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International audience; Detailed, high-resolution documentation of forearc basin fi ll is scarce in the literature. In this geological and geophysical study, we investigated the Pleistocene sedimentary record of the tectonically active Hawke Bay forearc domain of the Hikurangi subduction margin of New Zealand. Interpretation of an extensive seismic-refl ection data set that is correlated with marine cores and onshore geological maps identifi es the detailed stratigraphic architecture of the last ~1.1 m.y. This analysis reveals the infl uences and interactions of tectonic deformation, climate, eustasy, and isostasy on forearc basin sedimentation. Eleven ~100 k.y. depositional sequences are recognized in the basin fi ll, thus highlighting the dominance of Pleistocene climate-eustasy on sequence development. The stacking pattern and isopach maps of sequences exhibit an overall retrogradational trend and an arcward migration of depocenters. These trends progressively develop a basinwide diachronous and composite erosion unconformity formed by the lateral succession and landward encroachment of the 12 sequence-bounding unconformities (S12 to S1). Among these, the S5 surface (ca. 430 ka) is an angular unconformity that separates major megasequences of the sedimentary record. The forearc domain evolved from a series of ridge-parallel basins to a succession of connected basins that have progressively developed around major, growing thrust-faulted ridges since ca. 430 ka. This change in basin confi guration and associated signifi cant increase of the preserved sediment fluxes occurred synchronous with the reactivation of major out-of-sequence thrusts and the completion of the mid-Pleistocene transition.

High-resolution seismic data have been acquired in June 2008 on the Armorican Shelf (AS), in the northern Bay of Biscay, in order to reassess its stratigraphic architecture in detail and to study the impact of eustasy, tectonic and sediment delivery on the margin sedimentary record. Several profiles show fluvial-type incisions of several tens of meters (up to 54 m) associated to a widespread erosion surface. Several hypotheses are proposed for the stratigraphic position of this surface and incisions. We suggest Middle to Late Miocene age. Considering the relatively quiescent tectonic activity of the margin, we infer that the relative sea-level fall responsible of aerial incision on the Miocene shelf is eustasy-related. We propose the attested Serravallian-Tortonian eustatic lowstand (c. 11.6 Ma) as the key event responsible of such erosion and incision. This event marks the early beginning of the high-amplitude sea-level fluctuations that culminated during the Pleistocene and significantly controlled the present day AS morphology. The variability of vertical incision observed along single reaches can be explained by the confluence of several tributaries, the sinuosity of the channel and can be amplified by the unconsolidated nature of the Miocene substratum. The main pathways of the fluvial network corresponding to these buried valleys have been reconstructed and connections to other existing networks are proposed. (C) 2009 Elsevier B.V. All rights reserved.

The fossil record of early vertebrates has been influential in elucidating the evolutionary assembly of the gnathostome bodyplan. Understanding of the timing and tempo of vertebrate innovations remains, however, mired in a literal reading of the fossil record. Early jawless vertebrates (ostracoderms) exhibit restriction to shallow-water environments. The distribution of their stratigraphic occurrences therefore reflects not only flux in diversity, but also secular variation in facies representation of the rock record. Using stratigraphic, phylogenetic and palaeoenvironmental data, we assessed the veracity of the fossil records of the jawless relatives of jawed vertebrates (Osteostraci, Galeaspida, Thelodonti, Heterostraci). Non-random models of fossil recovery potential using Palaeozoic sea-level changes were used to calculate confidence intervals of clade origins. These intervals extend the timescale for possible origins into the Upper Ordovician; these estimates ameliorate the long ghost lineages inferred for Osteostraci, Galeaspida and Heterostraci, given their known stratigraphic occurrences and stem-gnathostome phylogeny. Diversity changes through the Silurian and Devonian were found to lie within the expected limits predicted from estimates of fossil record quality indicating that it is geological, rather than biological factors, that are responsible for shifts in diversity. Environmental restriction also appears to belie ostracoderm extinction and demise rather than competition with jawed vertebrates.

