Geochemical and geochronological constraints on distinct Early-Neoproterozoic and Cambrian accretionary events along southern margin of the Baydrag Continent in western Mongolia

Buriánek, David; Schulmann, Karel; Hrdličková, Kristýna; Hanžl, Pavel; Janoušek, Vojtěch; Gerdes, Axel; Lexa, Ondrej

doi:10.1016/j.gr.2016.09.008

Cited by 66 publications

(64 citation statements)

References 81 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Indeed, neighboring Neoproterozoic‐early Paleozoic arc‐related complexes of the Lake Zone and its adjacent Zavhan and Baydrag blocks may have provided an important contribution to the studied Ordovician sedimentary basin. It is well documented that the Mongolian Precambrian blocks underwent multiple magmatic and metamorphic events dated at 2.8 Ga to 0.9 Ga (Bold et al, ; Buriánek et al, ; Demoux, Kröner, Badarch, et al, ; Kozakov et al, ; Kröner et al, ). The widely reported Neoproterozoic magmatic rocks correlated with subsequent magmatic event yielded ages of 750–610 Ma (Dijkstra et al, ; Kuzmichev et al, ; Levashova et al, ; Osozawa et al, ; Sal'nikova et al, ).…”

Section: Discussionmentioning

confidence: 99%

“…It was recently shown that part of the Baydrag basement became tectonically interdigitated with high‐pressure metamorphic rocks during NE directed (in recent coordinates) thrusting of Neoproterozoic ophiolites over its passive margin at circa 540 Ma (Lehmann et al, ; Štípská et al, ). These ophiolites were interpreted as being derived from Neoproterozoic marginal basins, oceanic arcs, and accretionary wedges soon before (Buriánek et al, ; Khain et al, ). Such a configuration implies a Neoproterozoic tectonic regime driven by a SW dipping subduction.…”

Section: Discussionmentioning

confidence: 99%

“…Such a configuration implies a Neoproterozoic tectonic regime driven by a SW dipping subduction. On the other hand, the emplacement of the Cambrian Ikh‐Mongol magmatic arc and the development of a Cambrian‐Ordovician turbidite basin showing a generally southward younging (e.g., Tomurtogoo, ) favor NE dipping early Paleozoic subduction beneath the Precambrian continental blocks (Buriánek et al, ; Janoušek et al, ). In other words, we infer a reversal of the subduction system from SW to NE dipping during the early Paleozoic in the present coordinates.…”

Section: Discussionmentioning

confidence: 99%

“…The Zavhan‐Baydrag and adjacent units show many comparable features with the TAO, in particular concerning the following three major aspects (Figure ): (1) A rifted passive margin sequence developed in the TAO at circa 600 Ma (Crawford et al, ; Direen & Crawford, ) when the southwestern Mongolian Precambrian blocks were characterized by the development of Ediacaran epicontinental basins and rifted passive margins (Bold et al, ; Khain et al, ; Kuzmichev, ). This was followed by thrusting of island arc fragments over the Australian passive margin at circa 520 Ma (Foster et al, ), almost simultaneous with the emplacement of high‐pressure rocks and Neoproterozoic ophiolites on the margin of the Baydrag continent (Štípská et al, ); (2) Continuously advancing Pacific subduction was responsible for the Delamerian orogenic phase in the TAO and widespread Andean‐type arc magmatism culminating at 505–495 Ma (Cawood & Buchan, ), coeval with the main orogenic cycle and active margin magmatism at 520–490 Ma in Mongolia (Buriánek et al, ; Janoušek et al, ); (3) Pacific plate rollback at 508–460 Ma produced a > 1,000 km wide back‐arc basin in the Australian sector that became the basement for the Lachlan turbidites (Foster & Gray, ), again contemporaneous with the formation of the giant turbidite basin in the Mongolian and Chinese Altai. We compared detrital zircon age patterns of the Mongolian Ordovician turbiditic sediments with those of the Antarctic and Australian sectors of the TAO (Figure ).…”

