**5. Geodynamic evolution of the Bureya-Jiamusi superterrane**

fact, up to our time—260 years ago (bass Nemarhe river—mineral spring Udalyanchi, China). Herewith, typical adakites were formed in the frames of the southern flank of the superterrane—on the border with the orogenic belt of Wundurmiao [2]. The age of adakitic rocks is 55 Myr. All the following magmatites (less than 20 Myr) correlate with the intraplate forma-

Ideas about the location of the Bureya-Jiamusi superterrane in the Late Mesozoic-Cenozoic are quite various. Thus, according to [33] the joining of Bureya-Jiamusi superterrane to Argun superterrane (through South Mongolian-Khingan belt or Sungliao block according to the views of the Chinese geologists) occurred in the second half of Paleozoic. It accreted to the Chinese-Korean craton in late Permian [46]. And later, being a part of Amur plate, together with the Chinese-Korean craton, superterrane moved north and accreted to Siberian platform, forming Mongol-Okhotsk orogenic belt and provoking closure of Mongol-Okhotsk basin. Different authors suggest various time stages of the process of the basin closure: in the early

It is known that the union of large geological objects, as a rule, is accompanied (fixed) by magmatic manifestations. The following stages of volcanic activity are set for the northern flanks of the Argun superterrane and the South Mongolian-Khingan (Sunglao) orogenic belt: 147– 138 Myr—volcano-plutonic complex of adakite granites—trachyriolites; 140–122 Myr—differentiated calc-alkaline volcano-plutonic complex; 119–97 Myr—bimodal volcano-plutonic complex; 94-cognac (88?)—absarokite-trachyandesite intraplate [3, 6, 37]. Absolutely other age sequence of Bureya-Jiamusi superterrane magmatic activity is noted in late Mesozoic.

In the author's opinion, the final closure of the Mongolian-Okhotsk basin occurred in the interval 119–97 Myr and was accompanied by the formation of bimodal volcano-plutonic complexes in the frames of the Mongolo-Okhotsk belt [3]. So far, it can be stated that an entirely different age sequence of magmatic activity is noted in the late Mesozoic within the Bureya-Jiamusi superterrane. And the magmatites formed at the same time have disparate material characteristics with late Mesozoic volcanites of the Argun superterrane and the South Mongolian orogenic belt. The fact that the closure of Mongol-Okhotsk orogenic belt was accompanied by the formation of riftogenic structures in its frames, made by the bimodal complexes formations, is confirmed by the evolution of the western flank of the Mongol-Okhotsk orogenic belt [1]. The absence of bimodal complexes in the territory of Bureya-Jiamusi superterrane [4, 5] can be an evidence of the fact that the studied superterrane did not participate in the closure of the Mongol-Okhotsk basin, that this geological object represented an independent structure in the late Mesozoic.

The idea of the tectonic boundary of the Bureya-Jiamusi superterrane with the Badzhal and Honshu-Sikhotealin orogenic belts is almost unambiguous for all authors. And the ideas of the researchers of the eastern structures and the Bureya-Jiamusi superterrane collision time,

which fits into the interval 155–125 Myr [16], are close.

tions by their geochemical characteristics.

38 Tectonics - Problems of Regional Settings

**4. Tectonic position of the Bureya-Jiamusi superterrane**

Cretaceous [32], in the Late Jurassic [46], or at the end of the Paleozoic [26].