© 2015. This review provides a synopsis of ongoing research and our understanding of the fundamentals of sea-level change today and in the geologic record, especially as illustrated by conditions and processes during the Cretaceous greenhouse climate episode. We give an overview of the state of the art of our understanding on eustatic (global) versus relative (regional) sea level, as well as long-term versus short-term fluctuations and their drivers. In the context of the focus of UNESCO-IUGS/IGCP project 609 on Cretaceous eustatic, short-term sea-level and climate changes, we evaluate the possible evidence for glacio-eustasy versus alternative or additional mechanisms for continental water storage and release for the Cretaceous greenhouse and hothouse phases during which the presence of larger continental ice shields is considered unlikely. Increasing evidence in the literature suggests a correlation between long-period orbital cycles and depositional cycles that reflect sea-level fluctuations, implying a globally synchronized forcing of (eustatic) sea level. Fourth-order depositional sequences seem to be related to a ~. 405. ka periodicity, which most likely represents long-period orbital eccentricity control on sea level and depositional cycles. Third-order cyclicity, expressed as time-synchronous sea level falls of ~. 20 to 110. m on ~. 0.5 to 3.0. Ma timescales in the Cretaceous, are increasingly recognized as connected to climate cycles triggered by long-term astronomical cycles that have periodicity ranging from ~. 1.0 to 2.4. Ma. Future perspectives of research on greenhouse sea-level changes comprise a high-precision time-scale for sequence stratigraphy and eustatic sea-level changes and high-resolution marine to non-marine stratigraphic correlation.

Current interpretation of the Messinian Salinity Crisis (MSC) involves partial “desiccation” of the Mediterranean Sea coupled with the deposition of thick evaporites in the deep basins. New sets of seismic reflection profiles in the western part of the Gulf of Lions confirm the basinward extension of the Messinian erosion and enable the mapping of distinctive seismic markers indicating the Messinian Erosional Surface (or Messinian unconformity), the basin-margin detrital deposits, and the deep evaporite sequence. The geometrical relationship between these three elements and their relationship to the paleogeography of the margin during the MSC provide new information about the evolution of the study area during the Messinian. The Messinian Erosional Surface (MES), commonly correlated with the “desiccation” phase and the deposition of deep evaporites during the apogee of the event, is generally interpreted as a subaerial feature. In the Gulf of Lions, it is a complex diachronic polygenic erosional surface observed at the base of the prograding Plio-Quaternary sequence beneath the shelf and slope; it extends downslope beneath the deep basin Upper Evaporites and the Salt, and possibly correlates conformably with the base of the so-called deep Lower Evaporites. The whole morphology of the MES reflects a buried drainage pattern, supporting the interpretation of fluvial erosion driven by a substantial drop in sea level. Our results also suggest that large submarine gravity flows occurred prior to any significant accumulation of Salt in the basin and prior to the Upper Evaporites. Consequently, interbedded clastic deposits may partly account for the parallel reflectors of the Lower Evaporites. Since river erosion persisted throughout the MSC, the Salt and Upper Evaporite units may also contain a large amount of detrital sediments. The good quality of the new seismic data clearly reveals fan-shaped Messinian deposits in the downstream part of the main Messinian valleys (i.e., the Nile, Var, and Spanish rivers). The depositional scenarios generally involve a substantial sea-level fall coupled with deltaic/prodeltaic accumulations. A chaotic seismic unit (Unit D) filling Messinian lows and extending beneath the Salt within the study area is interpreted as a Messinian clastic unit. We propose a polyphase scenario of detrital fan deposition involving pre-, syn-, and post-Salt deposition in subaqueous/subaerial environments. In the Gulf of Lions, a late Miocene tectonic phase that affected the western shelf also played an important role in controlling (a) the pattern of the Messinian fluvial network, (b) the location of maximum erosion on the shelf, and (c) the location of the detrital fan depocentre downslope.

© 2014. This study presents new data on transgressive-regressive and accommodation-sedimentation regimes in the eastern Russian Plate during the Middle Jurassic-Lower Cretaceous. The proposed generalized scheme illustrating the combined effects of three major factors (eustasy, tectonic "noise", and depositional gradient) controlling the deposition of sequences with different stratal architecture allowed us to quantify the parameters of sedimentation (5S) and accommodation (5A) for second- and third-order cycles. A distinctive feature of the evolution of the Middle Jurassic-Lower Cretaceous sedimentary basin is the excess of accommodation space over sediment supply, which was not conducive to creation of clinoforms. The difference between stacking patterns in individual time intervals and the estimated values of 5A/5S may be indicative of the presence of unidentified stratigraphic breaks in the Bathonian and Late Tithonian-Berriasian, which were accompanied by erosion and reworking of sand strata. The stepwise regressive-transgressive deepening during the Oxfordian-Early Tithonian and transgressive-regressive shallowing during the Late Tithonian-Berriasian were probably caused by short-term manifestations of local tectonic "noise", and depositional hiatuses accompanied by the erosion of missing elements in the structure of third-order cycles. The Lower Cretaceous succession exhibits no mismatch between transgressive-regressive and retrogradational-progradational cycling, which provides another supporting evidence for a quiet tectonoeustatic and sedimentation regime during the Early Cretaceous compared to that of Middle-Late Jurassic time.

