Sedimentary Geology 188ndash189 (2006) 1ndash8wwwelseviercomlocatesedgeo

Editorial

The Messinian Salinity Crisis revisited

1 General background

Knowledge of the Messinian Salinity Crisis (MSC)increased in the last decade due to the availability of arefined magneto- and bio-stratigraphy and as a conse-quence of an accurate astronomically-tuned time scalewhich provided a powerful tool for high resolutioncorrelation of the environmental changes through thedifferent Mediterranean areas and between the Mediter-ranean and the global record (Gautier et al 1994Benson et al 1995 Hilgen et al 1995 Krijgsman et al1995 Sprovieri et al 1996 Hilgen and Krijgsman1999 Krijgsman et al 1999 Hodell et al 2001 Vidal etal 2002 among many other papers) The Messinianscientific adventure was initiated in 1970 by the drillingof the Deep Sea Drilling Project (DSDP Leg 13 Ryan etal 1973) that revealed the existence of this giantevaporitic event stimulating an unusual quantity of re-searches and generating lively and even conflictingdebates During about 25 years scientific harvest wasconsiderable and discussion exceptionally active Aseries of meetings specifically devoted to the MessinianSalinity Crisis and its consequences was initiated in1973 by CW Drooger (Messinian Events in theMediterranean) and followed by a succession ofsymposia and workshops organized at the initiative ofMB Cita on different topics related to the salinity crisisThe results were thus regularly updated and discussedand provided to the scientific community as specialissues of scientific journals dedicated respectively to theMessinian events in the Mediterranean (Drooger 1973)the Biodynamic effects of the Messinian Salinity Crisis(Benson 1976) the Messinian evaporites (Catalano etal 1978) the Messinian Erosional Surfaces in theMediterranean (Cita and Ryan 1978) the Geodynamicand biodynamic effects of the Messinian salinity crisis inthe Mediterranean (Cita and Wright 197980) and the

0037-0738$ - see front matter copy 2006 Elsevier BV All rights reserveddoi101016jsedgeo200602003

Geodynamical aspects of the MessinianPliocene bound-ary (Orszag-Sperber and Rouchy 1980) Till the DSDPLeg 42 (Hsuuml et al 1978a) the interpretation of thesalinity crisis was marked by strongly opposed ideaswhich were mostly focused about the initial depth of thebasin and the depth of evaporite deposition but after thisleg the updated version of the model of deep basinshallow water deposition initially proposed by Hsuuml et alin 1973 (Cita et al 1978 Hsuuml et al 1978b) received awide acceptance among the specialized community andoutside although differences persisted on some aspects(Rouchy 1982 Benson and Rakic-el Bied 1991Rouchy and Saint Martin 1992) In the same timeintensive research studies were carried out on theperipheral basins generally based on multidisciplinaryapproaches and offshore where seismic investigationsprovided new insights on the deep evaporite successionsand their relations to the erosional surface(s) andmarginal deposits Three ODP legs although not directlyfocussed on the question of the salinity crisis took placerespectively in the Tyrrhenian Sea (Leg 107 Kastens etal 1990) the Eastern Mediterranean (Leg 160 Robert-son et al 1998) and Western Mediterranean (Leg 161Zahn et al 1999)

Since the middle of the 1990s magnetostratigraphicstudies done both out of the Mediterranean Basin andwithin the new astronomical time-scale and thedevelopment of high-resolution multi-proxy approachesre-stimulated the researches on the MSC and reactivatedthe debate about its interpretation with new lively andstill conflicting discussions Four new scenarios wereproposed which questioned most of the key points of theprevious models (Butler et al 1995 Clauzon et al1996 Riding et al 1998 Krijgsman et al 1999) Thedebate that was formerly centred on the depth of thebasin and evaporite deposition shifted hence toward thechronology of the major events the depositional settings

2 Editorial

of the evaporites and the environmental changes throughthe late MessinianEarly Pliocene transition In contrastto the precedingmodels that were based on two steps thataffected successively the whole Mediterranean themodels proposed by Butler et al Clauzon et al andRiding et al assume the complete diachronism of theevaporite deposition in the deep and the marginal basinsThe diachronism is maximum for Clauzon et al forwhom desiccation occurred first in the shallow marginalbasins (marginal evaporites) before reaching the deepbasins (deep almost desiccated basin evaporites) ForButler et al the diachronism affected only the lowerevaporites while Riding et al assume the evaporites tookplace first in the deep basins before a marine refloodingduring which evaporites formed in the marginal basinsIn contrast the chronology of the model of Krijgsman etal is in good agreement with that of the previous models(Hsuuml et al 1973 1978b Cita et al 1978 Montadert etal 1978 Rouchy 1982 Benson and Rakic-el Bied1991 Rouchy and Saint Martin 1992) but it differs onthe depositional conditions of the lower evaporites thatare considered to have been formed in deep marineconditions followed by a short desiccation before thedeposition upper evaporites assimilated to the Lago-Mare event Hardie and Lowenstein (2004) re-inter-preted also the deposition of the salt trapped in the deepbasin as deep water evaporites although it seems that forthe authors ldquodeeprdquo is used in the sense of ldquosubaqueousrdquorather than really deep as they precise that thedepositional depth may have been ldquofrom tens hundredsor perhaps even thousands of meters deeprdquo Anotherhighly debated question deals with the latest MessinianLago-Mare event that has different meaning for theauthors It was usually thought as the sedimentaryinterval comprised between the top of the evaporites andthe marine restoration with sometimes a part of the upperevaporites interval characterized by the presence of atypical brackish to freshwater fauna with Paratethyanimmigrants Krijgsman et al (1999) included the wholeupper evaporites within the Lago-Mare but Clauzon et al(2005) redefined the term of Lago-Mare as the intervalsthat contain fauna (molluscs andor ostracods) andorflora (dinoflagellate) of Paratethyan origin and suggestedthe occurrence of three Lago-Mare events Thesedifferent meanings are superimposed to strongly op-posed views about the depositional significance of theLago-Mare settings In agreement with the previousmodel one group maintains that this event records aregional dilution at the Mediterranean scale that caninclude the Upper evaporites (Krijgsman et al 1999)Another group believes the Lago-Mare facies reflectsonly local influence of freshwater inputs in verymarginal

settings along the edges of the Mediterranean that wouldhave already been reflooded by marine waters (Riding etal 1998) For Clauzon et al (2005) two of the Lago-Mare events correspond to brief episodes of global highsea-levels that allowed connections and exchangesbetween the Mediterranean Sea and Paratethys Thishas important implications regarding the timing andmagnitude of the sea level fluctuations as well as themechanism of restoration of the marine conditions in theMediterranean When did the re-opening of the connec-tions with the Atlantic happen and what was themechanism responsible for After a long perioddominated by the idea that the marine inundation wasthe consequence of the tectonic opening of the Gibraltargate and for some authors of a rise of the world sealevel the debate was completely renewed by theproposition that the opening could have been causedby the regressive erosion of a stream flowing along theemergedMediterranean side of the Gibraltar isthmus thatended by capturing the Atlantic waters (Blanc 2002)

These are some of the most debated questions thatraised during the two past decades They were exposedin a great number of papers sometimes very innovativethat proved the vitality of the scientific communityinvolved in the study of the Messinian Salinity CrisisHowever they highlight the great divergences that aroseamong the community about the interpretation of thevarious aspects of the MSC divergences that finallybecame much deeper than during the first period Thuswe thought that it was a timely moment to organize anew international colloquium to set up a broadinternational forum specifically devoted to the salinitycrisis 7 years after the two last meetings that held inSicily in 1997 respectively in Palermo and Catania Wetook the opportunity of the end of a research projectsupported by the programme ECLIPSE of the FrenchCNRS under the leadership of J-P Suc and JMRouchy to organize this colloquium in Corsica in July2004 The colloquium was also an interim-colloquiumof the Regional Committee of the MediterraneanNeogene Stratigraphy (RCMNS) and received a supportof the European Science Foundation (ESF) through theEEDEN Programme The aim of the colloquium was topresent an update of the recent and most significantadvances on the question of the Messinian SalinityCrisis to debate of the recent genetic models and todiscuss the perspectives for forthcoming investigationsbut also to promote dialogue between teams of differentcountries and stimulate cooperation between them Themeeting attracted 87 participants from 11 countriesgiving rise to 97 oral or poster presentations from whichthe papers included in this volume are coming excepted

