Small microbialites from the basal Triassic mudstone (Tieshikou, Jiangxi, South China): Geobiologic features, biogenicity, and paleoenvironmental implications

Yang, Hao; Chen, Zhong‐Qiang; Kershaw, Stephen; Liao, Wei; Lü, Enlü; Huang, Yuangen

doi:10.1016/j.palaeo.2018.06.030

Cited by 15 publications

(5 citation statements)

References 85 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Looking in other areas, similar digitate structures of the same age and containing fine columnar laminations are described from Tieshikou in South China (Yang et al, 2019). The authors use the terms of digitate microbialites, of laminated columns and of microstromatolite grew.…”

Section: Discussionmentioning

confidence: 92%

Sponge Takeover from End-Permian Mass Extinction to Early Induan Time: Records in Central Iran Microbial Buildups

et al. 2021

View full text Add to dashboard Cite

The end-Permian mass extinction was the most severe biotic crisis in Earth’s history. In its direct aftermath, microbial communities were abundant on shallow-marine shelves around the Tethys. They colonized the space left vacant after the dramatic decline of skeletal metazoans. The presence of sponges and sponge microbial bioherms has largely gone unnoticed due to the sponges’ size and the cryptic method of preservation. In addition to sponge dominated facies recently described in South Armenia and Northwestern Iran, we describe here sponge-microbial bioherms cropping out in two well-known Permian-Triassic boundary localities: the Kuh-e Hambast section, south-east of Abadeh city and the more distal Shahreza section, near Isfahan. In both sections, the extinction horizon is located at the top of an upper Changhsingian ammonoid-rich nodular limestone, called Paratirolites limestone. At Kuh-e Hambast, the overlying decimetric thick shale deposit called “boundary clay,” the latest Permian in age, is conformably overlain by well-dated transgressive basal Triassic platy limestone containing four successive levels of decimeter to meter scale, elongated to form cup-shaped mounds made of branching columnar stromatolites. Sponge fibers from possibly keratose demosponge, are widely present in the lime mudstone matrix. At the Shahreza section, above the extinction level, the boundary clay is much thicker (3 m), with thin platy limestone intervals, and contains two main levels of decimeter to meter scale mounds of digitate microbialite crossing the Permian-Triassic boundary with similar sponge fibers. Three levels rich in thrombolite domes can be seen in the overlying 20 m platy limestone of earliest Triassic age. Sponge fibers and rare spicules are present in their micritic matrix. These sponge fibers and spicules which are abundant in the latest Permian post-extinction boundary clay, followed microbial buildups during the Griesbachian time.

show abstract

Section: Discussionmentioning

confidence: 92%

Sponge Takeover from End-Permian Mass Extinction to Early Induan Time: Records in Central Iran Microbial Buildups

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Previous suggestions that deeper anoxic waters upwelled or overturned and spilled into areas of microbialite growth (Baresel et al., 2017; Liao et al., 2017; G. M. Luo et al., 2013) are shown to be invalid by our results because ramp and intraplatform basin settings were mostly oxic at that time (Figure 4c). This inference is also strengthened by the presence of abundant framboids, indicative of a dysoxic state, in stromatolite nodules embedded within mudstone of intraplatform basin facies, and their absence in the surrounding mudstone in TSK section (Yang et al., 2019). The microbial growth clearly created localized anoxic conditions favorable for the growth of framboids after the LPME.…”

Section: Discussionmentioning

confidence: 99%

“…At YDZ, the uppermost Permian bioclastic limestone is overlain unconformably by a basal Triassic microbialite unit. The TSK section consists of shallow platform bioclastic limestone in the upper Permian portion, transitioning to ramp facies (thin‐bedded muddy limestone) in the uppermost Permian, and basinal mudstone in the lowest Triassic (Figure 2) which yields small bowl‐like microbialites (Yang et al., 2019). The other two sections (CH and SS) are basinal and comprise uppermost Permian siliceous shale and cherty limestone overlain by the basal Triassic marlstone and mudstone of the basal Daye/or Feixianguan Formation.…”

Section: Introductionmentioning

confidence: 99%

Microbial Blooms Triggered Pyrite Framboid Enrichment and Oxygen Depletion in Carbonate Platforms Immediately After the Latest Permian Extinction

Chen

Fang

Wignall

et al. 2022

Geophysical Research Letters

View full text Add to dashboard Cite

Redox variations across the Permian‐Triassic boundary (PTB) have long been debated, especially during the proliferation of PTB microbialites. Here, we report redox fluctuations across the PTB to evaluate links between the two based on pyrite framboid analysis from basin to platform settings in South China. During the end‐Permian extinction, abundant framboids indicate a widespread anoxia that was likely a direct cause of extinction. In the earliest Triassic (Hindeodus parvus conodont zone), pyrite framboids were absent in ramp to basin and shallow, nonmicrobialite platform sections. In contrast, the coeval microbialites yield abundant framboids indicative of dysoxia. The fact that framboids were only confined to PTB microbialites and absent in other habitats indicates that microbe bloom may have stimulated dysoxic watermass and triggered the framboid growth within microbe aggregates. Thus, microbialites were not built in reducing settings, but instead, microbial proliferation caused local, dysoxia within shallow oxygenated platforms after the extinction.