Section: Discussionmentioning

confidence: 99%

“…Recent studies reveal the presence of Late Cambrian‐Early Ordovician arc‐type granitoid magmatism that affected both the southern border of the Precambrian continental blocks and the Lake Zone (Buriánek et al, ; Janoušek et al, ; Kozakov et al, ; Kröner et al, ; Soejono et al, ), forming a giant magmatic arc, named Ikh‐Mongol arc system in western central Mongolia (Janoušek et al, ). Abundant granitoids dated as Silurian‐Devonian intruded the Altai Zone mainly in the south (e.g., Wang et al, ; Yuan et al, ), coevally with the formation of migmatite‐magmatite domes (Jiang et al, ).…”

Section: Geological Frameworkmentioning

confidence: 99%

See 4 more Smart Citations

Neoproterozoic‐Early Paleozoic Peri‐Pacific Accretionary Evolution of the Mongolian Collage System: Insights From Geochemical and U‐Pb Zircon Data From the Ordovician Sedimentary Wedge in the Mongolian Altai

et al. 2017

View full text Add to dashboard Cite

Neoproterozoic to early Paleozoic accretionary processes of the Central Asian Orogenic Belt have been evaluated so far mainly using the geology of ophiolites and/or magmatic arcs. Thus, the knowledge of the nature and evolution of associated sedimentary prisms remains fragmentary. We carried out an integrated geological, geochemical, and zircon U‐Pb geochronological study on a giant Ordovician metasedimentary succession of the Mongolian Altai Mountains. This succession is characterized by dominant terrigenous components mixed with volcanogenic material. It is chemically immature, compositionally analogous to graywacke, and marked by significant input of felsic to intermediate arc components, pointing to an active continental margin depositional setting. Detrital zircon U‐Pb ages suggest a source dominated by products of early Paleozoic magmatism prevailing during the Cambrian‐Ordovician and culminating at circa 500 Ma. We propose that the Ordovician succession forms an “Altai sedimentary wedge,” the evolution of which can be linked to the geodynamics of the margins of the Mongolian Precambrian Zavhan‐Baydrag blocks. This involved subduction reversal from southward subduction of a passive continental margin (Early Cambrian) to the development of the “Ikh‐Mongol Magmatic Arc System” and the giant Altai sedimentary wedge above a north dipping subduction zone (Late Cambrian‐Ordovician). Such a dynamic process resembles the tectonic evolution of the peri‐Pacific accretionary Terra Australis Orogen. A new model reconciling the Baikalian metamorphic belt along the southern Siberian Craton with peri‐Pacific Altai accretionary systems fringing the Mongolian microcontinents is proposed to explain the Cambro‐Ordovician geodynamic evolution of the Mongolian collage system.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Geological Frameworkmentioning

confidence: 99%

See 3 more Smart Citations

Neoproterozoic‐Early Paleozoic Peri‐Pacific Accretionary Evolution of the Mongolian Collage System: Insights From Geochemical and U‐Pb Zircon Data From the Ordovician Sedimentary Wedge in the Mongolian Altai

et al. 2017

View full text Add to dashboard Cite

show abstract

The Early Palaeozoic mega‐thrusting of the Gondwana‐derived Altay–Lake zone in western Mongolia: Implications for the development of the Central Asian Orogenic Belt and Paleo‐Asian Ocean evolution

