An Early Triassic (Smithian) stromatolite associated with giant ooid banks from Lichuan (Hubei Province), South China: Environment and controls on its formation
An Early Triassic (Smithian) stromatolite associated with giant ooid banks from Lichuan (Hubei Province), South China: Environment and controls on its formation
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与中国南方利川（湖北省）巨型鲕滩有关的早三叠世（史密斯期）叠层石：环境及其形成的控制
DOI：
10.1016/j.palaeo.2017.02.006
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发表时间：
2017-11
期刊：
影响因子：
--
通讯作者：
Mao Luo
中科院分区：
文献类型：
--
作者：
Yuheng Fang;Zhong-Qiang Chen;Stephen Kershaw;Yang Li;Mao Luo
本文报道了鄂西利川地区下三叠统上史密斯统巨型鲕滩内发育的迄今记录最厚的早三叠统叠层石。大约16米厚的叠层石嵌在大冶组上部约30米厚的鲕状灰岩中。相关的牙形刺表明叠层石-卵状复合体的时代为晚史密斯时代（早三叠纪）。叠层石表现为穹状、分层柱状、波浪状、卷心菜状、卷状和锥形结构。叠层石上覆有较厚的鲕状灰岩，表明利川叠层石的消亡可能与浅水搅动的环境变化有关。叠层石具有四种微生物诱导的微结构，包括弥漫性层状微结构、网状微结构、碎屑内微结构和不规则凝块微结构。这些微生物诱导的微观结构的共存表明了利川叠层石的生物成因。球体可分为圆形、复合型、浅表型和不规则型。卵状体内部的一些内层表现出强烈的荧光，表明微生物有机矿化作用，这可能有助于形成卵状体。此外，丰富的纳米级结构和颗粒通常被解释为白云岩形成过程中微生物的参与。叠层石和流体中的这些纳米结构以及叠层石中常见的自生石英颗粒可归因于海水中丰富的有机物，这是微生物增殖的结果。这里描述的叠层石是早三叠世中期古特提斯洋东西边缘微生物群落繁荣的证据，表明二叠纪-三叠纪大灭绝后海洋生态系统的间歇性退化。
Here we report the thickest Early Triassic stromatolite so far recorded, which developed within giant ooid banks in the upper Smithian succession (Lower Triassic) of the Lichuan area, western Hubei Province, South China. Approximately 16 m of stromatolite is embedded within ca. 30-m-thick oolitic limestones that crop out in the upper Daye Formation. The associated conodonts suggest a late Smithian (Early Triassic) age for the stromatolite-ooid complex. Stromatolites exhibit domal, stratified columnar, wavy laminated, cabbage-shaped, roll-up, and conical structures. Stromatolites are overlain by thick oolitic limestone, implying that the demise of the Lichuan stromatolite may be attributed to an environmental change to agitated shallow waters. Four types of microbially-induced microstructures are recognizable in the stromatolites, including diffuse laminated, reticular, intraclastic, and irregular clotted microstructures. Co-occurrence of these microbe-induced microstructures indicates a biogenic origin for the Lichuan stromatolite. The ooids can be categorized into circular, compound, superficial, and irregular types. Some interior layers within ooids exhibit intense fluorescence, indicative of microbial organomineralization, which may have contributed to the formation of the ooids. Moreover, abundant nanometer-scale textures and particles are usually interpreted as microbial involvement during the formation of the dolomite. These nano-textures in both stromatolites and ooids, and authigenic quartz grains commonly preserved in stromatolite can be attributed to abundant organic matter in seawater, resulting from microbial proliferation. The stromatolites described here are evidence of flourishing microbial communities on both eastern and western margins of the Paleo-Tethys Ocean during the middle Early Triassic, suggesting episodic degradation of marine ecosystems after the Permian–Triassic mass extinction.
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影响因子：
12.1
作者：
A. Woods
通讯作者：
A. Woods
影响因子：
1.8
作者：
S. Kershaw;Li Guo;A. Swift;Jiasong Fan
通讯作者：
S. Kershaw;Li Guo;A. Swift;Jiasong Fan
影响因子：
2.8
作者：
Baumgartner, LK;Reid, RP;Visscher, PT
通讯作者：
Visscher, PT
影响因子：
2
作者：
G. Friedman;Vijai Shukla
通讯作者：
G. Friedman;Vijai Shukla
DOI：
10.1017/cbo9780511529498.011
发表时间：
1992
期刊：
--
影响因子：
--
作者：
Ding Meihua
通讯作者：
Ding Meihua