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1.
Controversies around the Messinian salinity crisis (MSC) are because of the difficulties in establishing genetic and stratigraphic relationships between its deep and shallow‐water record. Actually, the Sicilian foreland basin shows both shallow and deep‐water Messinian records, thus offering the chance to reconstruct comprehensive MSC scenarios. The Lower Gypsum of Sicily comprises primary and resedimented evaporites separated in space and time by the intra‐Messinian unconformity. A composite unit including halite, resedimented gypsum and Calcare di Base accumulated between 5.6 and 5.55 Ma in the main depocentres; it records the acme of the Messinian Salinity Crisis during a tectonic phase coupled with sea‐level falls at glacials TG14‐TG12. These deposits fully post‐date primary gypsum, which precipitated in shallow‐water wedge‐top and foreland ramp basins between 5.96 and 5.6 Ma. This new stratigraphic framework results in a three‐stage MSC scenario characterized by different primary evaporite associations: selenite in the first and third stages, carbonate, halite and potash salt in the second one associated with hybrid resedimented evaporites.  相似文献   

2.
Owing to its expanded stratigraphic sections, the Apennine thrust belt offers the opportunity to better understand the evaporitic and post-evaporitic Messinian events. A physical stratigraphic framework of Messinian deposits, based on facies analysis and basin-wide correlation of key surfaces and sedimentary cycles, is presented. It is shown that the Messinian Apennine foredeep had marginal basins with shallow-water primary evaporites and deeper basins where resedimented evaporites accumulated under relatively deep-water conditions. Like many other Mediterranean examples, primary shallow-water evaporites of Apenninic marginal basins show evidence for subaerial exposure and erosion. However, the development of such an erosional surface does not correspond to the deposition of primary evaporites in the deepest part of the basin(s); here, the unconformity can be traced towards the base of resedimented evaporites or to a level within them, implying that the deeper basins of the Apennine foredeep never underwent desiccation during the Messinian salinity crisis, but rather received the eroded marginal evaporites. This fact, usually overlooked, raises important questions about the deep desiccation model of the Mediterranean.  相似文献   

3.
Messinian evaporites, which resulted from the salinity crisis during the final closure of the Mediterranean Sea, are exposed in SE Turkey. These evaporites formed in two isolated sub-basins, Iskenderun-Arsuz (IA) and Hatay-Samanda? (HS), which belong to different depositional configurations and tectonic structures. The Neogene fill of these sub-basins consists of a thick sedimentary succession that started with Early Miocene terrestrial clastics, followed by reefs (Middle Miocene) and shallow water siliciclastics (Tortonian - Early to Late Miocene) and finally Messinian evaporates. These sub-basins accumulated in a diverse range of depositional environments from very shallow to deeper water. Evaporite facies in the IA sub-basin consist of sabkhas, saline lagoons and ponds. They are mainly represented by chemical deposits such as scattered gypsum nodules and balls, nodular bedded gypsum, laminated gypsum (Type-A) and selenites (Type-S1). Evaporites in the HS sub-basin mainly consist of detrital gypsum composed of gypsum laminae (Type-B, C), gypsum arenite-rudites and deeper water selenites (≤ 20 m), and resedimented selenites (Type-S2), which were deposited on a sulfate platform with a slope-basin transitional zone. Secondary gypsum with alabastrine and porphyroblastic textures as well as satin spar veins is commonly associated with the sabkha-type evaporites of the IA sub-basin. Deeper-water clastic evaporites of the HS sub-basin have generally remained as primary gypsum or have only been slightly affected by diagenetic alterations. The isotope values (87/86Sr; δ18O SMOW; and δ34S CDT) from the different kinds of gypsum lithofacies of the sub-basin are similar to those of the Messinian evaporites in other peri-Mediterranean basins, indicating an origin from marine water without external or basinal contributions.The Messinian evaporites examined in this paper are overlain by Early Pliocene (Zanclean) deposits composed of shallow- and deep-water siliciclastics and carbonates with local intercalations of Lago-Mare-type strata. Throughout the Messinian evaporitic stage, the IA sub-basin was mainly comprised of shallow water evaporites, while the HS sub-basin underwent deepening related to regional tectonics induced by the Dead Sea Fault during the construction of the Hatay Graben.  相似文献   