© 2014 Elsevier B.V. A methodical approach to identifying major abiotic events in the siliciclastic succession accumulated in the shallow epicontinental basin on the Eastern Russian Platform during the Early Cretaceous is presented. On the basis of a reliable chronostratigraphic framework a comparison between global and regional sea level curves was undertaken. The intervals during which the global and regional sea level curve trends are similar correspond to a predominance of eustasy in the particular basin. Alternatively, tectonic activity dominates during intervals when there is no similarity between the trends of the global and regional sea level curves. Three intervals of noncoincidences of trends of these two curves matched with major tectonic events that took place within the Eastern Russian Platform in the Early Cretaceous: the Early Hauterivian tectonic uplift, subsequent Late Hauterivian subsidence and the Late Albian uplift. The main consequences of the tectonic activity were two large regional unconformities and hiati. The comparison of main global and regional sea level trends also reveals major climatic events. "The cold snaps" that occurred during the Early Cretaceous greenhouse world (Hu et al., 2012) coincided with simultaneous global and regional sea level lowstands, peak shallowing of the basin and the almost complete absence of sediments. "The cold snap" is identified in the Late Aptian sedimentary sequences on the Eastern Russian Platform.

Stratigraphie analyses and the presence of submerged ruins at Fos have allowed the identification of five coastlines dating from 6500 В P. The study and comparison between bathymétrie indicators (faunistic and sedimentological) from sandy substrates in the Gulf of Fos and the curve obtained on rocky substrates of Provence and Corsica by J. Laborel (19941 indicate tectonic movements evaluated at 0.01 mm/yr and 0.37 mm/yr since 4000 BP, and 0.2 mm/yr and 0.5 mm/yr since the first century AD. These ground movements seem to have caused sedimentary influxes since 6120 ± 55 BP and after 2100 ± 45 BP, which would suggest that one of the mouths of the Rhône was closer to the Gulf of Fos., Résumé L'analyse stratigraphique et la présence de vestiges immergés à Fos ont permis d'identifier cinq lignes de rivage depuis 6500 В P. L'étude d'indicateurs bathymétriques (faunistiques et sédimentologiques) sur les substrats meubles du Golfe de Fos et leur comparaison avec la courbe établie sur substrat rocheux en Provence et en Corse par J. Laborel (1994) ont mis en évidence des mouvements tectoniques verticaux négatifs évalués à 0,01 mm/an et 0,37 mm/an depuis 4000 BP, et à 0,2 mm/an et 0,5 mm/an depuis le Ier siècle. Ces mouvements du sol semblent induire une réponse sédimentaire, à partir de 6120 ± 55 BP et après 2100 BP ± 45, qui semblerait indiquer l'apport d'un exutoire du Rhône se rapprochant du golfe de Fos., Vella Claude, Bourcier Michel. Stades ultimes de la montée holocène du niveau marin et subsidence tectonique dans le golfe de Fos (Provence, France)/Last stages of Holocene sea-level rise and tectonic subsidence in the Gulf of Fos (Provence, France). In: Géomorphologie : relief, processus, environnement, Juillet 1998, vol. 4, n°2. pp. 141-154.

