Water-level and redox fluctuations in a Sichuan Basin lacustrine system coincident with the Toarcian OAE
Water-level and redox fluctuations in a Sichuan Basin lacustrine system coincident with the Toarcian OAE
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与吐阿尔阶 OAE 一致的四川盆地湖泊系统的水位和氧化还原波动
DOI：
10.1016/j.palaeo.2020.109942
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发表时间：
2020-11
期刊：
影响因子：
--
通讯作者：
Liao Zhiwei
中科院分区：
文献类型：
--
作者：
Liu Jinchao;Cao Jian;Hu Guang;Wang Yan;Yang Ruofei;Liao Zhiwei
越来越多的海洋缺氧事件（OAEs）在陆地沉积物中有记录，这为OAEs的研究提供了高分辨率的资料。然而，目前的工作是初步的，需要更多的地质分析来测试。本文以吐哈盆地下侏罗统大安寨段为例，对吐哈盆地下侏罗统大安寨段地层进行了研究。180 Ma）四川盆地。根据大安寨段的岩石学和沉积相特征，重建了四川盆地相对水位的变化，揭示了与全球同期海平面变化相一致的相对水位变化。大安寨段沉积于全球海侵后海平面普遍较高的时期，Sr/Ba和S/TOC比值证实了湖盆变浅和盐度升高的趋势。在湖泊变浅过程中，在较短的时间尺度上存在4个完整的次级湖泊变深-变浅旋回。总有机碳含量和有机碳同位素地层学研究表明，大安寨段记录的T-OAE具有广泛的陆源响应。Mo相对于PAAS的富集因子（MoEF）和Corg/P值表明，钼的氧化还原条件不稳定。OAE的陆地响应可能是由水文条件的变化引起的，这与卡鲁-费拉尔大火成岩省引发的全球变暖有关。相关的有机碳积累机制是提高初级生产力和缺氧保存条件的综合作用。我们的数据表明，OAE确实有陆地响应，并诱导有机碳积累，但机制仍然不是很清楚，需要进一步研究。
Increasing cases have indicated that oceanic anoxic events (OAEs) appear to have records in terrestrial sediments, which provide valuably high-resolution materials for the debated and challenging issues of OAEs. However, the current works are preliminary and need more geological analyses to test. Here we present a case study in the Lower Jurassic Da'anzhai Member of the Toarcian (ca. 180 Ma) Sichuan Basin, SW China. The petrology and sedimentary facies of the Da'anzhai Member were used to reconstruct the relative water-level fluctuations in the Sichuan Basin, which are revealed to be consistent with coeval changes in global sea levels. The Da'anzhai Member was deposited during a period of lake shallowing with enhanced salinities corroborated by the Sr/Ba and S/TOC ratios, when sea level was generally high after global transgression. During the lake shallowing, there were four complete secondary lacustrine deepening–shallowing cycles over shorter time-scales. The total organic carbon contents and organic carbon isotopic stratigraphy show there was a basin wide terrestrial response to the T-OAE as recorded by the Da'anzhai Member. The enrichment factors of Mo relative to PAAS (MoEF) and Corg/P values imply a dysoxic redox condition. The terrestrial response of OAEs is likely caused by changes in hydrological conditions, which were related to the global warming triggered by the Karoo–Ferrar Large Igneous Province. The associated organic carbon accumulation mechanism is a combined effect of elevated primary productivity and oxygen-depleted preservation conditions. Our data suggest that OAEs do have terrestrial response and induce organic carbon accumulation, but the mechanisms are still not much clear and need further studies.
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影响因子：
5.3
作者：
Hesselbo, Stephen P.;Pienkowski, Grzegorz
通讯作者：
Pienkowski, Grzegorz
DOI：
10.1080/10020070412331343331
发表时间：
2004-02
期刊：
Progress in Natural Science
影响因子：
--
作者：
S. Cao;D. Ma;Jiayong Pan
通讯作者：
S. Cao;D. Ma;Jiayong Pan
DOI：
10.1016/j.palaeo.2020.109674
发表时间：
2020-05
期刊：
Palaeogeography, Palaeoclimatology, Palaeoecology
影响因子：
--
作者：
Li Wang;Yankuan Tian;Jiaju Zhao
通讯作者：
Li Wang;Yankuan Tian;Jiaju Zhao
影响因子：
4.6
作者：
Them TR;Gill BC;Selby D;Gröcke DR;Friedman RM;Owens JD
通讯作者：
Owens JD
影响因子：
16.6
作者：
Korte C;Hesselbo SP;Ullmann CV;Dietl G;Ruhl M;Schweigert G;Thibault N
通讯作者：
Thibault N