4.
The Messinian Salinity Crisis (MSC) resulted from a significant multi-phase drop and subsequent reflooding of the Mediterranean Sea from 5.96 to 5.33 Ma. Well-developed drainage networks, characterized by step-like profiles and abrasion platforms, are associated to this event. The Ebro Continental Margin (Western Mediterranean) presents an additional complexity since the capture of the drainage of the adjacent subaerial Ebro Basin took place sometime prior to the Messinian stage. Using 3D seismic reflection data, this work provides new insights into the origin of the step-like profile of the Messinian erosional surface (MES) and timing of the capture of the subaerial Ebro Basin. The results obtained indicate a sedimentary-active continental slope and delta progradation during Middle-Late Miocene, in a normal regressive context associated to a pre-Messinian proto-Ebro River. The mature development attained by the Messinian Ebro River network during the MSC corroborates that the capture of the Ebro Basin occurred prior to the MSC. The configuration of the clinoforms below the MES suggests that deltaic sediments of the Messinian Paleo-Ebro River deposited during the Tortonian and initial Messinian sea-level drawdown. The MES formed at the top of the Tortonian Highstand, where a fluvial network was deeply carved, and in the topset region of the Messinian Falling Stage Systems Tract, where minor erosion occurred. Fluvial deposits are outstandingly preserved on the main valleys of the MES. Therefore, the step-like profile of the MES was not created during Zanclean inundation, but during the latest stages of the main Messinian sea-level fall and lowstand.  相似文献   

5.
A new genetic facies model for deep-water clastic evaporites is presented, based on work carried out on the Messinian Gessoso-solfifera Formation of the northern Apennines during the last 15 years. This model is derived from the most recent siliciclastic turbidite models and describes the downcurrent transformations of a parent flow mainly composed of gypsum clasts. The model allows clearer comprehension of processes controlling the production and deposition of clastic evaporites, representing the most common evaporite facies of the northern Apennines, and the definition of the genetic and stratigraphic relationship with primary shallow-water evaporites formed and preserved in marginal settings. Due to the severe recrystallization processes usually affecting these deposits, petrographic and geochemical analyses are needed for a more accurate interpretation of the large spectrum of recognized gravity-driven deposits ranging from debrisflow to low-density turbidites. Almost all the laminar ‘balatino’ gypsum, previously considered a deep-water primary deposit, is here reinterpreted as the fine-grained product of high to low-density gravity flows. Facies associations permit the framing of the distribution of clastic evaporites into the complex tectonically controlled depositional settings of the Apennine foredeep basin. The Messinian Salinity Crisis occurred during an intense phase of geodynamic reorganization of the Mediterranean area that also produced the fragmentation of the former Miocene Apennine foredeep basin. In this area, primary shallow-water evaporites equivalent to the Mediterranean Lower Evaporites, apparently only formed in semi-closed thrust-top basins like the Vena del Gesso Basin. The subsequent uplift and subaerial exposure of such basins ended the evaporite precipitation and promoted a widespread phase of collapse leading to the resedimentation of the evaporites into deeper basins. Vertical facies sequences of clastic evaporites can be interpreted in terms of the complex interplay between the Messinian tectonic evolution of the Apennine thrust belt and related exhumation–erosional processes. The facies model here proposed could be helpful also for better comprehension of other different depositional and geodynamic contexts; the importance of clastic evaporites deposits has been overlooked in the study of other Mediterranean areas. Based on the Apennine basins experience, it is suggested here that evaporites diffused into the deeper portions of the Mediterranean basin may consist mainly of deep-water resedimented deposits rather than shallow-water to supratidal primary evaporites indicative of a complete basin desiccation.  相似文献   

6.
The salinity crisis of the Mediterranean during Messinian time was one of the most dramatic episodes of oceanic change of the past 20 or so million years, resulting in the deposition of kilometer thick evaporitic sequences. A large and rapid drawdown of the Mediterranean water level caused erosion and deposition of non-marine sediments in a large ‘Lago Mare’ basin. Both the surface loading by the Lower Messinian evaporites, and the removal of the water load resulted in isostatic/flexural rebound that significantly affected river canyons and topographic slopes. We use flexure models to quantitatively predict possible signatures of these events, and verify these expectations at well-studied margins. The highly irregular shape of the reconstructed basin calls for a three-dimensional model. Near basin margins, plate-bending effects are most pronounced which is why flexure is particularly important for a relatively narrow basin like the Mediterranean. We focus on one specific sea level scenario for the Messinian Salinity Crisis, where most of the evaporite load was deposited during a sea level highstand, followed by a rapid desiccation. Evaporite loading at current sea level is expected to cause subsidence of the deep basins by hundreds of meters and simultaneous uplift of continental parts of the margins. Differential uplift may lead to significant slope angle changes and thus gravity flows. The relative scarcity of Lower Evaporite sequences along the margins may be a result of these phenomena. Normal faulting of Lower Evaporite and older sediments and rocks is expected on the margins. Desiccation enhances erosion of the freshly exposed continental shelf and slope. Subsidence and riverbed sedimentation occurs on the continental margins, and significant uplift towards the basin center. Reverse faulting is predicted at the margins. Finally, regional isostatic uplift following Zanclean flooding is predicted to destabilize margin slope deposits, and to cause marginal uplift, river down-cutting, and normal faulting.  相似文献   

