The western edge of the Mediterranean Pelagian Platform: A Messinian mixed siliciclastic–carbonate ramp in northern Tunisia

The marine Messinian deposits of Tunisia cover a narrow littoral strip some 300 km long between the northern Bizerte and Cap Bon areas and the central–eastern Sahel region. Litho- and biofacies analysis of six stratigraphic sections reveals the distinctive features of these deposits.The lower Messinian deposits are characterized by ubiquitous siliciclastics and abundant oolitic/bioclastic limestones organized in an eastward facing ramp. Westward (landward), this ramp changes into coastal lagoons, sometimes containing evaporites. Eastward, the ramp passes to the reefal Pelagian Platform extending as far as Lampedusa.Two main sedimentary cycles are distinguished: 1) an early Messinian siliciclastic retrogradational then oolitic/bioclastic progradational cycle (Beni Khiar Formation and lower Oued bel Khedim Formation); 2) a late Messinian brackish to continental cycle that probably accumulated in rapidly subsiding lagoons (Oued el Bir Formation and upper Oued bel Khedim Formation). The Tunisian early Messinian cycle is partly eustatically controlled, but the late Messinian cycle cannot be confidently correlated to other well-known Messinian series because of tectonic movements.The lower Messinian deposits of Tunisia are also characterized by abundant suspension-feeding organisms (molluscs and bryozoans) and rare corals, calcareous algae, echinoids, and larger benthic foraminifers. The proposed palaeoenvironmental model shows that the lower Messinian ramp of Tunisia was located on a current-protected margin and subjected to continent-derived sediment and nutrient supply. Eastward, nutrient influx diminished and a shallow-water isolated carbonate platform with coralgal facies developed between the western and the eastern Mediterranean basins. The main hydrological connection between these two basins occurred through a narrow seaway situated to the northeast of the Pelagian Platform, south of Sicily and Malta.     

The Girvanella-like remains from Messinian marine deposits (Sardinia,Italy): Lagerstätten paradigm for microbial biota?

The lower Messinian marine sediments of the Capo San Marco Formation in the Sinis area (Sardinia, Italy) contain extensive carbonate buildups mainly made of microbialites. These microbialites exhibit general thrombolitic fabric and occur in meso-macroscopic scale as dominant cauliflower-like structures, digitations and encrusting rings. All the microbialites are here associated with serpulid tubes and bryozoan colonies. Examination of thin sections from microbialite samples reveal the presence of dense flexuous, not ramified and erect tubular micritic structures, with an external diameter ranging from 30 to 40 μm, all characters being very close to those of the Girvanella-type filaments. Although all microbialites show quite similar structural aspects, only two levels contain clearly visible networks of such filaments. The associated marine biota is diverse (cemented, borers, burrowers) related to the available biotopes (hard substrates, fine grained sediment, cavities…). The general scarcity of microbial remains in Messinian microbialites points out to the problem of taphonomic processes allowing a good preservation of microbial structures. The concept of Lagerstätten could well be extended to the preservation of microscopic organisms in the carbonate material. The discovery of Girvanella-like filaments demonstrates the implication of cyanobacterial organisms in the construction processes of the Messinian thrombolitic buildups. Furthermore, it is the first time that Girvanella-like microbialites are documented from Upper Miocene marine rocks.     

Upper miocene carbonate ramp deposits from the southernmost part of Maiella Nountain (Abruzzo, Central Italy)

Summary The development of carbonate ramp depositional systems in the Neogene of the Mediterranean Region represents a widespread feature so far analysed in several papers. It is striking to note that the evolution of upper Miocene carbonate ramps, characterized by the presence of coralgal bioherms, highlights the events leading to the Messinian salinity crisis. The coralgal bioherms of preevaporite Messinian age exhibit fossil assemblages indicating marine waters with normal salinity, whereas stromatolitic and microbial encrustations underline the deterioration of the environment during the Messinian salinity crisis. Maiella Mountain is a broad carbonate massif located in Abruzzo (Central Italy). The late lower Oligocene-Messinian part of its stratigraphic succession consists of stacked non-tropical carbonate ramp deposits related to third and higher order sequences. The investigations performed in the southernmost portion of the massif allowed to recognize a complete fourth order carbonate depositional sequence on a homoclinal ramp of pre-evaporite Messinian age. The presence of small coralgal patch reefs and overlaying microbial encrustations is significant. A transect exhibits the stratigraphic framework of the area. The data show how local parameters play a notable role in the development of these deposits.     

