DOI: 10.1016/j.palaeo.2016.04.008
论文题名: Upper Lower Triassic stromatolite from Anhui, South China: Geobiologic features and paleoenvironmental implications
作者: Luo M. ; Chen Z.-Q. ; Shi G.R. ; Fang Y. ; Song H. ; Jia Z. ; Huang Y. ; Yang H.
刊名: Palaeogeography, Palaeoclimatology, Palaeoecology
ISSN: 0031-0182
出版年: 2016
卷: 452 起始页码: 40
结束页码: 54
语种: 英语
英文关键词: Bacteria clumps
; Coccoid-like spheroids
; Late Early Triassic
; Micro-quartz
; South China
; Stromatolite
英文摘要: Widespread stromatolites and other microbialite deposits characterize Lower Triassic marine successions worldwide. This study documents a stromatolite deposit, 1.1 m thick, from the upper Spathian (Lower Triassic) of the Susong area, South China. The stromatolite comprises distinct laminated domes in the basal part and columns at the upper part. Dark laminae are loosely spaced and interlayered with thicker light colored laminae. Diffusive dark colored laminae are composed of peloidal micrite that grade locally into microclotted structures, and yield copies of bacteria clump-like and coccoid-like spheroid aggregates. The former are characterized by cloudy, micrite nuclei rimmed by coarse-grained, euhedral sparry calcite crystals, while the latter are comprised of solid calcite crystal nuclei coated with rather thin micrite envelopes. The cloudy, micrite nuclei resemble bacteria clump-like structures observed in present-day travertine. Both the coccoid-like spheroids and bacteria clump-like structures are surrounded by coarse-grained euhedral calcite crystals, suggesting a similar accretion mechanism. Both spherical structures therefore could be crucial in the accretion of the Susong stromatolite. The laminated/microclotted structures are interpreted as the result of variation in timing of lithification relative to the timing of the decay of microbes. Micro-analysis also unravels the common occurrence of authigenic micro-quartz crystals in association with Fe-bearing illite clay minerals in the stromatolite columns. Their coalescing nature with each other, together with the associated pyrite grains, strongly support the formation of micro-quartz crystals from microbial reduction of an Fe-bearing smectite precursor by sulfate reducing bacteria. A comparison of the Susong stromatolite with its counterparts from the upper Lower Triassic strata in Dajiang, South China reveals many similarities in stromatolite microstructures, suggesting that a harsh, euxinic-anoxic environment resulting in the bloom of sulfate reducing bacteria most likely extended into the latest Spathian in South China. © 2016 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/68423
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China; Deakin University, School of Life and Environmental Sciences, Burwood Campus, 221 Burwood Highway, Burwood, VIC, Australia; School of Resources and Environmental Engineering, Hefei University of Technology, Hefei, China
Recommended Citation:
Luo M.,Chen Z.-Q.,Shi G.R.,et al. Upper Lower Triassic stromatolite from Anhui, South China: Geobiologic features and paleoenvironmental implications[J]. Palaeogeography, Palaeoclimatology, Palaeoecology,2016-01-01,452