7.
《Geodinamica Acta》2013,26(1-3):29-40
In the Tertiary Basin of Piedmont (Northern Italy) a 100-150 m thick Messinian sedimentary succession crops out, composed of pre-evaporitic clays, gypsum beds and post-evaporitic lacustrine-marine fine-grained sediments. In the Monferrato area the thickness of the evaporite sequence is highly variable (0-140 m) due to an important erosion surface formed at the end of the evaporite cycle and carved in the gypsum beds. Epigenic caves probably formed during this short intra-Messinian phase of emersion. Cave sediments contain benthonic and planctonic foraminiferal associations ranging in age from Burdigalian to Upper Pliocene. These sediments have probably been deposited in recent times, although it cannot be completely ruled out that they accumulated in caves developed in Upper Messinian times. The formation of the most important caves of this area probably started at the end of the Messinian under epigenic conditions. Possibly, those inherited caves enlarged slowly during the Quaternary in an intrastratal and confined hypogene karst system.  相似文献   

8.
This study represents a preliminary investigation of the late Messinian subsurface Marsa Zouaghah Formation in the Western Libyan Offshore, Central Mediterranean Sea. The formation was deposited in three major environmental settings: (a) Marginal Sabkha; (b) Open Lagoon; and (c) Hypersaline Lagoon. The marginal sabkha and open lagoonal settings are locally interrupted by intertidal oolitic shoal deposits. The marginal sabkha facies is replaced in central parts of the Libyan offshore by a narrow zone of aeolian-fluvial facies, the distribution and thickness of which is entirely controlled by a local uplift, the Tripoli Nose'. The marginal sabkha facies broadly defines the late Messinian palaeoshoreline lying parallel to, and north of, the E-W Jifarah fault system which dominated the southern part of the Libyan offshore. This fades is, thus, interpreted as being structurally controlled by fault systems. The hypersaline lagoonal facies is developed in areas of relatively higher rates of subsidence than that of adjacent facies belts. It is therefore, related to restriction formed by continuous subsidence and evaporation. The Marsa Zouaghah Formation constitutes saltern evaporates deposited over a wide platform in sabkha and lagoonal settings, forming part of the 'basin-wide-evaporites' of the Mediterranean Basin deposited during the Messinian salinity crisis. The evaporites formed during a major relative sea-level fall within a subsiding basin situated on the northern continental margin of the African plate. Local, vertical and lateral variations in lithofacies and thickness within the Messinian deposits of the north-west Libyan offshore were controlled by contemporaneous strike-slip movements in addition to sea-level change.  相似文献   

9.
The Messinian sediments of northeastern Tunisia were deposited under an active tectonic setting. They are organized in sequences indicating a transitional deposit from margin – littoral to lacustrine – continental facies. These series unconformably overlie the Serravallian–Tortonian silty clays packages, and are overlain by the transgressive Early Pliocene marl (Zanclean). The presence of evaporitic strata points out to the Messinian Salinity Crisis described in the peripheral basins of the western Mediterranean. The Messinian sedimentation was found to have been closely controlled by transtensive tectonics and differential subsidence at a large spatio-temporal scale. It is organized in sequences typical of a depositional environment controlled by eustatism, tectonic and maybe by climate changes. Despite the existence of some local specific sedimentological characteristics, our results corroborate previous findings that pointed out to the Messinian times as a singular period all around the Mediterranean Basin. Field and subsurface seismic profile data helped reconstructing either the sedimentary or tectonic unconformities existing between the studied Messinian series and older Neogene successions.  相似文献   