Signification paléoécologique des assemblages de diatomées du Messinien dans le bassin de Melilla-Nador (Rif Nord-Oriental, Maroc)

In the Melilla-Nador basin, the diatomites represent one of the main sedimentary components of the Messinian together with reefal carbonate platforms. Two vertical sections were realised in the diatomitic levels from distal platform. Diatom assemblages are for the first time described in this basin. A total of 125 diatom species were determined: 73 centrics and 52 pennates. Significant diatom assemblages defined from the statistical analysis indicate ecological variations concerning diatomitic levels or parts of diatomitic levels. Using the data sets we propose paleoenvironmental models showing the complexity of the ecological interactions. This study point the permanence of opened marine environment, the impulse of cold waters from Atlantic origin, a general decrease in bathymetry in the Messinian marls-diatomitic series, the influence of the carbonate platform progradation and the occurrence of upwelling systems.     

History of West Mediterranean newts,Pleurodeles (Amphibia: Salamandridae), inferred from old and recent DNA sequences

MtDNA sequences (396 bp cytochrome b and 369 bp 12S rRNA) from recent material and old museum specimens indicate Pleurodeles poireti and P. waltl form independent clades with 7.76% genetic divergence. Within P. poireti, populations from Djebel Edough, NE Algeria are very distinct with 6.12% genetic divergence from the remainder and may deserve separate species status. Away from Djebel Edough, P. poireti consists of three distinct clades (coastal NW Tunisia; central N Algeria; Constantine plus inland NW Tunisia) with a maximum genetic divergence of only 1%. P. waltl contains two clades with 2.96% genetic divergence, one in SE and E Spain plus north Morocco, the other in Portugal and SW and central Spain. Pleurodeles probably invaded NW Africa from SW Europe during the Messinian Salinity Crisis, when land contact was first established at 5.6 Ma, and then interrupted at 5.3 Ma. Molecular clocks, calibrated in the assumption that the latter event separated P. waltl and P. poireti, suggest that Pleurodeles diverged from its sister taxon, Tylototriton, at about 8.6–10 Ma. Djebel Edough P. poireti separated at about 4.2 Ma, perhaps through isolation on a temporary, now ‘fossil’, island initiated by the Messinian crisis. Differentiation in remaining P. poireti may have been caused by Pleistocene climatic fluctuations, while bifurcation in P. waltl appears to have taken place in the Pliocene approximately between 3.2 and 2 Ma. This species reached Morocco very recently, perhaps as a result of human introduction. Use in Pleurodeles of the slower divergence rates estimated in some other salamandrids results in a less parsimonious historical hypothesis that does not fit known geophysical events.     

Origin and evolution of an Upper Jurassic complex of carbonate buildups from Zegarowe Rocks (Kraków–Wieluń Upland, Poland)

The Upper Jurassic complex of Zegarowe Rocks is situated on the Kraków–Wieluń Upland in southern Poland. The complex is dominated by massive limestones representing carbonate buildups. The successive stages of carbonate buildup development include: colonisation, aggradational growth and progradation phases. In the colonisation phase, on top of loose peloidal-ooid sands micritic peloidal thrombolites developed. Peloidal and agglutinated thrombolites and stromatolites proliferated during the aggradational growth phase, whereas the progradation phase was characterised by shallowing and related development of agglutinated stromatolites with coprolites. The latter were the effect of periodical stabilisation of detrital sediments by microbial mats. The Zegarowe Rocks complex developed upon an elevation of the Late Jurassic stable northern shelf of the Tethys. This elevation was formed due to local decrease in subsidence rate, induced by the presence of a Palaeozoic granitoid intrusion in the shelf substratum. The carbonate buildups of the Zegarowe Rocks complex, initially developing as sediment-starved mounds upon fault-controlled intraplatform highs under strongly restricted background sedimentation rate, were replaced by agglutinated microbial reefs.     