3Editorial

for an external invited paper (Lu and Meyers) In factthis issue gathers the papers which are mostly focusedon the geological aspects of the crisis while a secondspecial issue published by Geobios will be morespecifically devoted to paleobiological aspects

2 Summary of contents

Altogether these papers present a good overview ofthe current state of knowledge of the Messinian SalinityCrisis in its different aspects including the geodynamicalcontext new interpretative scenarios regional studiesand their global impact the deep marine record thequestion of the Lago-Mare the MediterraneanndashPara-tethys exchanges and the modelling

The opening paper of the volume by Jolivet et al ismainly concernedwith a review of the role of the tectonicfactors that are of crucial importance as they caused theisolation and shaped the size and morphology of thereceptacle for evaporite deposition as well as themodification of the basin paleogeography through theMessinian In the recent years several papers proposedto interpret the closure as the consequence of deep crustalprocesses These different aspects are discussed in thispaper that emplaces the Messinian Salinity Crisis withinthe tectonic and paleogeographic evolution of theMediterranean region from the Oligocene to the PresentThe isolation of the Mediterranean resulted from aprogressive process that started some 30ndash35 Myr agoFor the authors it took place after the end of the late-orogenic extension in the Alboran domain and at theonset of a new stage of NndashS compression and was notrelated to the slab retreat that would have rather delayedthe onset of the MSC

The second paper byRouchy and Caruso is mostly areview paper that provides an updated re-examination ofthe most salient features of the MSC and hydrologicalrequirements for evaporite deposition in order to assessthe viability of the new models and to built an integratedscenario The proposed scenario is in good agreementwith the key-points of the previous models but with newstatements about the chronology depositional settingshydrological mechanisms consequences and correla-tions with the global changes Here the two main stagesof evaporite deposition affected successively the wholebasin with a slight diachronism between shallow anddeep areas The isolation has been controlled predom-inantly by tectonic processes but changes of the worldsea level and regional climate interfered to explain thecomplex development of the evaporitic crisis Severalepisodes of enhanced erosion coeval with the majorevaporitic steps are merged on the margins to form a

major erosional surface and the crisis The crisis endedby a general dilution at the Mediterranean scale beforethe sharp restoration of the marine conditions in theearliest Zanclean

Two papers deal with the seismic record of the evap-orites along the offshore margins of the deep basins atthe transition with the deep evaporites respectively inthe Gulf of Valencia and on the eastern side of the Levantbasin

In the Valencia Basin Maillard et al describe indetail the relations between the evaporites the erosionalsurfaces and related clastic deposits and propose acorrelation between erosions sea level variations andevaporite deposition The authors provide evidence oftwo major erosional surfaces which are bracketing theevaporite succession respectively at its base and top andmerge marginward in a single surface The basal surfaceextends into the Central Valencia Basin and the detritalproducts produced by the erosion grade laterally into themassive salt of the deep Provenccedilal Basin indicating thatan important sea-level fall occurred as soon as thebeginning of the Messinian Salinity Crisis Theoverlying Upper Evaporites unit display a transgressivepattern towards the margins where they onlap the basalsurface They are truncated at the top by a network ofincisions interpreted as a final erosional episode linkedto the Lago-Mare event

From the study of a series of 2D and 3D seismiclines Bertoni and Cartwright provide a characteriza-tion and mapping of the evaporites in the southeasternpart of the Levant margin and show their distributionand architecture are mostly constrained by structural anderosional features A series of structural highs related toanticlines of the Syrian Arc foldbelt formed a barrier thatcontrolled the overall landward extension of theevaporites Submarine canyons (Afiq El Arish andAshdod Canyons) which were active at least since theOligocene represented preferential sites of erosion andevaporite deposition explaining the irregular geometryof the edge of the evaporites characterized by majorembayments and landward outliers

The next group of three papers are field-based studiesin the Betic basins which have important implications ata regional scale as the first two papers by Lu and Meyersand Braga et al lead to the proposition of differentinterpretative scenarios and the third paper by Krijgsmanet al addresses the controversial question of whether theevaporite deposition was controlled by eustatic sea-levelchanges or by tectonics

From the analysis of the depositional facies andfabrics of the Messinian gypsum and associated depositsin the Nijar basin Lu and Meyers reconstruct the

4 Editorial

evolution of the depositional paleodepths throughout theevaporitic event The gypsum deposited continuously insubaqueous conditions with water depth commonly near10ndash30 m and occasionally up to 100 m or deeperAlthough two major drops with a magnitude of sim140 moccurred before and after the deposition of Yesaresevaporites the basin never desiccated Depth fluctua-tions around 50ndash80 m of magnitude which occurred inrelation with the deposition of alternating gypsum andmarls are thought to be the result of glacio-eustaticfluctuations These data lead the authors to suggest ascenario for the Messinian event in which the evaporitesformed in two steps that affected successively the wholeMediterranean but in which the evaporites formed inldquodeeprdquo water conditions rather than during the desicca-tion of the basin

By the study of the sedimentary record in the SorbasAlmeriacutea-Niacutejar and Vera basins Braga et al provide newarguments for the model they proposed about 10 yearsago (Riding et al 1998) In this model these basinsremained connected with the Mediterranean throughoutthe Messinian except during a major desiccation phaserelated to salt deposition in the deep basin of theWesternMediterranean that occurred abruptly at the beginning ofthe crisis The sea level fall caused the erosion of the pre-evaporitic marine deposits (Yesares Member) and wasfollowed during the late Messinian by the restoration ofsea-levels as high as those that preceded the desiccationThe deposition of the gypsum of the Betic basins post-dates the salt formation and formed in marginal silled-basins during the marine reflooding prior to theMessinianndashZanclean boundary In this scenario the sig-nificance of the Lago-Mare facies is restricted to verylocalized continental settings adjacent to the Mediterra-nean Sea

In their paper Krijgsman et al investigate whichof the tectonic uplift or sea level lowering wasresponsible for the deposition of the Tortonianevaporites of the Eastern Betics Using a multidisci-plinary approach combining biostratigraphy magne-tostratigraphy and isotopic datings they obtain a highresolution chronology for the Venta de la Virgensection in the MurciandashCartagena Basin The resultsand the correlation with the Sorbas Basin demonstratethat the dominant factor was the local tectonic activitywhile eustatic sea-level changes had minor influenceCoeval uplift of the MurciandashCartagena Basin andsubsidence of the adjacent Fortuna Basin indicate thattectonic activity on the Alhama de Murcia Fault wasresponsible for the emergence of a threshold thatfinally led to deposition of the Tortonian evaporites inthe Fortuna basin

The question of the water exchanges between thethree major water reservoirs during the Messinian iethe global ocean the Mediterranean and the Paratethysis central for understanding the succession of paleoen-vironmental changes that affected the Mediterraneanduring the Messinian from the closure to the evaporiticconditions and then to the final dilution This point isaddressed by two papers respectively by Flecker andEllam from a hydrological budget modelling and byCcedilagatay et al from field studies in the Marmara region

The paper by Flecker and Ellam presents theresults of a study using 87Sr 86Sr data combinedwith an hydrologic budget modelling to determinethe nature and timing of the hydrological changes inthe restricted Mediterranean and of the connectionswith the open basins Three main events ie the pre-evaporitic restriction the initiation of salt precipitationand the connection between the Paratethys and theMediterranean through the Sea of Marmara are morespecifically investigated Among other results thestudy suggests the AtlanticndashMediterranean exchangewould have been reduced three million years beforethe onset of evaporite precipitation and the evaporiteformation triggered by an increase in the proportionof ocean water entering the Mediterranean rather thanby the closure of the connections Regarding thequestion of the ParatethysndashMediterranean connectionsthrough the Sea of Marmara the authors concludethat there are no evidences of increased inflow fromeither the Mediterranean and the Paratethys in thisarea