10.
The ongoing debate about the Messinian salinity crisis in the Mediternean is fuelled in part by the lack of an adequate time control. The most accurate and, at the same time, detailed constraints are nowadays provided by the astronomical dating technique. Here we present an astronomical age model for the cyclically bedded Tripoli diatomite Formation on Sicily (pre-evaporite Messinian, Italy) based on an integrated stratigraphic study of three key-sections, Falconara, Gibliscemi and Capodarso. Characteristic sedimentary cycle patterns allow (i) the sections to be cyclostratigraphically correlated, the 'bed-to-bed' correlations being confirmed by high-resolution planktonic foraminiferal biostratigraphy, and (ii) the Tripoli cycles to be calibrated to the astronomical record. Despite minor misfits the correctness of the tuning is evident from the match between precession-obliquity interference in the astronomical target and its reflection in the sedimentary cycle record. The tuning provides absolute astronomical ages for all sedimentary cycles and planktonic foraminiferal events. The base of the Tripoli is astronomically dated at 7.005 Ma, indicating that the onset of diatomite formation is diachronous in the Mediternean since it started 300 000 years earlier on Sicily than on Gavdos, south of Crete. The top of the Tripoli, and thus the onset of the salinity crisis proper on Sicily, arrives at 5.98 Ma.  相似文献   

11.
Astronomical tuning of the Messinian pre‐salt succession in the Levant Basin allows for the first time the reconstruction of a detailed chronology of the Messinian salinity crisis (MSC) events in deep setting and their correlation with marginal records that supports the CIESM ( 2008 ) 3‐stage model. Our main conclusions are (1) MSC events were synchronous across marginal and deep basins, (2) MSC onset in deep basins occurred at 5.97 Ma, (3) only foraminifera‐barren, evaporite‐free shales accumulated in deep settings between 5.97 and 5.60 Ma, (4) deep evaporites (anhydrite and halite) deposition started later, at 5.60 Ma and (5) new and published 87Sr/86Sr data indicate that during all stages, evaporites precipitated from the same water body in all the Mediterranean sub‐basins. The wide synchrony of events and 87Sr/86Sr homogeneity implies inter‐sub‐basin connection during the whole MSC and is not compatible with large sea‐level fall and desiccation of the Mediterranean.  相似文献   

12.
The Melilla carbonate complex (NE Morocco) is the only area of the Paleo-Mediterranean Sea where volcanic activity was present throughout most of the Messinian. 40Ar/39Ar dating of volcanic tuffs interbedded within the upper Messinian sedimentary deposits, known as the Terminal Carbonate Complex (TCC), yields accurate ages of paleoenvironmental and sea-level changes related to the Messinian Salinity Crisis. The new chronologic data (1) provide an average of 5.95–5.99 Ma for the base of the TCC, thus being synchronous with the onset of the Messinian Salinity Crisis, (2) demonstrate for the first time that the basal unconformity of the TCC does not represent a hiatus of long duration, (3) define a precise time line at 5.87±0.02 Ma (2σ) corresponding to sedimentary rocks exhibiting a lateral transition between continental and marine deposits typical of the TCC and (4) yield evidence that emersion of the Melilla platform during deposition of the TCC is partly related to tectono-magmatic activity. An erosional surface, capping the TCC deposits in the Melilla basin, is related to the major Messinian Mediterranean drawdown. The duration of the hiatus, associated with this surface, is estimated to be at most 450 kyr, but is probably shorter.  相似文献   

13.
We present the results of a study of the Vena del Gesso Basin (Romagna Apennines, Italy) integrating field analyses and analogue modelling. This basin represents one of the best‐preserved top‐thrust basins in the Northern Apennines foreland and is one of the few examples where primary evaporites, related to the Messinian salinity crisis of the Mediterranean, widely crop out. The structural style affecting the Messinian gypsum is examined to get insights into the mechanism responsible for the overall deformation features recognizable in the area. The evaporites are completely detached at the base and widespread back‐thrusts, repeatedly doubling these deposits, strongly contrast with the regional forelandward vergence of structures in the Apennines. On the basis of the comparison between field data and experimental results, the features characterising this area can be described as the result of the deformation linked to the sequential activation of an obliquely propagating passive‐roof duplex. Analogue models evidenced the major role played (1) by syntectonic erosion that promoted the development of passive‐roof duplex style, as well as (2) the role of décollement level pinch‐out that determined an oblique progression of deformation. Finally our data lead to reconsider the palaeoenvironmental reconstruction concerning the onset of the Messinian salinity crisis in the Mediterranean. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

