastern Australia, China, and Svalbard. Deep nodules characterise the development of hot transtensia under the rift valley in the cold root part of the East Tunka block with accumulation and discharge of elastic stresses accompanied by significant synkinematic (metasomatic and magmatic) processes in the time interval 18-12 Ma. Transgression was replaced by crustal transpression with inversion uplift of the territory and a probable relative increase in the depth of the Moho interface, determined from P- and S-wave velocities for the modern crust and lithospheric part of the mantle.