Platform-wide shift to microbial carbonate production during the late Aptian
Platform-wide shift to microbial carbonate production during the late Aptian
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DOI：
10.1130/g46325.1
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发表时间：
2019-08
期刊：
影响因子：
5.8
通讯作者：
Katharina E. Schmitt;U. Heimhofer;G. Frijia;S. Huck
中科院分区：
文献类型：
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作者：
Katharina E. Schmitt;U. Heimhofer;G. Frijia;S. Huck
在主要的中生代生物危机之后，各种后生动物为主的珊瑚礁生态系统通常被微生物碳酸盐生产社区所取代。除了后生动物竞争对手的损失，在浅水平台设置造成普遍的微生物碳酸盐生产的因素还没有完全理解。其中，突出的温暖温度加上低氧沃茨被认为是可能的触发因素。本文研究了特提斯洋中部亚平宁碳酸盐台地（ACP）上阿普第晚期浅海碳酸盐岩。通过建立一个综合的高分辨率化学地层框架的两个部分的ACP，普遍bacineloid生长的同时代发病被发现，表明平台范围内的转变，从后生动物为主的生态系统微生物碳酸盐生产。微生物增殖的初始阶段与所谓的Aptian晚期"寒流"的最后阶段以及随后的温度升高相吻合，这是由于海平面显著上升而引起的。我们的研究结果与早期Aptian海洋缺氧事件1a的观察结果形成对比，在该事件中，微生物“bacineloid”碳酸盐生产的类似转变与异常温暖的条件和缺氧有关。
In the aftermath of major Phanerozoic biocrises, diverse metazoan-dominated reef ecosystems were commonly replaced by microbial carbonate-producing communities. Apart from the loss of metazoan competitors, the factors causing pervasive microbial carbonate production in shallow-water platform settings are not completely understood. Amongst others, outstanding warm temperatures coupled with low-oxygen waters were proposed as possible triggers. This study focuses on late Aptian shallow marine carbonates deposited on the Apennine carbonate platform (ACP) in the central Tethys. By establishing an integrated high-resolution chemostratigraphic framework for two sections of the ACP, the coeval onset of pervasive bacinelloid growth is discovered, indicating a platform-wide shift from a metazoan-dominated ecosystem to microbial carbonate production. The initial phase of microbial proliferation coincides with the final stage of the so-called late Aptian “cold snap” and the subsequent temperature increase, which was paralleled by a significant sea-level rise. Our results contrast with observations from the early Aptian Oceanic Anoxic Event 1a, where a similar shift toward microbial “bacinelloid” carbonate production has been linked to exceptionally warm conditions and hypoxia.