Ccedilagatay et al explore the problem of the waterexchanges between the Mediterranean and the Para-tethys realms through the Marmara region considered asa gateway since the Middle Miocene The work isfocused on the description of sedimentary successions inthe northeastern Aegean and northwestern Marmararegions where the Messinian (Alccedilyacutetepe Formation) wasdeposited predominantly in shallow brackish- to fresh-water conditions By a study of the faunal contentpaleomagnetic analyses and Sr isotope it is shown thatmarine incursions occurred frequently during theTortonian and the Messinian in the northeastern Aegeanregion but exchanges between the Sea of Marmararegion and the global ocean remained restricted through-out this period except for a connection at the base of theAlccedilitepe Fm Shallow marine conditions reappearedafter an erosional event during the Zanclean but noconnection via Marmara between Paratethys and theMediterranean was re-established until the Late Plio-cene This emphasizes the role of the tectonic activity ofthe North Anatolian Fault and global sea level rise

3Editorial

for an external invited paper (Lu and Meyers) In factthis issue gathers the papers which are mostly focusedon the geological aspects of the crisis while a secondspecial issue published by Geobios will be morespecifically devoted to paleobiological aspects

2 Summary of contents

Altogether these papers present a good overview ofthe current state of knowledge of the Messinian SalinityCrisis in its different aspects including the geodynamicalcontext new interpretative scenarios regional studiesand their global impact the deep marine record thequestion of the Lago-Mare the MediterraneanndashPara-tethys exchanges and the modelling

The opening paper of the volume by Jolivet et al ismainly concernedwith a review of the role of the tectonicfactors that are of crucial importance as they caused theisolation and shaped the size and morphology of thereceptacle for evaporite deposition as well as themodification of the basin paleogeography through theMessinian In the recent years several papers proposedto interpret the closure as the consequence of deep crustalprocesses These different aspects are discussed in thispaper that emplaces the Messinian Salinity Crisis withinthe tectonic and paleogeographic evolution of theMediterranean region from the Oligocene to the PresentThe isolation of the Mediterranean resulted from aprogressive process that started some 30ndash35 Myr agoFor the authors it took place after the end of the late-orogenic extension in the Alboran domain and at theonset of a new stage of NndashS compression and was notrelated to the slab retreat that would have rather delayedthe onset of the MSC

The second paper byRouchy and Caruso is mostly areview paper that provides an updated re-examination ofthe most salient features of the MSC and hydrologicalrequirements for evaporite deposition in order to assessthe viability of the new models and to built an integratedscenario The proposed scenario is in good agreementwith the key-points of the previous models but with newstatements about the chronology depositional settingshydrological mechanisms consequences and correla-tions with the global changes Here the two main stagesof evaporite deposition affected successively the wholebasin with a slight diachronism between shallow anddeep areas The isolation has been controlled predom-inantly by tectonic processes but changes of the worldsea level and regional climate interfered to explain thecomplex development of the evaporitic crisis Severalepisodes of enhanced erosion coeval with the majorevaporitic steps are merged on the margins to form a

major erosional surface and the crisis The crisis endedby a general dilution at the Mediterranean scale beforethe sharp restoration of the marine conditions in theearliest Zanclean

Two papers deal with the seismic record of the evap-orites along the offshore margins of the deep basins atthe transition with the deep evaporites respectively inthe Gulf of Valencia and on the eastern side of the Levantbasin

In the Valencia Basin Maillard et al describe indetail the relations between the evaporites the erosionalsurfaces and related clastic deposits and propose acorrelation between erosions sea level variations andevaporite deposition The authors provide evidence oftwo major erosional surfaces which are bracketing theevaporite succession respectively at its base and top andmerge marginward in a single surface The basal surfaceextends into the Central Valencia Basin and the detritalproducts produced by the erosion grade laterally into themassive salt of the deep Provenccedilal Basin indicating thatan important sea-level fall occurred as soon as thebeginning of the Messinian Salinity Crisis Theoverlying Upper Evaporites unit display a transgressivepattern towards the margins where they onlap the basalsurface They are truncated at the top by a network ofincisions interpreted as a final erosional episode linkedto the Lago-Mare event

From the study of a series of 2D and 3D seismiclines Bertoni and Cartwright provide a characteriza-tion and mapping of the evaporites in the southeasternpart of the Levant margin and show their distributionand architecture are mostly constrained by structural anderosional features A series of structural highs related toanticlines of the Syrian Arc foldbelt formed a barrier thatcontrolled the overall landward extension of theevaporites Submarine canyons (Afiq El Arish andAshdod Canyons) which were active at least since theOligocene represented preferential sites of erosion andevaporite deposition explaining the irregular geometryof the edge of the evaporites characterized by majorembayments and landward outliers

The next group of three papers are field-based studiesin the Betic basins which have important implications ata regional scale as the first two papers by Lu and Meyersand Braga et al lead to the proposition of differentinterpretative scenarios and the third paper by Krijgsmanet al addresses the controversial question of whether theevaporite deposition was controlled by eustatic sea-levelchanges or by tectonics

From the analysis of the depositional facies andfabrics of the Messinian gypsum and associated depositsin the Nijar basin Lu and Meyers reconstruct the

4 Editorial

evolution of the depositional paleodepths throughout theevaporitic event The gypsum deposited continuously insubaqueous conditions with water depth commonly near10ndash30 m and occasionally up to 100 m or deeperAlthough two major drops with a magnitude of sim140 moccurred before and after the deposition of Yesaresevaporites the basin never desiccated Depth fluctua-tions around 50ndash80 m of magnitude which occurred inrelation with the deposition of alternating gypsum andmarls are thought to be the result of glacio-eustaticfluctuations These data lead the authors to suggest ascenario for the Messinian event in which the evaporitesformed in two steps that affected successively the wholeMediterranean but in which the evaporites formed inldquodeeprdquo water conditions rather than during the desicca-tion of the basin

By the study of the sedimentary record in the SorbasAlmeriacutea-Niacutejar and Vera basins Braga et al provide newarguments for the model they proposed about 10 yearsago (Riding et al 1998) In this model these basinsremained connected with the Mediterranean throughoutthe Messinian except during a major desiccation phaserelated to salt deposition in the deep basin of theWesternMediterranean that occurred abruptly at the beginning ofthe crisis The sea level fall caused the erosion of the pre-evaporitic marine deposits (Yesares Member) and wasfollowed during the late Messinian by the restoration ofsea-levels as high as those that preceded the desiccationThe deposition of the gypsum of the Betic basins post-dates the salt formation and formed in marginal silled-basins during the marine reflooding prior to theMessinianndashZanclean boundary In this scenario the sig-nificance of the Lago-Mare facies is restricted to verylocalized continental settings adjacent to the Mediterra-nean Sea

In their paper Krijgsman et al investigate whichof the tectonic uplift or sea level lowering wasresponsible for the deposition of the Tortonianevaporites of the Eastern Betics Using a multidisci-plinary approach combining biostratigraphy magne-tostratigraphy and isotopic datings they obtain a highresolution chronology for the Venta de la Virgensection in the MurciandashCartagena Basin The resultsand the correlation with the Sorbas Basin demonstratethat the dominant factor was the local tectonic activitywhile eustatic sea-level changes had minor influenceCoeval uplift of the MurciandashCartagena Basin andsubsidence of the adjacent Fortuna Basin indicate thattectonic activity on the Alhama de Murcia Fault wasresponsible for the emergence of a threshold thatfinally led to deposition of the Tortonian evaporites inthe Fortuna basin

The question of the water exchanges between thethree major water reservoirs during the Messinian iethe global ocean the Mediterranean and the Paratethysis central for understanding the succession of paleoen-vironmental changes that affected the Mediterraneanduring the Messinian from the closure to the evaporiticconditions and then to the final dilution This point isaddressed by two papers respectively by Flecker andEllam from a hydrological budget modelling and byCcedilagatay et al from field studies in the Marmara region