show abstract

“…The Upper Permian shale unit, assigned to the Dalong Formation (P 3 d), is composed of black to dark‐grey carbonaceous shale and siliceous shale, and this unit is interpreted to represent an intraplatform basin (Chen, Jin, & Shi, ; Chen, Tong, Liao, & Chen, ；; Chen et al, ; Figure b). In addition, black shales and mudstones are also very pronounced in the Lower Triassic successions in the Lower Yangtze area, and they are usually assigned to the Yinkeng Formation, Helongshan Formation, or the Lower Qinglong Formation (Chen et al, , ; Chen, Tong, & Fraiser, ; Yang et al, ). However, the total organic contents (TOC) are relatively poor (Zou et al, ), although some microbialites or microbial nodules are developed in these strata (Chen et al, ; Wu et al, ; Yang et al, ).…”

Section: Geological Settingmentioning

confidence: 99%

“…In addition, black shales and mudstones are also very pronounced in the Lower Triassic successions in the Lower Yangtze area, and they are usually assigned to the Yinkeng Formation, Helongshan Formation, or the Lower Qinglong Formation (Chen et al, , ; Chen, Tong, & Fraiser, ; Yang et al, ). However, the total organic contents (TOC) are relatively poor (Zou et al, ), although some microbialites or microbial nodules are developed in these strata (Chen et al, ; Wu et al, ; Yang et al, ). The Lower Triassic shale units therefore are not considered as the potential shale gas reservoirs in this study.…”

Section: Geological Settingmentioning

confidence: 99%

The Lower Yangtze area: A next shale gas block for China? Preliminary potential assessment from some geology and organic geochemistry information

Chen

et al. 2019

Geological Journal

View full text Add to dashboard Cite

In the last several years, the massive success of the Fuling shale gas field in south‐western China has shown great potential in finding giant shale gas fields in the Upper Yangtze area, and it has also attracted the increasing attention from geologists to find more shale gas reservoirs around the world. However, there is still a great dispute as to whether the neighbouring Lower Yangtze area is a next potential shale gas block in China. In this study, we evaluate preliminarily the shale gas potentials of five important sets of marine shales based on systematic analyses for the sedimentary environment, thickness, total organic carbon (TOC), thermal maturity, and other organic geochemistry parameters of both geological records from outcrops and wells in the Lower Yangtze area. The first two sets of marine shales occur in the Lower Cambrian and the Ordovician, and they all are of over–high organic maturity due to strong effects from regional tectonic movements and thus have poor potential. Although the Lower Silurian shales are widely distributed in the Lower Yangtze region, a terrigenous delta, a low amount of organic matter (TOC < 1.2%), and late tectonic activity together created unfavourable conditions for the generation and accumulation of the Lower Silurian shale gas. The Permian black shales occur in the Middle and Upper Permian. Several proxies, such as the appropriate maturity (vitrinite reflectance Ro of approximately 2.0%), abundant organic matter (TOC of approximately 4 wt%), good total hydrocarbon potential (S1 + S2), and high level of hydrocarbon conversion have resulted in good conditions for shale gas generation. However, the relative thinness (only 30 m), severe tectonic modification, and regional cap rock are not favourable for shale gas preservation. The Lower Yangtze area therefore is not an excellent block for shale gas exploration compared to its neighbouring Upper Yangtze area. However, in some areas with less structural deformation, the possibility of finding shale gas reservoirs cannot be ruled out, especially for the Permian shales, which had a greater opportunity to generate and accumulate shale gas than the other marine shales. In addition, for new shale gas exploration breakthroughs in the future, structural studies are essential in offering better understanding of the preservation conditions in the Lower Yangtze area.

show abstract

Small microbialites from the basal Triassic mudstone (Tieshikou, Jiangxi, South China): Geobiologic features, biogenicity, and paleoenvironmental implications

Cited by 15 publications

References 85 publications

Sponge Takeover from End-Permian Mass Extinction to Early Induan Time: Records in Central Iran Microbial Buildups

Sponge Takeover from End-Permian Mass Extinction to Early Induan Time: Records in Central Iran Microbial Buildups

Microbial Blooms Triggered Pyrite Framboid Enrichment and Oxygen Depletion in Carbonate Platforms Immediately After the Latest Permian Extinction

The Lower Yangtze area: A next shale gas block for China? Preliminary potential assessment from some geology and organic geochemistry information

Contact Info

Product

Resources

About