Biomarker indications for microbial contribution to Recent and Late Jurassic carbonate deposits

Summary Biomarker investigations were applied to the hydrocarbon fractions of three Recent (cyanobacterial mat, Lake Van microbialite and Lake Satonda microbialite) and two Late Jurassic carbonate samples obtained from sponge bioherms. The relative concentrations ofn-alkanes, monomethyl alkanes, acyclic isoprenoids, steroids and hopanoids in these samples are studied and their probable biological precursors are discussed. Normal alkanes with carbon chain lengths ranging from C₁₅ to C₃₄ and monomethyl alkanes ranging from C₁₇ to C₂₁ with a varying methyl branching pattern are found. The major hydrocarbons are low molecular weight (LMW)n-alkanes (C₁₅–C₂₁) with a slight to strong predominance ofn-heptadecane (C₁₇). High molecular weight (HMW)n-alkanes occur in low to moderate relative concentrations showing a preference of odd-carbon numbered compounds with a maximum at C₂₉. Within the acyclic isoprenoids, pristane, phytane/phytene, pentamethyl-eicosane, squalane and lycopane could be identified. Polycyclic terpenoids of the sterane and/or hopane type are present in all carbonate samples. The carbon numbers of these components range from 27 to 29 and 27 to 32, respectively. These organic compounds identified can be attributed to various source organisms such as cyanobacteria, archaebacteria, algae and vascular plants. All hydrocarbon fractions of the samples are characterized by moderate to high relative concentrations of compounds derived from cyanobacteria, signifying the role of these organisms as contributors to the Recent as well as to the Late Jurassic carbonate deposits.     

?Microbialites in the Permian-Triassic boundary interval in central China: Structure, age and distribution

Summary A carbonate crust, with a principally digitate structure, caps latest Permian reef complexes in east Sichuan, China. The crust contains the conodontHindeodus parvus, confirming its age as earliest Triassic; it therefore closely postdates the end-Permian mass extinction, and is related to associated palaeoenvironmental change. Although its branches have lobate margins, and internal structures of radial fabrics and lobate fabrics in different specimens, an organic origin cannot be confirmed, because crust fabric is largely recrystallised. Therefore we apply the term ?microbialite to reflect uncertainty of its nature. The crust is co-eval (within theparvus Zone) with confirmed microbial biostromes and mounds in Guizhou Province, south of Sichuan. The sum of evidence, assembled by workers in several sites worldwide, indicates a sea-level rise occurred in the boundary interval, and this is corroborated by facies of the Sichuan crust. Abrupt appearance and disappearance of the crust, formed by precipitated carbonates, in east Sichuan, represents short-lived unusual post-extinction marine conditions which were switched abruptly on, then off. Microbial deposits overlying the P/T boundary in other locations in the Tethys Ocean (Iran and Japan) support the view that the unusual oceanic conditions had at least a regional distribution. Because the crust abruptly terminates, and is not succeeded by fossil-rich deposits, application of the disaster biota concept is inappropriate; an environmentally-driven control on carbonate precipitation is better supported by the evidence, whether or not it was biotically-mediated.     

Évolution des environnements littoraux du bassin de Melilla-Nador (Nord-Est Maroc) au Messinien supérieur entre 6,0 et 5,77 Ma

This study of late Messinian deposits (E2 = TCC) from Melilla-Nador carbonate complex (Morocco) allowed us to characterize the environmental evolution between 6.0 and 5.77 Ma, which is a period considered as contemporaneous of the onset and development of the “messinian salinity crisis”. A statistical approach coupled together with classical petrographic study allows us to constrain the sedimentary dynamic of platforms and to propose deposition environment models. The Melilla-Nador platforms E2 deposits show a progressive continuous evolution of littoral environments in two major stages of available space creation and infill. The first stage corresponds to the build up of a reef complex between 6.0 and 5.85 Ma then the second stage, between 5.85 and 5.77 Ma, corresponds to the development of a mixed oolitic shallow ramp during the progressive infill of Melilla-Nador basin. The comparison with the Sorbas basin (Spain) TCC deposits exhibits a very close evolution of late Messinian littoral environments, which could be used as a correlation tool.     

Paratethyan Ostracod immigrants in Italy during the Late Miocene

In this paper the ostracod assemblages recovered from several brackish Late Miocene Italian deposits have been analysed from a palaeobiogeographical perspective. During late Tortonian-early Messinian it is possible to recognize in Italy rich ostracod assemblages characterized by a wide contingent of taxa with central European or Mediterranean affinity, while only few brackish and freshwater ostracods show Paratethyan affinity. The recognized composition of the ostracod assemblages matches the palaeogeographic setting of the palaeo-Mediterranean/Paratethys at that moment. In fact during late Tortonian-early Messinian the palaeo-Mediterranean and Paratethysian domains were divided and, even if the connection via the present Marmara Sea-Strimon Basin was still open, the different salinity between them represented an ecological barrier, preventing faunal exchanges. Since normal aquatic migration was impossible, it must be assumed that the Paratethyan-like taxa entered the palaeo-Mediterranean area via passive dispersal by aquatic birds. On the contrary, the ostracod assemblages from the Italian Lago-Mare deposits show the absolute predominance of Paratethyan taxa, which, according to the known palaeogeographic setting during the late Messinian Lago-Mare event, could actively migrate from the Paratethys domain, colonizing the palaeo-Mediterranean, whose endemic fauna was severely impoverished by the Messinian salinity crisis and the following water dilution.     