The paper by Flecker and Ellam presents theresults of a study using 87Sr 86Sr data combinedwith an hydrologic budget modelling to determinethe nature and timing of the hydrological changes inthe restricted Mediterranean and of the connectionswith the open basins Three main events ie the pre-evaporitic restriction the initiation of salt precipitationand the connection between the Paratethys and theMediterranean through the Sea of Marmara are morespecifically investigated Among other results thestudy suggests the AtlanticndashMediterranean exchangewould have been reduced three million years beforethe onset of evaporite precipitation and the evaporiteformation triggered by an increase in the proportionof ocean water entering the Mediterranean rather thanby the closure of the connections Regarding thequestion of the ParatethysndashMediterranean connectionsthrough the Sea of Marmara the authors concludethat there are no evidences of increased inflow fromeither the Mediterranean and the Paratethys in thisarea

Ccedilagatay et al explore the problem of the waterexchanges between the Mediterranean and the Para-tethys realms through the Marmara region considered asa gateway since the Middle Miocene The work isfocused on the description of sedimentary successions inthe northeastern Aegean and northwestern Marmararegions where the Messinian (Alccedilyacutetepe Formation) wasdeposited predominantly in shallow brackish- to fresh-water conditions By a study of the faunal contentpaleomagnetic analyses and Sr isotope it is shown thatmarine incursions occurred frequently during theTortonian and the Messinian in the northeastern Aegeanregion but exchanges between the Sea of Marmararegion and the global ocean remained restricted through-out this period except for a connection at the base of theAlccedilitepe Fm Shallow marine conditions reappearedafter an erosional event during the Zanclean but noconnection via Marmara between Paratethys and theMediterranean was re-established until the Late Plio-cene This emphasizes the role of the tectonic activity ofthe North Anatolian Fault and global sea level rise

4 Editorial

evolution of the depositional paleodepths throughout theevaporitic event The gypsum deposited continuously insubaqueous conditions with water depth commonly near10ndash30 m and occasionally up to 100 m or deeperAlthough two major drops with a magnitude of sim140 moccurred before and after the deposition of Yesaresevaporites the basin never desiccated Depth fluctua-tions around 50ndash80 m of magnitude which occurred inrelation with the deposition of alternating gypsum andmarls are thought to be the result of glacio-eustaticfluctuations These data lead the authors to suggest ascenario for the Messinian event in which the evaporitesformed in two steps that affected successively the wholeMediterranean but in which the evaporites formed inldquodeeprdquo water conditions rather than during the desicca-tion of the basin

By the study of the sedimentary record in the SorbasAlmeriacutea-Niacutejar and Vera basins Braga et al provide newarguments for the model they proposed about 10 yearsago (Riding et al 1998) In this model these basinsremained connected with the Mediterranean throughoutthe Messinian except during a major desiccation phaserelated to salt deposition in the deep basin of theWesternMediterranean that occurred abruptly at the beginning ofthe crisis The sea level fall caused the erosion of the pre-evaporitic marine deposits (Yesares Member) and wasfollowed during the late Messinian by the restoration ofsea-levels as high as those that preceded the desiccationThe deposition of the gypsum of the Betic basins post-dates the salt formation and formed in marginal silled-basins during the marine reflooding prior to theMessinianndashZanclean boundary In this scenario the sig-nificance of the Lago-Mare facies is restricted to verylocalized continental settings adjacent to the Mediterra-nean Sea

In their paper Krijgsman et al investigate whichof the tectonic uplift or sea level lowering wasresponsible for the deposition of the Tortonianevaporites of the Eastern Betics Using a multidisci-plinary approach combining biostratigraphy magne-tostratigraphy and isotopic datings they obtain a highresolution chronology for the Venta de la Virgensection in the MurciandashCartagena Basin The resultsand the correlation with the Sorbas Basin demonstratethat the dominant factor was the local tectonic activitywhile eustatic sea-level changes had minor influenceCoeval uplift of the MurciandashCartagena Basin andsubsidence of the adjacent Fortuna Basin indicate thattectonic activity on the Alhama de Murcia Fault wasresponsible for the emergence of a threshold thatfinally led to deposition of the Tortonian evaporites inthe Fortuna basin

The question of the water exchanges between thethree major water reservoirs during the Messinian iethe global ocean the Mediterranean and the Paratethysis central for understanding the succession of paleoen-vironmental changes that affected the Mediterraneanduring the Messinian from the closure to the evaporiticconditions and then to the final dilution This point isaddressed by two papers respectively by Flecker andEllam from a hydrological budget modelling and byCcedilagatay et al from field studies in the Marmara region

The paper by Flecker and Ellam presents theresults of a study using 87Sr 86Sr data combinedwith an hydrologic budget modelling to determinethe nature and timing of the hydrological changes inthe restricted Mediterranean and of the connectionswith the open basins Three main events ie the pre-evaporitic restriction the initiation of salt precipitationand the connection between the Paratethys and theMediterranean through the Sea of Marmara are morespecifically investigated Among other results thestudy suggests the AtlanticndashMediterranean exchangewould have been reduced three million years beforethe onset of evaporite precipitation and the evaporiteformation triggered by an increase in the proportionof ocean water entering the Mediterranean rather thanby the closure of the connections Regarding thequestion of the ParatethysndashMediterranean connectionsthrough the Sea of Marmara the authors concludethat there are no evidences of increased inflow fromeither the Mediterranean and the Paratethys in thisarea

Ccedilagatay et al explore the problem of the waterexchanges between the Mediterranean and the Para-tethys realms through the Marmara region considered asa gateway since the Middle Miocene The work isfocused on the description of sedimentary successions inthe northeastern Aegean and northwestern Marmararegions where the Messinian (Alccedilyacutetepe Formation) wasdeposited predominantly in shallow brackish- to fresh-water conditions By a study of the faunal contentpaleomagnetic analyses and Sr isotope it is shown thatmarine incursions occurred frequently during theTortonian and the Messinian in the northeastern Aegeanregion but exchanges between the Sea of Marmararegion and the global ocean remained restricted through-out this period except for a connection at the base of theAlccedilitepe Fm Shallow marine conditions reappearedafter an erosional event during the Zanclean but noconnection via Marmara between Paratethys and theMediterranean was re-established until the Late Plio-cene This emphasizes the role of the tectonic activity ofthe North Anatolian Fault and global sea level rise

5Editorial

The paper by Playagrave and Gimeno addresses thequestion of the relations evaporitesndashvolcanism which isa key to solve definitely the problem of the age of theevaporites in the marginal basins of southern Spain likethe Fortuna basin Did the volcanism occur coevallywith the evaporite sedimentation or later as suggested bythe intrusive character of the outcrops of lamproitic(fortunites) rocks The authors provide evidences ofmagmandashsediment interactions that produced peperiticrocks implying that the eruption was nearly coeval withthe deposition of the host water-rich sediments duringthe deposition of the latest evaporitic event (RamblaSalada Gypsum Unit) This opens the way for furtherdatation of these evaporitic deposits

Based on the study of the palynological record thepaper by Bertini reconstructs the vegetation and climatechanges that occurred in the Northern Apenninesthrough the period concerned by the salinity crisis Inthis area humid subtropical and warm conditionspredominated throughout the evaporitic and postevaporitic periods but was nevertheless marked byperiodical wetterdryer fluctuations and by a dryer phaseat about 55 Ma related to a global warming period It isinferred that at the Mediterranean scale the climate didnot undergo huge changes but was characterized byimportant gradients indicated by the persistence ofthermo-xeric conditions in the southern areas as inSicily The significance of the Lago-Mare in terms ofclimate and paleoenvironments is also discussed

The significance of the Lago-Mare deposits has longbeen a subject of controversy that increased during thetwo last decades as reflected in this volume by the twoopposed concepts developed by Rouchy and Carusowho consider it records a widespread dilution at the endof the Messinian and Braga et al for whom the Lago-Mare deposits are representative of very localizedsettings influenced by continental inputs at the peripheryof the Mediterranean Sea It occurred during a period ofmore efficient closure of the Mediterranean for the firstauthors or while the marine conditions were already re-established for the second ones This question is morespecifically addressed by three papers a review paperby F Orszag-Sperber and two regional studiesrespectively by Bassetti et al in Southern Spain andCosentino et al in western central Italy

