干旱区生态环境知识资源中心(Arid): Challenges to carbonate-evaporite peritidal facies models and cycles: Insights from Lower Cretaceous stromatolite-bearing deposits (Oncala Group, N Spain)

Arid

DOI	10.1016/j.sedgeo.2020.105752
	Challenges to carbonate-evaporite peritidal facies models and cycles: Insights from Lower Cretaceous stromatolite-bearing deposits (Oncala Group, N Spain)
	Quijada, I. Emma; Benito, M. Isabel; Suarez-Gonzalez, Pablo; Rodriguez-Martinez, Marta; Campos-Soto, Sonia
通讯作者	Quijada, IE
来源期刊	SEDIMENTARY GEOLOGY
ISSN	0037-0738
EISSN	1879-0968
出版年	2020
卷号	408
英文摘要	Peritidal carbonate-evaporite successions, since they are developed in the transition between continental and marine realms, provide essential keys for palaeobathymetric and palaeoclimatic interpretations. As a result, several facies models have been proposed to assist on the interpretation of ancient tidal flat deposits, and peritidal successions have been extensively used for cyclicity analyses. In this study, well-exposed, Lower Cretaceous peritidal deposits (Oncala Group, Cameros Basin, N Spain) are analysed and compared with the most commonly-used present-day analogues (from Shark Bay, the Arabian Gulf and the Bahamas) and with ancient peritidal successions, providing their palaeoenvironmental and palaeoclimatic interpretation, assessing the usefulness and limitations of the fades models, and evaluating the suitability of these deposits for analysis of decimetre to metre-scale cycles. The studied peritidal deposits consist of thinly-bedded to laminated dolostones, dolomitic stromatolites, stromatolite breccias, flat-pebble and edgewise breccias, and calcite and quartz pseudomorphs after anhydrite nodules. Abundant resemblances of the peritidal deposits of the Oncala Group with those of Shark Bay, including that they are largely composed of microbialites and intraclasts, makes the peritidal deposits of the Oncala Group one of the best fossil analogues of this present-day setting. However, the presence of anhydrite nodules indicates pervasive evaporite precipitation in the supratidal zone, which is a feature that does not occur in supratidal flats of Shark Bay, but is characteristic of arid sabkhas of the Arabian Gulf. Nevertheless, the fact that carbonate-evaporite tidal flats of the Oncala Group were laterally related with silidclastic tidal flats with large freshwater input and broadly inhabited by dinosaurs, suggests that anhydrides precipitated under less arid climates than those of the Arabian Gulf nowadays, pointing to semiarid climatic conditions during deposition. Moreover, the fact that peritidal deposits with anhydrite nodules were exclusively formed in a low-subsidence area of the Cameros Basin suggests that the rate of accommodation space creation also played an important role in their development. Regarding the comparison with other fossil peritidal sediments, the studied deposits show more abundant similarities with Proterozoic and Cambrian successions, composed mainly of stromatolites, microbial laminites, and intraclasts, than with other Mesozoic peritidal deposits, in which bioclasts and burrowing are usually more abundant. This highlights the difficulties for assigning specific features to certain geological ages. Finally, peritidal facies of the Oncala Group may change laterally and vertically to any other fades, showing a patchy lateral distribution of fades and an unsystematic vertical stacking pattern. The sedimentary features of the stromatolite, breccia and thinly-bedded to laminated dolostone facies do not allow their assignment to a unique tidal zone. Moreover, sedimentary features indicative of subaerial exposure, such as anhydrite nodules formed in the capillary zone, occur within any of the carbonate fades and show limited lateral extent. This results in a succession that cannot be clearly subdivided into subsequent shallowing-upward cycles not even by using erosive surfaces or the anhydrite nodule layers as marker horizons of the upper part of the cycles, because their limited lateral extent prevents reliable correlations. Similar composite lateral and vertical fades relationships have been documented both in the present-day analogues and in ancient successions, which suggests that this kind of fades relationships may be common in peritidal successions and highlights the caution that must be taken when trying to perform cyclicity analysis on them. (C) 2020 Elsevier B.V. All rights reserved.
英文关键词	Tidal flat Coastal sabkha Microbialites Anhydrite nodules Facies mosaic Cameros Basin
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000588308500007
WOS关键词	BASQUE-CANTABRIAN BASIN ; SEA-LEVEL CHANGES ; GREAT-SALT-LAKE ; CAMEROS BASIN ; ABU-DHABI ; SHARK BAY ; MICROBIAL DEPOSITS ; COASTAL SABKHA ; TIDAL-FLAT ; SEQUENCE STRATIGRAPHY
WOS类目	Geology
WOS研究方向	Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/327457
作者单位	[Quijada, I. Emma] Univ Oviedo, Dept Geol, C Jesus Arias de Velasco S-N, Oviedo 33005, Spain; [Benito, M. Isabel; Suarez-Gonzalez, Pablo; Rodriguez-Martinez, Marta; Campos-Soto, Sonia] Univ Complutense Madrid, Dept Geodinam Estratig & Paleontol, C Jose Antonio Novais 12, Madrid 28040, Spain; [Benito, M. Isabel] Inst Geociencias IGEO UCM CSIC, C Severo Ochoa 7, Madrid 28040, Spain
推荐引用方式 GB/T 7714	Quijada, I. Emma,Benito, M. Isabel,Suarez-Gonzalez, Pablo,et al. Challenges to carbonate-evaporite peritidal facies models and cycles: Insights from Lower Cretaceous stromatolite-bearing deposits (Oncala Group, N Spain)[J],2020,408.
APA	Quijada, I. Emma,Benito, M. Isabel,Suarez-Gonzalez, Pablo,Rodriguez-Martinez, Marta,&Campos-Soto, Sonia.(2020).Challenges to carbonate-evaporite peritidal facies models and cycles: Insights from Lower Cretaceous stromatolite-bearing deposits (Oncala Group, N Spain).SEDIMENTARY GEOLOGY,408.
MLA	Quijada, I. Emma,et al."Challenges to carbonate-evaporite peritidal facies models and cycles: Insights from Lower Cretaceous stromatolite-bearing deposits (Oncala Group, N Spain)".SEDIMENTARY GEOLOGY 408(2020).