Preferential dolomitization in Mio–Pliocene bioclastic clinoforms,Bonaire Island,South Caribbean: insights from petrographic and geochemical analyses

Facies - The late Aptian Lower Serdj Formation (LSF) in the Northern Atlas of Tunisia records a mixed carbonate–siliciclastic system from the southern margin of Tethys. Sedimentological...     

“Earliest Zanclean age for the Colombacci and uppermost Di Tetto formations of the « latest Messinian » northern Apennines: New palaeoenvironmental data from the Maccarone section (Marche Province, Italy)” by Popescu et al. (2007) Geobios 40 (359-373)

Two possible alternative interpretations of the claimed Zanclean age (Popescu et al., 2007) of two historical lithostratigraphic units of the Northern Apennines, usually referred to as Late Messinian in age and recording the so called Lagomare final event of the Messinian salinity crisis (MSC), are here discussed. The wrong age attribution of the Colombacci and “tetto” Fms. is ruled out based on data from the Maccarone and other sections showing that the Colombacci-Argille Azzurre Fm. boundary is basin wide synchronous and coincident with the Miocene-Pliocene boundary as far as it has been formally defined in the Eraclea Minoa GSSP. Alternatively, the opportunity of emending the Zanclean GSSP to a stratigraphically lower horizon recording the first evidence of marine influences in the Mediterranean following the MSC peak, seems not suitable, as (1) the marine signature of uppermost Messinian deposits is weak and still controversial and (2) no significant bio- and magnetostratigraphic events, well chronologically defined and recognizable at a global scale appear to be available to such a purpose.     

Histoire plio-pléistocène des écosystèmes végétaux de Méditerranée sud-occidentale : apport de l’analyse pollinique de deux sondages en mer d’Alboran

The pollen analysis of sediments of two boreholes located in the northeastern Morocco (Nador 1) and in the southeastern Spain (Andalucia G1) has allowed shedding a new light on the vegetation and climate of the North African littoral plains, the Rif Massif and the Betic Range during the Pliocene. The vegetation around the Alboran Sea was open and xeric during the Zanclean, dominated by herbs including subdesertic elements as Calligonum, Lygeum, Nitraria and Neurada. This type of vegetation indicates a dry and hot climate. The southwestern Mediterranean steppes have therefore a climatic character; they existed before the presence and the heavy pressure of Man on the environment. From the Piacenzian, the development, at Andalucia as well as at Nador, of Artemisia and the appearance of some altitude trees such as Cedrus and Cathaya indicate a vegetation change linked to a climatic change. Modifications in the vegetation observed during the same period in northwestern Mediterranean seem to indicate that the vegetation changes observed at Andalucia and Nador are controlled by the appearance of the first arctic glacial-interglacial cycles. The cedar tree appears at Nador only at the end of the Piacenzian, at time of the first cooling, while it has been found punctually in Messinian and early Pliocene sediments of Habibas in Algeria and in Messinian sediments of the Bou Regreg section at Salé in Morocco. The regular presence of Cedar at Bou Regreg during the Messinian, allows supposing that it was present in the Middle Atlas Mountains and that its development was favoured by colder conditions.     