As stressed by Orszag-Sperber the significance ofthe Lago-Mare event is closely related to the problem ofthe exchanges between the Mediterranean and theParatethys and of the presence in the Mediterraneanof faunal assemblages of Paratethyan affinities Theauthor proposes a documented review of the history ofthe Lago-Mare meaning that does not recover exactly

the same concepts according to the authors Does thisevent represent just a period of dilution at the end of theMessinian that would have favoured the adaptation ofParatethyan immigrants in a Mediterranean convertedinto brackish lakes Did free connections act at leastperiodically between the two realms to make possible anaquatic migration of this fauna By which ways wouldthese connections have transited Such are some of thequestions discussed in this paper that also presents aregional case study in Cyprus

After a description of the evaporitic succession of theNijar Basin the paper by Bassetti et al is focused onthe latest Messinian deposits which contain an assem-blage of non-marine aquatic communities of ostracodsliving in hypohaline conditions and representative of theLago-Mare fauna The ostracod fauna is similar to thatdocumented elsewhere in Spain France and Italystrengthening the hypothesis of a widespread dilutionevent at the regional scale For the authors the lownumber of species common to the Western Mediterra-nean and Parathetys indicates that the Lago-Mare faunais likely endemic at Mediterranean scale The majorityof the foraminifers found within the post-evaporiticsuccession are interpreted as being reworked in contrastwith the hypothesis that would consider the foraminiferassemblages of the same layers as indicators of a marinetransgression However a transitional interval with in-situ foraminifers seems to predate the main inundationin the basal Pliocene

In theMondragone 1 well drilled within the Gariglianoplain on the western margin of the Tyrrhenian basinCosentino et al describe a 940-m thick sedimentarysuccession of Lago-Mare deposits dominated by clasticsediments that can be correlated with the 530-m thickpre-Pliocene lacustrine deposits recovered at the ODPSite 652 in the Tyrrhenian abyssal plain The presence intheMondragone 1 well of an ostracod assemblage of theLoxocorniculina djafarovi Zone permits to ascribe thisinterval to the Lago-Mare event As indicated by thefaunal content (ostracods gastropods) the sedimenta-tion occurred in lacustrine settings with freshwater tooligo-mesohaline conditions The nannofossil assem-blages are reworked indicating that no marine episodeoccurred during this interval neither during theoverlying Pliocene The unusually large variations ofthickness recorded by the Lago-Mare deposits at theregional scale reflect active syn-sedimentary extensionaltectonics during a syn-rift stage

The following two articles deal with the environ-mental change that occurred at the MiocenendashPlioceneboundary which is characterized by the rapid restorationof the marine conditions and are focused on the

6 Editorial

characterisation of the depositional environments forone (Pierre et al) and on the process that caused theopening of the Gibraltar strait for the second

Pierre et al investigated the latest Messinianndashearliest Zanclean transition using a combined micro-paleontological mineralogical and stable isotope studiesperformed on a high sampling resolution of fieldsections and ODP cores located along a WndashE transectfrom Spain to Cyprus In agreement with previous stu-dies it is shown that the latest Messinian sedimentsdeposited in continentalbrackish environments typicalof the Lago-Mare event both in marginal and deepbasins while the earliest Pliocene sediments were de-posited in open marine settings The restoration ofmarine conditions corresponds to a very rapid althoughprogressive change that occurred more or less contem-poraneously through a brief transitional interval withinthe whole Mediterranean Stabilisation of normal marineconditions was established definitely around 20 kyr afterthe re-establishment of connections between the Med-iterranean and the Atlantic

Loget and Van Den Driessche explore the role ofthe subaerial erosion for the re-opening of the AtlanticndashMediterranean connections at the beginning of thePliocene It starts with a documented discussion of thearguments proposed in the literature in favour of atectonically-controlled process or of an Atlantic sea-level rise showing they are no convincing proof forneither of them By a review of the geological observa-tions and the use of a numerical modelling they proposethat the reflooding of the Mediterranean was due to theregressive erosion of a stream flowing on the edge of theGibraltar barrier into the desiccated Mediterranean Thisultimately caused the breakdown of the barrier leadingto the opening of the Gibraltar strait and the capture ofthe Atlantic waters

From a detailed description of the karst and cavesystems developed along the Ardegraveche River atributary of the Rhocircne River in southern FranceMocochain et al interpret the karst responses to theeustatic changes that affected the Mediterraneanduring Messinian and Pliocene times The chronologyand dynamics of the karst formation are established bycorrelation with the benchmark levels showing twodistinct steps The huge fall in base-level during thesalinity crisis caused first the incision of canyons andthe development of deep karst systems These karstswere subsequently drowned and plugged by sedimentsduring the early Zanclean reflooding that resulted inthe backward flow of the groundwater through thekarst system to generate ldquochimney-shaftsrdquo in Vauclu-sian karst systems

The Messinian evaporites have had a profound effectupon the geodynamic evolution of the eastern Mediter-ranean for the building of the accretionary prism of theMediterranean Ridge and the formation of deep brinefilled basins In a documented review paper Citasynthesizes the data which have been collected on fiveof these brine pools (Tyro Bannock Uania Atalanteand Discovery) which were discovered between 1983and 1994 in the Mediterranean Ridge Geochemicalhydrological and geological characteristics of thesebrines basins are provided and discussed and theirformation interpreted as the result of the submarinedissolution of Messinian evaporites exhumed on the seafloor in different structural settings The very highconcentration of the Discovery brines that are saturatedfor the bischofite a Mg chloride mineral that requiresnearly complete evaporation of sea water to precipitatesuggests that at the end of the Messinian the deepestareas of the Eastern Mediterranean were close to dry-ness in agreement with the model of deep sea desic-cated basin

The final paper in the volume by Peryt describes theBadenian (Middle Miocene equivalent to LanghianndashSerravalian pro-parte) evaporites of the Carpathianregion that provides another example of a Neogenesalinity crisis displaying great similarities and differ-ences with the Messinian event of the Mediterranean Asfor the Messinian the evaporites are underlain andoverlain by deep-water deposits Isolation from theTethys resulted from an eustatic sea-level fall coupledwith tectonic processes Evaporite deposition startedsuddenly but diachroneously in the basin centre beforeto shift marginward accompanying the migration of thesedimentary areas induced by the nappe movementAlthough differences at the regional scale the end of thecrisis resulted from a global sea level rise that caused thequick reflooding of the evaporitic basins and thetransition to marine sedimentation

3 Conclusions

The papers presented in this issue illustrate theconsiderable progress obtained in the knowledge of thevarious aspects of the Messinian Salinity Crisis butalso the great diversity of the ideas and even the strongdisagreement that persists for the interpretation ofmany of these aspects Rather than to be disappointedby such a diversity we must consider it as a source ofemulation for future researches and progress in theunderstanding of this unusual event One of thegreatest challenges for future work and one of theclue for the final interpretation would be to obtain a

7Editorial

precise record of the Messinian event in the deepestareas of the Mediterranean in terms of chronology anddepositional environments We must not forget thatmost of 90 of the evaporite deposits are located inthese areas and still inaccessible to direct observationAt this time we have not any data neither on the onsetof the crisis in these areas (including its exact timing)nor on depositional environment in which the thick andmassive salt deposits formed The project of drillingthe whole evaporitic sequence in one of the deepestparts of the Mediterranean basins during a future IODPproject represents the only possibility to get nearer tothe truth A session of the Corte Colloquium has beendedicated to this project that received a large interestfrom the scientific community present in the meetingThis is a very exciting challenge and we hope it willopen a new intellectual adventure as rich as the pre-ceding one

Acknowledgements

We want to thank Elsevier Science and the Chief-editors and technical staff of Sedimentary Geology forthe opportunity offered by this Special issue Webenefited throughout the preparation of this volume ofthe constant guidance and encouragements of Mr TonnySmit Publishing Support Manager and Mrs Tirza vanDaalen Publishing Editor and their collaborators