14.
The Sorbas Member is a late Messinian complex sedimentary system that formed immediately following deposition of the Messinian evaporites in the Sorbas Basin (South‐east Spain). This work describes the sequence architecture and facies organization of a continuous kilometre long, alluvial fan to open platform transect near the village of Cariatiz in the north‐east of the basin. The post‐evaporitic Cariatiz platform was a mixed carbonate‐siliciclastic system composed of four intermediate‐frequency, fifth‐order depositional sequences (Depositional Sequences 1 to 4) arranged in an overall prograding trend. The intense fracturing and brecciation of these deposits is attributed to the deformation and dissolution of an evaporite body measuring several tens of metres in thickness. The four sequences display significant spatial–temporal variability in both architecture and facies distribution, with two main phases: (i) Depositional Sequences 1 and 2 are ooid and oobioclastic dominated, and show normal marine faunas; and (ii) Depositional Sequences 3 and 4 show a higher siliciclastic contribution and are microbialite dominated. These important changes are interpreted as modifications of the primary controlling factors. Following an initial 70 m drowning, possibly linked to increased oceanic input, Depositional Sequences 1 to 3 were controlled mainly by eustatic variations and inherited topography; their progradation destabilized the evaporite body near the end of the Depositional Sequence 2 period. During the second phase, Depositional Sequences 3 and 4 recorded a progressive restriction of the Sorbas Basin related to a 30 to 40 m fall in water level that was driven mainly by regional factors. These regional factors were dissolution and gravity‐induced deformation of the evaporites and correlative evaporative fluid circulation associated with the contrasted arid/humid regional climate that, respectively, controlled sequence geometry and fluctuating water salinity which caused a microbialite bloom.  相似文献   

15.
Various workers have suggested that the Upper Miocene (Messinian) evaporites of the Sicilian Basin formed in a topographic basin of considerable relief, filled with hypersaline water. Our studies indicate that this basin contained shallow water, at least during the deposition of the carbonate rocks intercalated between the gypsum beds. We recognize four basic kinds of limestone: (1) pelletal and pisolitic limestone; (2) skeletal limestone; (3) oöitic limestone, and (4) laminated lime-stone-dolostone. Modern analogs suggest that three of these four kinds of carbonate must have formed close to or above sea level. The evidence supporting this contention includes pellets with algal coatings, pisolites, quiet-water oöids, and algal laminates. Therefore we suggest that the evaporites associated with these carbonates may likewise have formed in relatively shallow water. An alternative conclusion would be that the level of the sea, and the salinity, underwent irregular patterns of profound change.  相似文献   

16.
《Comptes Rendus Geoscience》2014,346(3-4):90-98
New field and micropalaeontological investigations have been conducted in four of the Pliocene rias of the internal zone of the Rif in Morocco, on the southern margin of the Alboran Sea. We found that marine sediments outcropping in these rias were deposited mainly during the Early Zanclean, between 5.04 and 3.8 Ma. After a transgressive episode that led to the deposition of terrestrial to marine conglomerates, dark clays deposited first at shallow palaeo-depths and then at bathyal palaeo-depths. The rias were then infilled with a shallowing upward succession comprising marine clays and sandstone and, locally, terrestrial sediments that indicate their final emersion. No Gilbert-deltas were observed in these rias. The presence of transgressive deposits at the bottom of the rias, also identified in other basins of the external zone of the Rif, and the absence of Gilbert deltas question a catastrophic reflooding after the Messinian Salinity Crisis in this area.  相似文献   