Integrated stratigraphy and paleoceanography of the Messinian (latest Miocene) across the North Atlantic Ocean

The Messinian was a time of major climatic and paleoceanographic change during the late Cenozoic. It is well known around the Mediterranean region because of the giant anhydrite/gypsum sequence and the suggested desiccation of the Mediterranean Sea. However, this interval is less constrained outside the Mediterranean region, where several paleoceanographic changes could have taken place because of the desiccation. Hence, we present an integrated stratigraphic framework for future Messinian paleoceanographic studies, determination of the effect of the Mediterranean desiccation on deep-water paleoceanography, and comparison of intra-Mediterranean paleoceanographic changes with those in the open oceans during the Messinian Stage.Four DSDP/ODP Holes (552A, 646B, 608, and 547A) from the North Atlantic Ocean and one land borehole from Morocco have been studied to integrate bio-, magneto-, and stable isotope Messinian stratigraphy with high resolution sampling. Our results produce the best assessment of the Tortonian/Messinian boundaries in all holes because they do not rely on any one signal.In paleomagnetic Subchronozone CSAn.lr in the Salé borehole and DSDP Site 609, a S/D coiling direction change of Neogloboquadrina pachyderma/acostaensis appears to indicate PMOW entering the northeastern Atlantic Ocean, at least reaching 50°N. Diachrony and synchrony of some important Messinian planktic foraminifera from these Atlantic DSDP/ODP holes and the Salé borehole, such as the LO of Gq. dehiscens, the LO of Gt. lenguaensis, the FO and LO of Gt. conomiozea, the FO of Gt. margaritae s.s., the FO of Gt. puncticulata, and the FO of Gt. crassaformis are discussed for understanding some of the paleoceanographic changes. This integrated stratigraphie framework presented here allows much better North Atlantic correlations at this critical point in Messinian geologic history.     

The Messinian marine molluscs record and the dawn of the eastern Atlantic biogeography

The biological impact of the Messinian Salinity Crisis (MSC) and its bearing on the Pliocene Mediterranean marine molluscan fauna has been analyzed on the basis of the biogeographic and stratigraphic distributions of the taxa of 16 early Messinian outcrops. The extinction of the last paleoendemic Proto-Mediterranean taxa is historically significant but it appears to be numerically less important than the extinction of the Tortonian and Messinian neoendemic taxa. The available data suggest that the MSC caused a regional mass disappearance but only a limited number of extinctions. It is also emphasized that the Late Pliocene (Monegatti et al., 2002) extinctions were far heavier than those caused by the MSC. We suggest that the greatest Messinian extinctions were triggered, during the salinity crisis, in the Atlantic “sanctuary” by the Messinian glacial events TG22, TG20, TG14, and TG12, of Shackleton et al. (1994), dated between 5.79 and 5.55 Ma by Krijgsman et al. (2004). A comparison between the Mediterranean Messinian and the Redonian molluscan faunas was also carried out. Finally, the possible latitudinal stability of the climatic thresholds, despite the shifting of the climatic zones throughout the Neogene along the European coast, is pointed out.     

Carbonate bioformations around underwater freshwater springs in the north-eastern Adriatic Sea

Large carbonate, bryozoan-serpulid constructions, made by Pentapora fascialis and Salmacina dysteri respectively, were found around karstic freshwater springs, called vruljas, in the Senj Archipelago (Velebit Channel, Croatia). In June 2002, several sites were investigated by SCUBA divers on the rocky cliffs of Grmac and dralova at depths ranging from 19 to 32 m. Mean colony diameter decreased with increasing distance from the vruljas: in the vicinity the mean diameter was 65.8±21 cm, at 2-m distance it was 40.4±8.2. Carbonate contribution was to a great extent due to the bryozoan (5,784±1,186 gm^–2 CaCO₃) rather than to the serpulid (383±218 gm^–2 CaCO₃). P. fascialis carbonate standing stock was remarkably high if compared with data from literature for shallow carbonate producers. The bryozoan-serpulid constructions can be indicated as important, even if localised, contributions to the carbonate budget in the Adriatic Sea.     

The mud mound nature of the Cassian Platform Margins of the Dolomites A case history: the Cipit boulders from Punta Grohmann (Sasso Piatto Massif, northern Italy)