As editors we are very indebted to the referees thatspent time and effort to ensure the best quality of themanuscripts M Bakalowicz (Montpellier France) MA Bassetti (Brest France) A Bini (Milan Italy) ACherchi (Cagliari Italy) MB Cita (Milan Italy) JDeverchegravere (Brest France) AF Fortuin (AmsterdamThe Netherlands) A Garlicki (Cracovia Poland) LJolivet (Paris France) S Iaccarino (Parma Italy) WKrijgsman (Utrecht The Netherlands) A Longinelli(Parma Italy) H Lu (Shaw USA) S Lugli (ModenaItaly) J Mascle (Villefranche-sur-Mer France) FOrszag-Sperber (Paris-Orsay France) O Ohms (Bar-celona Spain) F Ortiacute (Barcelona Spain) M Pedley(Hull Great Britain) E Patacca (Pisa Italy) VPascucci (Sassari Italy) S Popov (Moscow Russia)J-C Plaziat (Paris-Orsay France) J-P Rehault(Brest France) BC Schreiber (New York USA)M Steckler (New York USA) F Steininger (Frank-furt-on-Main Germany) A Stefanon (Venice Italy)GB Vai (Bologna Italy) JK Warren (Brunei) RWortel (Utrecht The Netherlands) and five reviewersthat preferred to remain anonymous We want to thankall authors for their efforts to complete the revisionprocess in the short deadlines that were fixed allowing

us to keep the project in the schedule initiallyproposed during the Corte meeting

The Corte meeting was possible thanks to thefinancial support of the University Pascal Paoli(Corsica) to the French CNRS ECLIPSE Programmeand to the ESF EEDEN Programme

The help of MM Blanc-Valleron and A Cambre-leng from the Museacuteum national Histoire naturelle hasbeen very appreciated

References

Benson RH (Ed) 1976 The biodynamic effects of the Messiniansalinity crisis Palaeogeogr Palaeoclimatol Palaeoecol vol 20170 pp

Benson RH Rakic-el Bied K 1991 Biodynamics saline giants andlate Miocene catastrophism Carbonates and Evaporites 6127ndash168

Benson RH Hayek LAC Hodell DA Rakic-el-Bied K 1995Extending the climatic precession curve back into the late Mioceneby signature template correlation Paleoceanography 10 5ndash20

Blanc P-L 2002 The opening of the PliondashQuaternary GibraltarStrait assessing the size of a cataclysm Geodin Acta 15 117ndash122

Butler RWH Lickorish WH Grasso M Pedley HM RambertiL 1995 Tectonics and sequence stratigraphy in Messinian basinsSicily constraints on the initiation and termination of the Mediter-ranean salinity crisis Geol Soc Amer Bull 107 425ndash439

Catalano R Ruggieri G Sprovieri R (Eds) 1978 Messinian evap-orites in the Mediterranean Mem Soc Geol Ital vol 16 385 pp

Cita MB Ryan WBF (Eds) 1978 Messinian erosional surfaces inthe Mediterranean Mar Geol vol 27 366 pp

Cita MB Wright RC (Eds) 197980 Geodynamic and biody-namic effects of the Messinian salinity crisis in the MediterraneanPalaeogeogr Palaeoclimatol Palaeoecol vol 29 222 pp

Cita MB Wright RC Ryan WBF Longinelli A 1978Messinian paleoenvironments In Hsuuml KJ Montadert L et al(Eds) Initial Reports of the Deep Sea Drilling Project vol 42 (I)US Government Printing Office Washington pp 1003ndash1035

Clauzon G Suc J-P Gautier F Berger A Loutre M-F 1996Alternate interpretation of the Messinian salinity crisis controver-sy resolved Geology 24 363ndash366

Clauzon G Suc J-P Popescu S-M Marunteanu M RubinoJ-L Marinescu F Melinte MC 2005 Influence of theMediterranean sea-level changes over the Dacic Basin (EasternParatethys) in the Late Neogene The Mediterranean Lago Marefacies deciphered Basin Research 17 437ndash462

Drooger CW (Ed) 1973 Messinian events in the MediterraneanKon Ned Akad VanWetensch Geodyn Scient Rep ndeg7 272 pp

Gautier F Clauzon G Suc J-P Cravatte J Violanti D 1994Age et dureacutee de la crise de saliniteacute Messinienne CR Acad SciParis 318 1103ndash1109

Hardie AH Lowenstein TK 2004 Did the Mediterranean Sea dryout during the Miocene A reassessment of the evaporite evidencefrom DSDP Leg 13 and 42A cores J Sediment Res 74 453ndash461

Hilgen FJ Krijgsman W 1999 Cyclostratigraphy and astrochro-nology of the Tripoli diatomite formation (pre-evaporite MessinianSicily Italy) Terra Nova 11 16ndash22

Hilgen FJ Krijgsman W Langereis CG Lourens LJ SantarelliA Zachariasse WJ 1995 Extending the astronomical (polarity)time scale into the Miocene Earth Planet Sci Lett 136 495ndash510

6 Editorial

characterisation of the depositional environments forone (Pierre et al) and on the process that caused theopening of the Gibraltar strait for the second

Pierre et al investigated the latest Messinianndashearliest Zanclean transition using a combined micro-paleontological mineralogical and stable isotope studiesperformed on a high sampling resolution of fieldsections and ODP cores located along a WndashE transectfrom Spain to Cyprus In agreement with previous stu-dies it is shown that the latest Messinian sedimentsdeposited in continentalbrackish environments typicalof the Lago-Mare event both in marginal and deepbasins while the earliest Pliocene sediments were de-posited in open marine settings The restoration ofmarine conditions corresponds to a very rapid althoughprogressive change that occurred more or less contem-poraneously through a brief transitional interval withinthe whole Mediterranean Stabilisation of normal marineconditions was established definitely around 20 kyr afterthe re-establishment of connections between the Med-iterranean and the Atlantic

Loget and Van Den Driessche explore the role ofthe subaerial erosion for the re-opening of the AtlanticndashMediterranean connections at the beginning of thePliocene It starts with a documented discussion of thearguments proposed in the literature in favour of atectonically-controlled process or of an Atlantic sea-level rise showing they are no convincing proof forneither of them By a review of the geological observa-tions and the use of a numerical modelling they proposethat the reflooding of the Mediterranean was due to theregressive erosion of a stream flowing on the edge of theGibraltar barrier into the desiccated Mediterranean Thisultimately caused the breakdown of the barrier leadingto the opening of the Gibraltar strait and the capture ofthe Atlantic waters

From a detailed description of the karst and cavesystems developed along the Ardegraveche River atributary of the Rhocircne River in southern FranceMocochain et al interpret the karst responses to theeustatic changes that affected the Mediterraneanduring Messinian and Pliocene times The chronologyand dynamics of the karst formation are established bycorrelation with the benchmark levels showing twodistinct steps The huge fall in base-level during thesalinity crisis caused first the incision of canyons andthe development of deep karst systems These karstswere subsequently drowned and plugged by sedimentsduring the early Zanclean reflooding that resulted inthe backward flow of the groundwater through thekarst system to generate ldquochimney-shaftsrdquo in Vauclu-sian karst systems

The Messinian evaporites have had a profound effectupon the geodynamic evolution of the eastern Mediter-ranean for the building of the accretionary prism of theMediterranean Ridge and the formation of deep brinefilled basins In a documented review paper Citasynthesizes the data which have been collected on fiveof these brine pools (Tyro Bannock Uania Atalanteand Discovery) which were discovered between 1983and 1994 in the Mediterranean Ridge Geochemicalhydrological and geological characteristics of thesebrines basins are provided and discussed and theirformation interpreted as the result of the submarinedissolution of Messinian evaporites exhumed on the seafloor in different structural settings The very highconcentration of the Discovery brines that are saturatedfor the bischofite a Mg chloride mineral that requiresnearly complete evaporation of sea water to precipitatesuggests that at the end of the Messinian the deepestareas of the Eastern Mediterranean were close to dry-ness in agreement with the model of deep sea desic-cated basin

