Environment and Age of the Upper Devonian–Carboniferous Zhulumute and Hongguleleng Formations, Junggar Basin, NW China: Ichnological and Palynological Aspects

Abstract

Two Upper Devonian to Lower Carboniferous sections, namely the Bulongguoer and Haer (Gennaren area) in the Junggar Basin, Central Asian Orogenic Belt, in northwestern China were examined with regard to ichnology and palynology. The deposits of the Hongguleleng Formation and Namu Member of the Heishantou Formation, respectively, are mostly unbioturbated or poorly bioturbated, with poorly diversified trace fossils, which indicate unfavourable conditions for the burrowing benthic community during the Late Devonian and Early Carboniferous. The main factor governing the growth of the bioturbating population was the rapid sedimentation of fine‐grained, volcanic material documented as tempestites, which buried the benthic fauna. In the Bulongguoer section, the presence of miospores Teichertospora torquata and Grandispora gracilis enabled identification of the broad Teichertospora torquata‐Grandispora gracilis Miospore Zone from the transitional Frasnian/Famennian interval. More accurate identification of palynostratigraphical levels (DE and CZ Miospore zones) is only tentative. On the basis of palynofacies analysis, samples from the lower Bulongguoer section indicate deposition in more proximal conditions, whereas samples from the top of the section indicate deposition in a more distal environment. In the Haer section, only a general biostratigraphic indication for the Tournaisian was possible, owing to poor preservation of organic matter.

Updating Frasnian miospore zonation from the Boulonnais (Northern France) and comparison with new data from the Upper Palaeozoic cover on the Brabant Massif (Western Belgium)

“…Consequently it is proposed here (Table 4) that a correlation exists between part of the V errucosisporites bulliferus-Lophozonotriletes media (BM) Oppel Zone, all of the The transition from the Rugospora bricei-Cymbosporites acanthaceus (BA) Oppel Zone and the Knoxisporites dedaleus-Diducites versabilis (DV) Oppel Zone of Western Europe crossing the Frasnian-Famennian Boundary is tentatively recognised in the lowermost part of the Honggelelung Formation in the Bulongguoer section of the Junggar Basin in NW China (Stachacz et al, 2020). The Frasnian/Famennian Boundary is dated by Zircon-U-Pb (371.5 ± 0.9 Ma) immediately below the Honggelelung Formation, in the Zhulumute Formation in the same region (Zheng et al, 2020).…”

Palynological analysis of the lower member of the Hongguleleng Formation and discussion of the Frasnian/Famennian boundary in Western Junggar, NW China

“…3; Streel et al, 1987;Avkhimovitch et al, 1993). More recently, the appearance of Teichertospora torquata and Grandispora gracilis in the Lower member of the Hongguleleng Formation, distinguished by Stachacz et al (2020), enabled the identification of the TG miospore Biozone from the F/F transition.…”

“…Lu (1999) systematically described the palynomorphs from the overlying Heishantou Formation, whereas the palynological assemblages of the underlying strata from the upper part of the Hujiersite Formation (Emsian-Frasnian) from this region were subsequently studied by Xu et al (2014). More recently, Stachacz et al (2020) analyzed palynologically and ichnologically the Hongguleleng (from the Bulongguoer and Haer sections) and the overlying Heishantou formations in more detail. The presence of the miospore species Grandispora gracilis and Teichertospora torquata enabled the identification of the wider Teichertosproa torquata -Grandispora gracilis miospore Biozone from the F/F transitional interval (Stachacz et al, 2020), but the precise position of the F/F boundary remains uncertain.…”

“…More recently, Stachacz et al (2020) analyzed palynologically and ichnologically the Hongguleleng (from the Bulongguoer and Haer sections) and the overlying Heishantou formations in more detail. The presence of the miospore species Grandispora gracilis and Teichertospora torquata enabled the identification of the wider Teichertosproa torquata -Grandispora gracilis miospore Biozone from the F/F transitional interval (Stachacz et al, 2020), but the precise position of the F/F boundary remains uncertain.…”

The Hushoot Shiveetiin gol section (Baruunhuurai Terrane, Mongolia): sedimentology and facies from a Late Devonian island arc setting

“…Furthermore, bryozoans and crinoids expanding from shallow-water refugia support the idea of the CAOB as a biodiversity hotspot (Waters et al 2003;Webster and Waters 2009;Ernst 2013;Waters et al this issue). Recent fieldwork in the Upper Devonian deposits from the CAOB within western Mongolia (Kido et al 2013;Ariunchimeg et al 2014;Suttner et al 2020) and analogous sites in NW-China (Suttner et al 2014;Carmichael et al 2014;Wang et al 2016;Stachacz et al 2020) suggest that the Hushoot Shiveetiin gol site in the Baruunhuurai Terrane in western Mongolia (which represents a shallow-water/neritic palaeoenvironment) is likewise essential for understanding biodiversity patterns in isolated ecosystems in the aftermath of the F/F events.…”