The Bureya-Jiamusi superterrane tectonic development scheme for the territory of China was developed back in 1994 by Liu Zhaojun with co-authors [47]. According to this scheme, the stretching prevailed in the region in late Jurassic-early Chalk. It was triggered by changes in the movement of the Izanagi ocean plate. As a result, rift-like structures were formed about 135 Myr ago. These structures were filled with of coal-bearing precipitates and volcanites of acid composition. In the territory of Russia, within the Bureya-Jiamusi superterrane, a similar volcanic complex with an age of magmatic component of 136–135 Myr [4, 37] is formed during this period. The territory of Bureya-Jiamusi superterrane represented a passive continental margin and, probably, was at rest approximately 135–120 Myr. According to palinspastic reconstructions (Bretshtein and Klimov [16] and Didenko with coauthors [9]), Bureya-Jiamusi superterrane was an independent geological body during this period. It drifted on the Izanagi oceanic plate in the northwestern (close to northern) direction with a speed of 30–20 cm per year [23]. Magmatic activity occurred throughout the territory of Bureya-Jiamusi superterrane during the interval of 120–99 Myr actually [4, 5, 30, 38].

According to the palinspastic data of Bretshtein and Klimov [16], the Bureya-Jiamusi superterrane accretion to the Badzhal terrain occurred in post-Jurassic. It was shown that the formation of volcanites with geochemical marks of the suprasubduction type took place 120–105 Myr [2, 4, 5, 7]. Based on the data, it can be assumed that the subduction processes covered almost the entire territory of the Bureya-Jiamusi superterrane during this period. We can consider the following as one of the possible tectonic scenarios: subduction processes are caused by the displacement of a younger and, therefore, more plastic Badzhal terrain to older formations of the Bureya-Jiamusi superterrane, which has more power and rigidity.

What was the cause of this? According to paleomagnetic definitions [23], the Izanagi plate reversed its direction from north-west to northeast 119 Myr. And although the angle of rotation was insignificant, and the speed changed by only 0.6 cm per year (from 21.1 to 20.5 cm/year), it could be enough for the interaction of these geological objects to occur. Proceeding from such a tectonic scenario, the next stage of magmatic activity will be more understandable. Catastrophic events that were accompanied by the formation of an intraplate volcano-plutonic complex of acidic-alkaline rocks at the contact of Bureya-Jiamusi superterrane and Badzhal terrain occurred about 101–99 Myr [8, 36]. Therefore, it is assumed as the most likely scenario, that during the subduction process a sharp break (breakage) and a plunge of the slab of Badzhal terrain into the asthenospheric "window" occurred. This was, naturally, accompanied by an active and short-term formation of the rocks of the intraplate volcano-plutonic complex [4, 8, 36] (**Figure 3**).

According to paleomagnetic data, for the main tectonic units of the Far East south [16] in the Jurassic-Neogenic interval, the Bureya-Jiamusi superterrane was at a very considerable distance from the continental margin of Asia. Similar research works [18] prove that the width of the Mongolo-Okhotsk paleobasin in the late Jurassic was about 3000 km. Paleomagnetic

Most likely, the drift of a collage of terrains, now, according to the motion of the ocean plate Izanagi, occurred in this period. The Izanagi plate moved to the northwest at a speed of 23.5 cm per year, and then in the western direction (85–74 Myr) at a speed of 20.2 cm per year [23] during 100–85 Myr time period. It can be assumed that this movement continued until the final joining of the Bureya-Jiamusi superterrane to the eastern edge of the Asian continent. If we accept the fact that tectonic rearrangements are usually accompanied by magmatic events, it can be stated that its accession to the east of the Asian continent took place approximately 56–55 Myr. This is confirmed by the appearance of adakite fields in the accretion place of the Bureya-Jiamusi superterrane and the orogenic belt of Wundurmiao and the China-Korean plateau (**Figure 1**) aged 55.5 Myr [2]. Mesozoic adakite granitoids and their volcanic analogs are identified and studied during the last decade in such regions as Romania, Turkey, Korea, East, and Southwest China. According to the generalized analysis of petro- and geochemical characteristics, these rocks are associ-

Bureya-Jiamusi Superterrane: Tectonic and Geodynamic Processes in Late Mesozoic - Cenozoic

http://dx.doi.org/10.5772/intechopen.72538

41

Complex tectonic rearrangements comparable to the transformational situation of the Californian type occurred when the Bureya-Jiamusi superterrane collided with the continental margin of Asia [15]. Surely, the subduction moments were present among the processes accompanying the transformational interaction of the two continental margins. And farther, the pulsation outflow of lavas of the main-medium composition with increased alkalinity and geochemical characteristics of intraplate magmatism [4] takes place actually up to now.

