Resolving MISS conceptions and misconceptions: A geological approach to sedimentary surface textures generated by microbial and abiotic processes
Resolving MISS conceptions and misconceptions: A geological approach to sedimentary surface textures generated by microbial and abiotic processes
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DOI：
10.1016/j.earscirev.2016.01.005
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发表时间：
2016-03-01
影响因子：
12.1
通讯作者：
Miller, Randall F.
中科院分区：
文献类型：
--
作者：
Davies, Neil S.;Liu, Alexander G.;Miller, Randall F.
岩石记录包含硅质碎屑砂岩、粉砂岩和泥岩层理面上丰富多样的沉积表面纹理。近年来，越来越多的这些纹理被归因于沉积时的表面微生物垫，导致它们被分类为微生物诱发的沉积结构（MISS）。对 MISS 的研究发展迅速，导致文献中出现了许多误解。在这里，我们试图纠正这些MISS的误解。本文的第一部分调查了已报道的 MISS 的地层和环境范围，揭示了与普遍看法相反，已报道的显生宙含 MISS 岩石单元比前寒武纪更多。此外，MISS 展示了自太古代以来的泛环境和几乎连续的记录。关于 MISS 的地层限制在放牧生物进化之前或大规模灭绝事件之后的时间间隔的主张，以及 MISS 的环境限制的主张，似乎是抽样偏差的结果。在本文的第二部分中，我们建议提高对 MISS 的认识是以减少对可能产生形态相似特征的非生物过程的认识为代价的。通过引入“沉积表面纹理”这一总称术语（MISS 是其中的一个子集），我们提出了一种对地质记录中的此类结构进行分类的实用方法。我们说明了阐明古代沉积表面纹理的形成机制通常需要考虑来自周围地层的一系列沉积学证据。由此产生的解释，无论是微生物的还是非微生物的，都应在合理的不确定性范围内表达。这种方法认识到形态相似性本身并不能构成共同起源的科学证明，并恢复了沉积表面纹理的被动描述术语，而当前的 MISS 词典无法实现这一点。希望这个新术语能够减少 MISS 发生的过度耸人听闻和误导性的说法，并允许将初始观察与解释实际上分开。此外，这种方法提供了一种科学方法，认识到仅从视觉外观最终识别微生物结构的可能性很小，为在地球地质记录中以及可能在火星等其他行星体上寻找真正的 MISS 提供信息。 (C) 2016 年作者。由 Elsevier B.V. 出版
The rock record contains a rich variety of sedimentary surface textures on siliciclastic sandstone, siltstone and mudstone bedding planes. In recent years, an increasing number of these textures have been attributed to surficial microbial mats at the time of deposition, resulting in their classification as microbially induced sedimentary structures, or MISS. Research into MISS has developed at a rapid rate, resulting in a number of misconceptions in the literature. Here, we attempt to rectify these MISS misunderstandings. The first part of this paper surveys the stratigraphic and environmental range of reported MISS, revealing that contrary to popular belief there are more reported MISS-bearing rock units of Phanerozoic than Precambrian age. Furthermore, MISS exhibit a pan environmental and almost continuous record since the Archean. Claims for the stratigraphic restriction of MISS to intervals prior to the evolution of grazing organisms or after mass extinction events, as well as claims for the environmental restriction of MISS, appear to result from sampling bias. In the second part of the paper we suggest that raised awareness of MISS has come at the cost of a decreasing appreciation of abiotic processes that may create morphologically similar features. By introducing the umbrella term 'sedimentary surface textures', of which MISS are one subset, we suggest a practical methodology for classifying such structures in the geological record. We illustrate how elucidating the formative mechanisms of ancient sedimentary surface textures usually requires consideration of a suite of sedimentological evidence from surrounding strata. Resultant interpretations, microbial or non-microbial, should be couched within a reasonable degree of uncertainty. This approach recognizes that morphological similarity alone does not constitute scientific proof of a common origin, and reinstates a passive descriptive terminology for sedimentary surface textures that cannot be achieved with the current MISS lexicon. It is hoped that this new terminology will reduce the number of overly sensational and misleading claims of MISS occurrence, and permit the means to practically separate initial observation from interpretation. Furthermore, this methodology offers a scientific approach that appreciates the low likelihood of conclusively identifying microbial structures from visual appearance alone, informing the search for true MISS in Earth's geological record and potentially on other planetary bodies such as Mars. (C) 2016 The Authors. Published by Elsevier B.V.