The final paper in the volume by Peryt describes theBadenian (Middle Miocene equivalent to LanghianndashSerravalian pro-parte) evaporites of the Carpathianregion that provides another example of a Neogenesalinity crisis displaying great similarities and differ-ences with the Messinian event of the Mediterranean Asfor the Messinian the evaporites are underlain andoverlain by deep-water deposits Isolation from theTethys resulted from an eustatic sea-level fall coupledwith tectonic processes Evaporite deposition startedsuddenly but diachroneously in the basin centre beforeto shift marginward accompanying the migration of thesedimentary areas induced by the nappe movementAlthough differences at the regional scale the end of thecrisis resulted from a global sea level rise that caused thequick reflooding of the evaporitic basins and thetransition to marine sedimentation

3 Conclusions

The papers presented in this issue illustrate theconsiderable progress obtained in the knowledge of thevarious aspects of the Messinian Salinity Crisis butalso the great diversity of the ideas and even the strongdisagreement that persists for the interpretation ofmany of these aspects Rather than to be disappointedby such a diversity we must consider it as a source ofemulation for future researches and progress in theunderstanding of this unusual event One of thegreatest challenges for future work and one of theclue for the final interpretation would be to obtain a

7Editorial

precise record of the Messinian event in the deepestareas of the Mediterranean in terms of chronology anddepositional environments We must not forget thatmost of 90 of the evaporite deposits are located inthese areas and still inaccessible to direct observationAt this time we have not any data neither on the onsetof the crisis in these areas (including its exact timing)nor on depositional environment in which the thick andmassive salt deposits formed The project of drillingthe whole evaporitic sequence in one of the deepestparts of the Mediterranean basins during a future IODPproject represents the only possibility to get nearer tothe truth A session of the Corte Colloquium has beendedicated to this project that received a large interestfrom the scientific community present in the meetingThis is a very exciting challenge and we hope it willopen a new intellectual adventure as rich as the pre-ceding one

Acknowledgements

We want to thank Elsevier Science and the Chief-editors and technical staff of Sedimentary Geology forthe opportunity offered by this Special issue Webenefited throughout the preparation of this volume ofthe constant guidance and encouragements of Mr TonnySmit Publishing Support Manager and Mrs Tirza vanDaalen Publishing Editor and their collaborators

As editors we are very indebted to the referees thatspent time and effort to ensure the best quality of themanuscripts M Bakalowicz (Montpellier France) MA Bassetti (Brest France) A Bini (Milan Italy) ACherchi (Cagliari Italy) MB Cita (Milan Italy) JDeverchegravere (Brest France) AF Fortuin (AmsterdamThe Netherlands) A Garlicki (Cracovia Poland) LJolivet (Paris France) S Iaccarino (Parma Italy) WKrijgsman (Utrecht The Netherlands) A Longinelli(Parma Italy) H Lu (Shaw USA) S Lugli (ModenaItaly) J Mascle (Villefranche-sur-Mer France) FOrszag-Sperber (Paris-Orsay France) O Ohms (Bar-celona Spain) F Ortiacute (Barcelona Spain) M Pedley(Hull Great Britain) E Patacca (Pisa Italy) VPascucci (Sassari Italy) S Popov (Moscow Russia)J-C Plaziat (Paris-Orsay France) J-P Rehault(Brest France) BC Schreiber (New York USA)M Steckler (New York USA) F Steininger (Frank-furt-on-Main Germany) A Stefanon (Venice Italy)GB Vai (Bologna Italy) JK Warren (Brunei) RWortel (Utrecht The Netherlands) and five reviewersthat preferred to remain anonymous We want to thankall authors for their efforts to complete the revisionprocess in the short deadlines that were fixed allowing

us to keep the project in the schedule initiallyproposed during the Corte meeting

The Corte meeting was possible thanks to thefinancial support of the University Pascal Paoli(Corsica) to the French CNRS ECLIPSE Programmeand to the ESF EEDEN Programme

The help of MM Blanc-Valleron and A Cambre-leng from the Museacuteum national Histoire naturelle hasbeen very appreciated

References

Benson RH (Ed) 1976 The biodynamic effects of the Messiniansalinity crisis Palaeogeogr Palaeoclimatol Palaeoecol vol 20170 pp

Benson RH Rakic-el Bied K 1991 Biodynamics saline giants andlate Miocene catastrophism Carbonates and Evaporites 6127ndash168

Benson RH Hayek LAC Hodell DA Rakic-el-Bied K 1995Extending the climatic precession curve back into the late Mioceneby signature template correlation Paleoceanography 10 5ndash20

Blanc P-L 2002 The opening of the PliondashQuaternary GibraltarStrait assessing the size of a cataclysm Geodin Acta 15 117ndash122

Butler RWH Lickorish WH Grasso M Pedley HM RambertiL 1995 Tectonics and sequence stratigraphy in Messinian basinsSicily constraints on the initiation and termination of the Mediter-ranean salinity crisis Geol Soc Amer Bull 107 425ndash439

Catalano R Ruggieri G Sprovieri R (Eds) 1978 Messinian evap-orites in the Mediterranean Mem Soc Geol Ital vol 16 385 pp

Cita MB Ryan WBF (Eds) 1978 Messinian erosional surfaces inthe Mediterranean Mar Geol vol 27 366 pp

Cita MB Wright RC (Eds) 197980 Geodynamic and biody-namic effects of the Messinian salinity crisis in the MediterraneanPalaeogeogr Palaeoclimatol Palaeoecol vol 29 222 pp

Cita MB Wright RC Ryan WBF Longinelli A 1978Messinian paleoenvironments In Hsuuml KJ Montadert L et al(Eds) Initial Reports of the Deep Sea Drilling Project vol 42 (I)US Government Printing Office Washington pp 1003ndash1035

Clauzon G Suc J-P Gautier F Berger A Loutre M-F 1996Alternate interpretation of the Messinian salinity crisis controver-sy resolved Geology 24 363ndash366

Clauzon G Suc J-P Popescu S-M Marunteanu M RubinoJ-L Marinescu F Melinte MC 2005 Influence of theMediterranean sea-level changes over the Dacic Basin (EasternParatethys) in the Late Neogene The Mediterranean Lago Marefacies deciphered Basin Research 17 437ndash462

Drooger CW (Ed) 1973 Messinian events in the MediterraneanKon Ned Akad VanWetensch Geodyn Scient Rep ndeg7 272 pp

Gautier F Clauzon G Suc J-P Cravatte J Violanti D 1994Age et dureacutee de la crise de saliniteacute Messinienne CR Acad SciParis 318 1103ndash1109

Hardie AH Lowenstein TK 2004 Did the Mediterranean Sea dryout during the Miocene A reassessment of the evaporite evidencefrom DSDP Leg 13 and 42A cores J Sediment Res 74 453ndash461

Hilgen FJ Krijgsman W 1999 Cyclostratigraphy and astrochro-nology of the Tripoli diatomite formation (pre-evaporite MessinianSicily Italy) Terra Nova 11 16ndash22

Hilgen FJ Krijgsman W Langereis CG Lourens LJ SantarelliA Zachariasse WJ 1995 Extending the astronomical (polarity)time scale into the Miocene Earth Planet Sci Lett 136 495ndash510

7Editorial

precise record of the Messinian event in the deepestareas of the Mediterranean in terms of chronology anddepositional environments We must not forget thatmost of 90 of the evaporite deposits are located inthese areas and still inaccessible to direct observationAt this time we have not any data neither on the onsetof the crisis in these areas (including its exact timing)nor on depositional environment in which the thick andmassive salt deposits formed The project of drillingthe whole evaporitic sequence in one of the deepestparts of the Mediterranean basins during a future IODPproject represents the only possibility to get nearer tothe truth A session of the Corte Colloquium has beendedicated to this project that received a large interestfrom the scientific community present in the meetingThis is a very exciting challenge and we hope it willopen a new intellectual adventure as rich as the pre-ceding one