Khukhuudei

Kusky

Otgonbayar³

et al. 2020

Geological Journal

View full text Add to dashboard Cite

The position of structures of Mongolia during Rodinia break‐up and Paleo‐Asian Ocean opening is debatable, and reconstructions between them are poorly known. In this paper, we apply an integrated approach to the not widely known yet distinctive structure (ribbon‐like) of the Lake and Mongolian Altay zones in western Mongolia, relating these with the surrounding Tuva–Mongolian and central Mongolian microcontinents (CMMs) development within the Central Asian Orogenic Belt (CAOB) and Paleo‐Asian Ocean evolution. We present a summary of the Neoproterozoic–early Palaeozoic tectonic development of western Mongolia and the CAOB and suggest a new comprehensive model for its evolution. The Lake zone of Mongolia is a major zone of ophiolite and arc complexes within the CAOB. The main sections of ophiolites are located along the west margin, bordering with Precambrian crystalline basement of the CMM. The ophiolites are distributed from north to south and have been dated to have similar ages. A classic oceanic plate stratigraphy section is preserved in the Lake zone. Serpentinite mélange and other volcanogenic‐terrigenous assemblages from the Lake zone are characterized by a system of nappe sheets thrust over the Dzavkhan block of the CMM. The ribbon‐like structure that the southern part of the Altay–Lake zone preserves at present provides an explanation for the development between the Gondwana‐derived microcontinent and Paleo‐Asian Ocean. During the pre‐Neoproterozoic, convergence accretion between Siberia and the CMM formed the Tuva–Mongolian belt, which later converted to the Altay–Lake collision zone associated with the thrusting of its eastern margin. All well‐known ophiolites of western Mongolia (Agardag, Khantayshir, and Dariv) as well as ophiolites of the Erdene Uul area mostly correspond to an “open‐ocean” phase with drifting microcontinents between 655 and 540 Ma or Neoproterozoic. In the early Neoproterozoic, the Altay peninsula‐like ribbon microcontinent after rifting of East Gondwana gradually drifted to Siberia. In this time, the east margin of the Paleo‐Asian Ocean was developed as a passive margin with the Dzavkhan Block. The Paleo‐Asian ocean plate simultaneously drifted to the CMM, whereas the Altay microcontinent moved into Siberia‐CMM. In middle‐upper Neoproterozoic times, the eastern part of the Paleo‐Asian ocean plate was thrusted over the CMM, obducting ophiolites (e.g., Tas Khairkhan), in the early Cambrian time, an oceanic spreading centre (?) of the Paleo‐Asian Ocean reached the CMM and stopped obduction. In the Neoproterozoic, the west margin of the Paleo‐Asian Ocean was developed as an active continental margin, with subduction under the Gondwana‐derived microcontinent. In the early Cambrian, there was significant subduction rollback and accretion of seamounts (Turgen). Later, in middle Cambrian–early Ordovician times, a large turbidite sequence was deposited in Altay. During the Devonian to Carboniferous, the Paleo‐Asian Ocean was preserved as a remnant ocean or big sea (Lake zone), accumulating ...

show abstract

Did the circum-Rodinia subduction trigger the Neoproterozoic rifting along the Congo–Kalahari Craton margin?

Konopásek

Janoušek

Oyhantçabal

et al. 2017

Int J Earth Sci (Geol Rundsch)

View full text Add to dashboard Cite

Geochemical and geochronological constraints on distinct Early-Neoproterozoic and Cambrian accretionary events along southern margin of the Baydrag Continent in western Mongolia

Cited by 66 publications

References 81 publications

Neoproterozoic‐Early Paleozoic Peri‐Pacific Accretionary Evolution of the Mongolian Collage System: Insights From Geochemical and U‐Pb Zircon Data From the Ordovician Sedimentary Wedge in the Mongolian Altai

Neoproterozoic‐Early Paleozoic Peri‐Pacific Accretionary Evolution of the Mongolian Collage System: Insights From Geochemical and U‐Pb Zircon Data From the Ordovician Sedimentary Wedge in the Mongolian Altai

The Early Palaeozoic mega‐thrusting of the Gondwana‐derived Altay–Lake zone in western Mongolia: Implications for the development of the Central Asian Orogenic Belt and Paleo‐Asian Ocean evolution

Did the circum-Rodinia subduction trigger the Neoproterozoic rifting along the Congo–Kalahari Craton margin?

Contact Info

Product

Resources

About