86989 20200716101444.0 doi 10.1111/sed.12577 sideral 111262 ART-2019-111262 eng (orcid)0000-0002-2141-2624 Martin-Bello, L. Universidad de Zaragoza Lacustrine stromatolites: Useful structures for environmental interpretation – an example from the Miocene Ebro Basin 2019 Access copy available to the general public Unrestricted The significance of stromatolites as depositional environmental indicators and the underlying causes of lamination in the lacustrine realm are poorly understood. Stromatolites in a ca 600 m thick Miocene succession in the Ebro Basin are good candidates to shed light on these issues because they are intimately related to other lacustrine carbonate and sulphate facies, grew under variable environmental conditions and show distinct lamination patterns. These stromatolites are associated with wave-related, clastic-carbonate laminated limestones. Both facies consist of calcite and variable amounts of dolomite. Thin planar stromatolites (up to 10 cm thick and less than 6 m long) occurred in very shallow water. These stromatolites represented first biological colonization after: (i) subaerial exposure in the palustrine environment (i.e. at the beginning of deepening cycles); or (ii) erosion due to surge action, then coating very irregular surfaces on laminated limestones (i.e. through shallowing or deepening cycles). Sometimes they are associated with evaporative pumping. Stratiform stromatolites (10 to 30 cm high and tens of metres long) and domed stromatolites (10 to 30 cm high and long) developed in deeper settings, between the surge periods that produced hummocky cross-stratification and horizontal lamination offshore. Changes in stromatolite lamina shape, and thus in the growth forms through time, can be attributed to changes in water depth, whereas variations in lamina continuity are linked to water energy and sediment supply. Growth of the stromatolites resulted from in situ calcite precipitation and capture of minor amounts of fine-grained carbonate particles. Based on texture, four types of simple laminae are distinguished. The simple micrite and microsparite laminae can be grouped into light and dark composite laminae, which represent, respectively, high and low Precipitation/Evaporation ratio periods. Different lamination patterns provide new ideas for the interpretation of microbial laminations as a function of variations in climate-dependent parameters (primarily the Precipitation/Evaporation ratio) over variable timescales. info:eu-repo/grantAgreement/ES/MINECO/BES-2014-069389 info:eu-repo/grantAgreement/ES/MINECO/CGL2013-42867-P info:eu-repo/semantics/openAccess All rights reserved http://www.europeana.eu/rights/rr-f/ 3.405 2019 GEOLOGY 5 / 47 = 0.106 2019 Q1 T1 1.491 2019 Stratigraphy 2019 Q1 Geology 2019 Q1 info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion (orcid)0000-0002-4212-0524 Arenas, C. Universidad de Zaragoza Jones, B. 2000 280 Universidad de Zaragoza Dpto. Ciencias de la Tierra Área Estratigrafía 66, 6 (2019), 2098-2133 Sedimentology SEDIMENTOLOGY 0037-0746 3512163 http://zaguan.unizar.es/record/86989/files/texto_completo.pdf Postprint 41025 http://zaguan.unizar.es/record/86989/files/texto_completo.jpg?subformat=icon icon Postprint oai:zaguan.unizar.es:86989 articulos driver 2020-07-16-09:01:14 ARTICLE