Acknowledgements

We want to thank Elsevier Science and the Chief-editors and technical staff of Sedimentary Geology forthe opportunity offered by this Special issue Webenefited throughout the preparation of this volume ofthe constant guidance and encouragements of Mr TonnySmit Publishing Support Manager and Mrs Tirza vanDaalen Publishing Editor and their collaborators

As editors we are very indebted to the referees thatspent time and effort to ensure the best quality of themanuscripts M Bakalowicz (Montpellier France) MA Bassetti (Brest France) A Bini (Milan Italy) ACherchi (Cagliari Italy) MB Cita (Milan Italy) JDeverchegravere (Brest France) AF Fortuin (AmsterdamThe Netherlands) A Garlicki (Cracovia Poland) LJolivet (Paris France) S Iaccarino (Parma Italy) WKrijgsman (Utrecht The Netherlands) A Longinelli(Parma Italy) H Lu (Shaw USA) S Lugli (ModenaItaly) J Mascle (Villefranche-sur-Mer France) FOrszag-Sperber (Paris-Orsay France) O Ohms (Bar-celona Spain) F Ortiacute (Barcelona Spain) M Pedley(Hull Great Britain) E Patacca (Pisa Italy) VPascucci (Sassari Italy) S Popov (Moscow Russia)J-C Plaziat (Paris-Orsay France) J-P Rehault(Brest France) BC Schreiber (New York USA)M Steckler (New York USA) F Steininger (Frank-furt-on-Main Germany) A Stefanon (Venice Italy)GB Vai (Bologna Italy) JK Warren (Brunei) RWortel (Utrecht The Netherlands) and five reviewersthat preferred to remain anonymous We want to thankall authors for their efforts to complete the revisionprocess in the short deadlines that were fixed allowing

us to keep the project in the schedule initiallyproposed during the Corte meeting

The Corte meeting was possible thanks to thefinancial support of the University Pascal Paoli(Corsica) to the French CNRS ECLIPSE Programmeand to the ESF EEDEN Programme

The help of MM Blanc-Valleron and A Cambre-leng from the Museacuteum national Histoire naturelle hasbeen very appreciated

References

Benson RH (Ed) 1976 The biodynamic effects of the Messiniansalinity crisis Palaeogeogr Palaeoclimatol Palaeoecol vol 20170 pp

Benson RH Rakic-el Bied K 1991 Biodynamics saline giants andlate Miocene catastrophism Carbonates and Evaporites 6127ndash168

Benson RH Hayek LAC Hodell DA Rakic-el-Bied K 1995Extending the climatic precession curve back into the late Mioceneby signature template correlation Paleoceanography 10 5ndash20

Blanc P-L 2002 The opening of the PliondashQuaternary GibraltarStrait assessing the size of a cataclysm Geodin Acta 15 117ndash122

Butler RWH Lickorish WH Grasso M Pedley HM RambertiL 1995 Tectonics and sequence stratigraphy in Messinian basinsSicily constraints on the initiation and termination of the Mediter-ranean salinity crisis Geol Soc Amer Bull 107 425ndash439

Catalano R Ruggieri G Sprovieri R (Eds) 1978 Messinian evap-orites in the Mediterranean Mem Soc Geol Ital vol 16 385 pp

Cita MB Ryan WBF (Eds) 1978 Messinian erosional surfaces inthe Mediterranean Mar Geol vol 27 366 pp

Cita MB Wright RC (Eds) 197980 Geodynamic and biody-namic effects of the Messinian salinity crisis in the MediterraneanPalaeogeogr Palaeoclimatol Palaeoecol vol 29 222 pp

Cita MB Wright RC Ryan WBF Longinelli A 1978Messinian paleoenvironments In Hsuuml KJ Montadert L et al(Eds) Initial Reports of the Deep Sea Drilling Project vol 42 (I)US Government Printing Office Washington pp 1003ndash1035

Clauzon G Suc J-P Gautier F Berger A Loutre M-F 1996Alternate interpretation of the Messinian salinity crisis controver-sy resolved Geology 24 363ndash366

Clauzon G Suc J-P Popescu S-M Marunteanu M RubinoJ-L Marinescu F Melinte MC 2005 Influence of theMediterranean sea-level changes over the Dacic Basin (EasternParatethys) in the Late Neogene The Mediterranean Lago Marefacies deciphered Basin Research 17 437ndash462

Drooger CW (Ed) 1973 Messinian events in the MediterraneanKon Ned Akad VanWetensch Geodyn Scient Rep ndeg7 272 pp

Gautier F Clauzon G Suc J-P Cravatte J Violanti D 1994Age et dureacutee de la crise de saliniteacute Messinienne CR Acad SciParis 318 1103ndash1109

Hardie AH Lowenstein TK 2004 Did the Mediterranean Sea dryout during the Miocene A reassessment of the evaporite evidencefrom DSDP Leg 13 and 42A cores J Sediment Res 74 453ndash461

Hilgen FJ Krijgsman W 1999 Cyclostratigraphy and astrochro-nology of the Tripoli diatomite formation (pre-evaporite MessinianSicily Italy) Terra Nova 11 16ndash22

Hilgen FJ Krijgsman W Langereis CG Lourens LJ SantarelliA Zachariasse WJ 1995 Extending the astronomical (polarity)time scale into the Miocene Earth Planet Sci Lett 136 495ndash510

Corresponding author

8 Editorial

Hodell DA Curtis JH Sierro FJ RaymoME 2001 Correlationof late Miocene to early Pliocene sequences between theMediterranean andNorthAtlantic Paleoceanography 16 164ndash178

Hsuuml KJ Cita MB Ryan WBF 1973 The origin of theMediterranean evaporites In Ryan WBF Hsuuml KJ et al(Eds) Init Repts DSDP vol 13 US Govt Printing OfficeWashington pp 1203ndash1231

Hsuuml KJ Montadert L et al 1978a In Rep Deep Sea Drill Projvol 42 US Government Printing Office Washington part I

Hsuuml KJ Montadert L Bernouilli D Cita MB Erikson AGarrison RG Kidd RB Meacuteliegraveres F Muumlller C Wright R1978b History of the Mediterranean salinity crisis In Hsuuml KJMontadert L et al (Eds) In Rep Deep Sea Drill Proj vol 42AUS Government Printing Washington DC pp 1053ndash1078

Kastens KA Mascle J et al (Eds) 1990 Proc ODP Sci Resultsvol 107 Ocean Drilling Program College Station TX

Krijgsman W Hilgen FJ Langereis CG Santarelli A Zachar-iasse WJ 1995 Late Miocene magnetostratigraphy biostratig-raphy and cyclostratigraphy in the Mediterranean Earth PlanetSci Lett 136 475ndash494

Krijgsman W Hilgen FJ Raffi I Sierro FJ Wilson DS 1999Chronology causes and progression of the Messinian SalinityCrisis Nature 400 652ndash655

Montadert L Letouzey J Mauffret A 1978 Messinian eventseismic evidences In Hsuuml KJ Montadert L et al (Eds) InitialReports of the Deep Sea Drilling Project vol 42 (I) USGovernment Printing Washington pp 1037ndash1050

Orszag-Sperber F Rouchy JM (Eds) 1980 Les aspects geacuteodyna-miques du passage Miocegravenendashpliocegravene en Meacutediterraneacutee GeacuteolMeacuted VII 154 pp

Riding R Braga JC Martiacuten JM Saacutenchez-Almazo IM 1998Mediterranean Messinian Salinity Crisis constraints from a

coeval marginal basin Sorbas southeastern Spain Mar Geol146 1ndash20

Robertson AHF Emeis K-C Richter C Camerlenghi A (Eds)1998 Proc ODP Sci Results vol 160 Ocean Drilling ProgramCollege Station TX 817 pp

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Vidal L Bickert T Wefer G Roumlhl U 2002 Late Miocene stableisotope stratigraphy of SE Atlantic ODP Site 1085 relation toMessinian Events Mar Geol 180 71ndash85

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Jean Marie RouchyJean-Pierre SucJean Ferrandini

Michelle FerrandiniE-mail address rouchymnhnfr