All the suggested geodynamic reconstructions of the studied region take into account the interdependence between North-Asian and China-Korea plates and plates of the Pacific basin oceanic crust [16]. The suggested work attempts to show the dependence of the evolution of the Bureya-Jiamusi superterrane on the surrounding geological objects in the late Cretaceous-Cenozoic interval. As a result of the analysis of the original and extensive literature, it is suggested that magmatic activity—its manifestations and activity changes—in the Bureya-Jiamusi superterrane territory correlates quite well with the geodynamic events occurring in the late Mesozoic-Cenozoic, not only on the continental margin of Asia but also within the evolution of oceanic plates of the Pacific basin (plate Izanagi). Comparison of the time stages, material composition, and tectonic positions of the Bureya-Jiamusi superterrane in this time

Laboratory of Geodynamic and Petrogenesis, Institute of Geology and Nature Management,

interval indicates its belonging to the structures of the Pacific mobile belt.

Address all correspondence to: derbeko@mail.ru

ated with subduction processes [13].

**6. Conclusion**

**Author details**

Derbeko Inna

FEB RAS, Russia

**Figure 3.** Hypothetical scheme of the spatial position of the Bureya-Jiamusi superterrane, compiled from original data and materials [2, 12, 25, 31, 39, 43]. Areas of distribution of rocks of late Mesozoic volcano-plutonic complexes: (1–2) differentiated and bimodal: mainly plutonic (1), mainly volcanic (2); volcano-plutonic complexes of Bureya-Jiamusi superterrane; (3–5) with the late Jurassic age—135 Myr (3), 120–105 Myr (4), 101–99 Myr (5). The boundaries of superterrane (6–7): subduction boundaries (6), transforming boundaries (7). Age of the magmatic rocks (8). Other tectonic boundaries (9).

determinations for the terrains of the Sikhote-Alin orogenic belt structures bordering the superterrane from the east [9, 28, 29] showed that they were much more south of the 30th parallel 123 ± 22 Myr. All this confirms the assumption that Bureya-Jiamusi superterrane was located at a considerable distance from its current location and was an independent geological object in late Mesozoic. Any magmatic activity in the Bureya-Jiamusi superterrane is absent (not established) in the interval 99–56 Myr.

Most likely, the drift of a collage of terrains, now, according to the motion of the ocean plate Izanagi, occurred in this period. The Izanagi plate moved to the northwest at a speed of 23.5 cm per year, and then in the western direction (85–74 Myr) at a speed of 20.2 cm per year [23] during 100–85 Myr time period. It can be assumed that this movement continued until the final joining of the Bureya-Jiamusi superterrane to the eastern edge of the Asian continent. If we accept the fact that tectonic rearrangements are usually accompanied by magmatic events, it can be stated that its accession to the east of the Asian continent took place approximately 56–55 Myr. This is confirmed by the appearance of adakite fields in the accretion place of the Bureya-Jiamusi superterrane and the orogenic belt of Wundurmiao and the China-Korean plateau (**Figure 1**) aged 55.5 Myr [2].

Mesozoic adakite granitoids and their volcanic analogs are identified and studied during the last decade in such regions as Romania, Turkey, Korea, East, and Southwest China. According to the generalized analysis of petro- and geochemical characteristics, these rocks are associated with subduction processes [13].

Complex tectonic rearrangements comparable to the transformational situation of the Californian type occurred when the Bureya-Jiamusi superterrane collided with the continental margin of Asia [15]. Surely, the subduction moments were present among the processes accompanying the transformational interaction of the two continental margins. And farther, the pulsation outflow of lavas of the main-medium composition with increased alkalinity and geochemical characteristics of intraplate magmatism [4] takes place actually up to now.