Summary The sedimentological features and the microbiofacies of the Cassian platforms (Late Ladinian-Carnian) of the Dolomites can be studied only on the basis of the socalled “Cipit boulders”, that are platform-derived olistoliths and clasts fed to the basin and escaped to the extensive dolomitization affecting the buildups. Our paper deals with the Cipit boulders occurring in the Punta Grohmann section (Wengen and S. Cassiano formations, Late Ladinian, Archelaus and Regoledanus Zones). The dominant microfacies are represented by boundstone, consisting of nearly 60% of micritic limestone occurring both as peloidal or aphanitic micrite, mostly organized into stromatolitic laminites of thrombolites. The skeletal organism (Tubiphytes, skeletal cyanobacteria, sphinctozoan sponges, etc.) represent only a minor component of the rock (usually less than 10%). Early cements are widespread and consist both of fan-shaped calcite (replacing former aragonite), bladed isopachous magnesian calcite and radial-fibrous calcite (neomorphic after Mg-calcite). The carbonate platforms from which the olistoliths derive were made up mainly of carbonate mud that underwent early lithification, as witnessed by the considerable amount of early cements: therefore they may be regarded to as mudmounds, and more precisely as microbial mud-mounds, due to the clearly accretionary, organic-controlled nature of most micrites. The micrites, subdivided into auto- and allomicrite on the basis of micromorphological and fabric characteristics, have been tested for epifluorescence. The results confirm the organic control on the deposition of automicrite, also in the cases in which a microbial influence is not obvious (i.e. aphanitic micrite without internal organization).     

A microbial role in the construction of Mono Lake carbonate chimneys?

Lacustrine carbonate chimneys are striking, metre‐scale constructions. If these were bioinfluenced constructions, they could be priority targets in the search for early and extraterrestrial microbial life. However, there are questions over whether such chimneys are built on a geobiological framework or are solely abiotic geomorphological features produced by mixing of lake and spring waters. Here, we use correlative microscopy to show that microbes were living around Pleistocene Mono Lake carbonate chimneys during their growth. A plausible interpretation, in line with some recent works by others on other lacustrine carbonates, is that benthic cyanobacteria and their associated extracellular organic material (EOM) formed tubular biofilms around rising sublacustrine spring vent waters, binding calcium ions and trapping and binding detrital silicate sediment. Decay of these biofilms would locally have increased calcium and carbonate ion activity, inducing calcite precipitation on and around the biofilms. Early manganese carbonate mineralisation was directly associated with cell walls, potentially related to microbial activity though the precise mechanism remains to be elucidated. Much of the calcite crystal growth was likely abiotic, and no strong evidence for either authigenic silicate growth or a clay mineral precursor framework was observed. Nevertheless, it seems likely that the biofilms provided initial sites for calcite nucleation and encouraged the primary organised crystal growth. We suggest that the nano‐, micro‐ and macroscale fabrics of these Pleistocene Mono Lake chimneys were affected by the presence of centimetre‐thick tubular and vertically stacked calcifying microbial mats. Such carbonate chimneys represent a promising macroscale target in the exploration for ancient or extraterrestrial life.     

The Late Miocene coldspot of z-coral diversity in the Mediterranean: Patterns and causes

The Late Miocene distribution and diversity of zooxanthellate-like corals in the Mediterranean are analyzed in their paleobiogeographical framework, using our REEFCORAL database. The Late Miocene Mediterranean pool reached 20 z-coral genera. Although this fauna could build flourishing reef ecosystems during the Early Messinian, it was a relict fauna with severely limited speciation that lived on the edge of its ecological requirements in terms of solar energy and temperature range. Most z-coral genera, because they had long stratigraphic ranges and had survived previous extinctions, were able to adapt to the Messinian environments, which were unusual for such biotas. Hence, Porites, the most widespread genus in the region and also the most dominant in ecological assemblages, was the best equipped to cope with the drastic changes related to the Messinian Salinity Crisis.     

Facies characteristics and diversity in carbonate eolianites

Carbonate eolian dunes can form huge sand bodies along the coasts but are seldom described in the pre-Quaternary record. The study of more than 600 thin-sections collected in present-day, Holocene and Pleistocene dunes from Sardinia, Crete, Cyprus, Tunisia, Morocco, Australia and Baja California confirms that these deposits can be easily misinterpreted as shallow marine at core or thin-section scale. The classical eolian criteria (fine-grained and well-sorted sands) are exceptional in carbonate dunes because the diversity of shapes and densities of carbonate particles lowers the critical shear velocity of the sediment thus blurring the sedimentary structures. Wind carbonate deposits are mainly heterogeneous in size and often coarse-grained. The paucity of eolianites in the pre-Quaternary record could be due to misinterpretation of these deposits. The recognition should be based on converging sedimentological and stratigraphic elements at core scale, and diagenetic (vadose diagenesis, pedogenetic imprints) and petrographical (grain verticalization, scarcity of micritic envelopes, broken and/or reworked foraminifera) clues in thin-section. Bioclastic or oolitic grainstones showing evidence of vadose diagenesis or pedogenetic imprints, should always be suspected of having an eolian origin.