Mappable features of mélanges derived from Ocean Plate Stratigraphy in the Jurassic accretionary complexes of Mino and Chichibu terranes in Southwest Japan

Wakita, Koji

doi:10.1016/j.tecto.2011.10.019

Cited by 90 publications

(54 citation statements)

References 28 publications

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“…It is well known that mélanges can form in a variety of tectonic settings by fragmentation and mixing processes, and the different modes of origin of mélanges lead to different compositions and structures (Festa et al, ; Onishi & Kimura, ; Wakabayashi & Dilek, ; Wakita et al, , ). By large scale mapping, geochemical and provenance analysis, we obtained a detailed description of the composition and structure of the Southern Kangurtag mélange, which will contribute to an improved understanding of its tectonic setting.…”

Section: Discussionmentioning

confidence: 99%

Composition, Provenance, and Tectonic Setting of the Southern Kangurtag Accretionary Complex in the Eastern Tianshan, NW China: Implications for the Late Paleozoic Evolution of the North Tianshan Ocean

et al. 2019

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The Kangurtag belt in the Eastern Tianshan, connecting the Dananhu Arc with the Central Tianshan Arc, contains diagnostic rocks of accretionary origin, and thus provides key information about the evolution of the North Tianshan Ocean. The Southern Kangurtag belt is composed of two types of mélange. Type I mélange consists of Enriched Mid‐Ocean Ridge Basalt‐type pillow basalts, draped by biohermal limestones and carbonate‐siliceous sediments of a slope facies, and siliceous argillites from a hemipelagic‐pelagic environment that together make up a seamount assemblage. In Type II mélange, Normal Mid‐Ocean Ridge Basalt and ribbon cherts were dismembered and entrained in a clastic matrix, showing a “block‐in‐matrix” structure. Detrital zircons of four sandstones from Devonian and Carboniferous strata within the mélanges have a predominant age population of 410–430 Ma and a distinct Proterozoic cluster around 1.4–1.6 Ga. The εHf(t) values of Phanerozoic zircons range from −25.1 to +8.6. Such age patterns, typical of the Central Tianshan Arc, and the Hf isotopic data indicate that these sedimentary successions were deposited on the northern margin of the Central Tianshan Arc. The youngest detrital zircon age of 317 Ma provides an upper limit for the time of formation of the Southern Kangurtag accretionary complex. Therefore, we suggest that the Southern Kangurtag belt comprises an accretionary complex that developed during southward subduction of the North Tianshan Ocean beneath the Central Tianshan Arc. This subduction began in the Early Ordovician and may have lasted until the Late Carboniferous–Permian.

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Section: Discussionmentioning

confidence: 99%

Composition, Provenance, and Tectonic Setting of the Southern Kangurtag Accretionary Complex in the Eastern Tianshan, NW China: Implications for the Late Paleozoic Evolution of the North Tianshan Ocean

et al. 2019

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“…OPS is defined as "the sequence of igneous basement representing oceanic lithosphere, together with its carapace of sedimentary and igneous rocks that were deposited on the sea floor as the underlying oceanic basement moves from a mid ocean ridge to a deep-sea trench" (Kusky et al, 2011;Kusky et al, 2013;Kusky, Windley & Polat, 2018). The classic OPS section is represented by mid-ocean ridge basalt-chert (limestone)-hemipelagic shale/ mudstone-sandstone/ conglomerate/ turbidite (Maruyama, Kawai, & Windley, 2010), but there are many possible variations regarding with an idealized model of OPS reconstruction (Kusky et al, 2013;Kusky, Windley & Polat, 2018;Maruyama et al, 2010;Wakita, 2012;Wakita & Metcalfe, 2005), particularly, different types of oceanic basement that the sedimentary carapace gets deposited upon, to the types of early sediments (such as carbonates) and to the variations acquired in the younger sediments as the oceanic basement approaches different types of convergent margins (Kusky et al, 2013;Kusky, Windley & Polat, 2018).…”

Section: Is the Lake Zone With Ops A Remnant Part From The Paleo-asmentioning

confidence: 99%

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

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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 ...

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“…The pyroclastic rocks are mainly composed of ash and glassy lithic lapillis ( Figure 6F). Convoluted mudstones are sometimes included in the pyroclastic beds ( Figure 6G), suggesting they were resulted from rapid turbulent flow of syn-volcanic pyroclastic materials, which were capable of shearing off substrate muddy sediments [44]. The occurrence of pyroclastic interbeds is distinctive from the subunits described above and indicates that volcanic eruptions were possibly intensified in the provenance area.…”

Section: Mugagangri Group (Mg)mentioning

confidence: 93%

Mapping Lithologic Components of Ophiolitic Mélanges Based on ASTER Spectral Analysis: A Case Study from the Bangong-Nujiang Suture Zone (Tibet, China)

Zhang

Zeng

2018

IJGI

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ASTER (Advanced Spaceborne Thermal Emission and Reflection) satellite imagery is useful in assisting lithologic mapping and, however, its effectiveness is yet to be evaluated for lithologic complex such as tectonic mélange. The Mugagangri Group (MG), the signature unit of the Bangong-Nujiang suture zone (BNSZ), Tibet and consisting of ophiolitic mélanges, was previously mapped as a single unit due to its poorly-described internal structures and an informative map with refined lithologic subdivision is needed for future petrologic and tectonic studies. In this paper, based on a combination of field work and ASTER data analysis, the MG is mapped as five subunits according to our newly-proposed lithologic subdivision scheme. In particular, we apply a data-processing sequence to first analyze the TIR band ratios to reveal approximate distribution of carbonates and silicate-dominated lithologies and then the VNIR/SWIR band ratios and false color images to differentiate the lithologic units and delineate their boundaries. The generalized procedures of ASTER data processing and lithologic mapping are applicable for future studies in not only the BNSZ but also other Tibetan ranges. Moreover, the mapping result is consistent with that the MG represents an accretionary complex accreted to the south Qiangtang margin as a result of northward-subduction of the Bangong-Nujiang oceanic crust.

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Mappable features of mélanges derived from Ocean Plate Stratigraphy in the Jurassic accretionary complexes of Mino and Chichibu terranes in Southwest Japan

Cited by 90 publications

References 28 publications

Composition, Provenance, and Tectonic Setting of the Southern Kangurtag Accretionary Complex in the Eastern Tianshan, NW China: Implications for the Late Paleozoic Evolution of the North Tianshan Ocean

Composition, Provenance, and Tectonic Setting of the Southern Kangurtag Accretionary Complex in the Eastern Tianshan, NW China: Implications for the Late Paleozoic Evolution of the North Tianshan Ocean

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

Mapping Lithologic Components of Ophiolitic Mélanges Based on ASTER Spectral Analysis: A Case Study from the Bangong-Nujiang Suture Zone (Tibet, China)

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