17.
Messinian evaporites in Cyprus resulted from the interplay of Mediterranean-wide and eustatic sea-level changes and local tectonics, in an inferred above-subduction zone setting. Distinctive Tortonian-early Messinian pre-evaporitic facies include diatomaceous marls and microbial carbonates, overlain by a variety of gypsum facies and then by lagoonal-lacustrine deposits and local palaeosols. Facies analysis and comparisons allow construction of a simple model, in which evaporites formed in semi-isolated small basins not far below global eustatic sea-level. Coarsely crystalline gypsum formedin situ along the margins of small basins and within shallow-water lagoons (< 10 m deep); this comprised common banded-stacked (i.e. layered) selenite, swallowtail selenite, botryoidal selenite and sugary-bedded selenite. Fine-grained gypsum precipitated widely and was reworked into basinal areas (< 70 m deep) by weak traction currents and low-density turbidity currents. Shallow-water derived selenite was also reworked basinwards by high-density turbidity currents and debris flows. Slumps indicate tectonic instability. More detailed basin analysis can be achieved by study of individual sub-basins. In the Polemi sub-basin in the west, a Lower Unit (up to 60 m thick) comprises basinal gypsum, interbedded with gypsum turbidites and mass flow deposits, with slumps. This is overlain by an extensive mega-rudite (up to 20 m thick) including up to metre-sized clasts of marginal gypsum facies. Above, the Upper Unit (up to 70 m thick) includes shallow-water gypsum (e.g. swallowtails), marl and minor microbial carbonates. The Pissouri sub-basin in the south-west exposes marginal facies of the Upper Unit, including deltaic elastics and palaeosols. The Maroni sub-basin in the south exhibits a basinal lower gypsum unit, with laterally equivalent marginal facies (up to 50 m thick), overlain by an extensive mega-rudite (up to 20 m thick). Finally, the Mesaoria subbasin in the north exposes relatively marginal gypsum facies in an unstable tectonic setting. Formation of the Polemi, Pissouri and Mesaoria gypsum sub-basins relates to coeval extensional faulting and graben development. Evaporites in south Cyprus (Maroni sub-basin) formed in elongate basins between former compressional lineaments created by localized Early Miocene thrusting. In the sub-basins of west, south-west and south Cyprus, large-scale slumping of marginal gypsum facies took place towards depocentres (to form megarudite debris flows), triggered by one or several phases of extensional faulting.  相似文献   

18.
The Marche Apennines (Italy) offer an excellent opportunity to constrain the temporal and spatial relationships between drainage network formation and tectonic activity. Using a combination of field data, seismic lines and boreholes we show that the main deformation phase took place during the Messinian when the area, affected by the Messinian sea level drop, emerged and evolved from marine to continental conditions. The results highlight that during the Messinian emersion a drainage network developed contemporaneously with an increase in tectonic activity that could be related to sea level fall and river erosion. The present‐day river system, which is dominated by transverse rivers that cut straight across the tectonic grain, is located in older Messinian palaeovalleys, even though the region was subsequently covered by water until the late Pliocene–early Pleistocene.  相似文献   

19.
We propose a revised age calibration of the Messinian salinity crisis onset in the Mediterranean at 5.971 Ma based on the recognition of an extra gypsum cycle in the transitional interval of the Perales section (Sorbas basin, Spain) and the revision of the magnetostratigraphy of the Monticino section (Vena del Gesso basin, Italy). This age re‐calibration allows to state more accurately that: (i) the interval encompassing the MSC‐onset is continuous, thus ruling out any erosional feature or stratigraphic hiatus related to a major sea‐level fall affecting the Mediterranean; (ii) the first gypsum was deposited during the summer insolation peak at 5.969 Ma associated with an eccentricity minimum and roughly coincident with glacial stage TG32; (iii) the MSC‐onset was preconditioned by the tectonically‐driven reduction of the hydrological exchanges with the Atlantic Ocean and finally triggered by glacial conditions in the northern hemisphere and by arid conditions in northern Africa.  相似文献   

20.
How the Messinian Salinity Crisis (MSC) ended is still a matter of intense debate. The Terminal Carbonate Complex (TCC) is a late Messinian carbonate platform system that recorded western Mediterranean hydrological changes from the final stages of evaporite deposition till the advent of Lago-Mare fresh- to brackish water conditions at the very end of Messinian times. A multidisciplinary study has been carried out in three localities in south-eastern Spain to reconstruct the history of TCC platforms and elucidate their significance in the MSC. Overall, this study provides evidence that the TCC formed following a regional 4th order water level rise and fall concomitant with an opening-restriction trend. It can be subdivided into four 5th order depositional sequences (DS1 to DS4) recording two phases: (1) from DS1 to DS3, a tide-dominated ooidic to oobioclastic system with stenohaline faunas developed as a result of a 70 m water level rise. During this period, the TCC developed in a shallow sea with close to normal marine salinity; (2) in depositional sequence 4, a microbialite-dominated platform system developed. This is indicative of a significant environmental change and is attributed to a 30 to 40 m water level fall in the basins under study. These restricted conditions were coeval with intense evaporite deformation and brine recycling. The syn-sedimentary deformation of evaporites had a major impact on platform architecture and carbonate production, affecting the Messinian series throughout south-eastern Spain at the end of the TCC history. At that time, the TCC developed in a lake with fluctuating, brackish- to hypersaline water. These findings suggest a temporary restoration of marine conditions in the western Mediterranean marginal basins due to Atlantic water influxes prompted by a global sea level rise around 5.6 Ma. Whether marine conditions extended to the entire western Mediterranean still needs to be investigated.  相似文献   

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