The upper Albian to lower Cenomanian succession in northeastern British Columbia was deposited in the proximal foredeep and is greatly vertically expanded relative to the more eastern part of the basin. The study interval has a wedge-shaped geometry, and is ~780 m thick in the west and thins dramatically to ~280 metres over a distance of ~170 km. Rapid facies changes result in lithostratigraphic units being strongly diachronous. In order to determine depositional history, the present study subdivided the Upper Fort St. John Group into 16 genetically-related allomembers. The new allostratigraphic correlations established in this thesis combined with previous studies, permit the reconstruction of lateral facies changes from the western shoreline of the Western Interior Seaway in the proximal foredeep to the forebulge in central Alberta, over a distance of about 800 km. The Upper Viking, Westgate and Fish Scales alloformations collectively span approximately 2.7 Myr. The stratal geometry of the studied interval can be interpreted to be the result of two pulses of flexural subsidence (recorded by units VD and WA, and units WD, FA and FB) separated by a period of more subdued subsidence (units WB and FC). The stratigraphic surfaces in the studied interval are of regional extent, and can be correlated for between 300-1000 km. Almost all flooding surfaces can be traced throughout the study area (50 000 km2). The sedimentological and stratigraphic evidence indicates that the proximal foredeep was occupied by a shallow, low-gradient, storm-dominated ramp. The abundance of waveinfluenced structures (e.g. swaley and hummocky cross-stratification, wave and current ripples) suggests strong wave-reworking of sediment on a shallow marine ramp. The deposition on muddy portion of the shelf is interpreted to have been dependent on waveenhanced sediment gravity/geostrophic flows. Along-shelf transport was controlled by geostrophic flows towards the southeast. At least 16 major sequences were detectable on a regional scale; sequences have an average periodicity of 125-170 kyr. Facies successions and regional stratal geometry suggest relative sea-level fluctuations were of the order of 10-30 m which, on a time-scale of the order of 100 kyr, can only be explained by a glacio-eustatic mechanism.

The Turonian-Coniacian Cardium Formation of southern Alberta consists of marine sandstone and mudstone, deposited in a foreland basin over ~2.3 m.y. The formation thins from 150 m in the western foredeep to 50 m 350 km to the east. Correlation of 10 regional flooding surfaces in >1200 well logs and 25 outcrops provides an allostratigraphic framework. Mapping of two previously-unrecognized erosion surfaces (E5.2 and E5.5) reveals additional complexity within sandstone of the Raven River Member. Facies successions coarsen upwards from thinly-bedded and bioturbated mudstone, to heterolithic facies (either bioturbated or bedded), to clean sandstone. Where conglomerate unconformably overlies this succession, the base of the conglomerate marks a regional erosion surface. A tabular geometry, and wave-formed sedimentary structures even in distal settings, indicate deposition on a very low gradient shelf within the mud accommodation envelope (~70 m), and at times, within effective wave-base for sand (~40 m). Isopach maps reveal two pulses of isostatic subsidence that were separated by a period of tectonic quiescence. The locus of flexural subsidence shifted southward by >200 kilometres in 900 kilometres along strike, ~300 kilometres offshore, and between depocentres, suggesting a eustatic mechanism. Facies relationships across flooding surfaces suggest that eustatic fluctuations had a magnitude of ~12 m and a frequency of ~250 k.y., and are therefore best explained by glacioeustasy.

12 páginas, 9 figuras, 2 tablas., Well-preserved Quaternary staircased marine terraces appear on Ras Leona limestone relief. This is a peculiar sector of the Betic-Rif Cordillera, lying in the four-way junction between the Atlantic and the Mediterranean, and Europe and Africa. The age and altitude correlation of the Ras Leona terraces with travertine-covered lateral equivalent terraces fashioned in the neighbouring Beni Younech area, and comparison with those along the Moroccan Atlantic coasts, would suggest that the Ras Leona terraces were mainly formed by eustatic factors. The importance of the eustasy is supported by further comparisons with Spanish and Moroccan Mediterranean terraces and with different marine terraces developed on passive-margin coasts around the world. A tectonic event occurred mainly during the period between the formation of the Maarifian and the Ouljian terraces (i.e., between 370 and 150 ka). The moderate Quaternary tectonic uplift deduced from the marine terraces and its comparison with uplifted marine terraces developed in active subduction setting disagrees with the model of an active eastwards subduction below the Gibraltar tectonic arc., This paper forms part of the projects A/024878/ 09 (AECID, CGL2007-60535, CGL2009-07721 and CSD2006-00041 (MEC), P06RNM-01521, RNM-024 and 148 (Junta de Andalucía).

International audience; 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 synsedimentary 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.

The contributions of eustasy and tectonics to the development of stratigraphic sequences are commonly hard to discern, and this has been a controversial topic that is still being debated. New data are therefore necessary to improve our understanding of the factors that govern sedimentary cyclicity. Data from the subsiding Venice and the uplifting Crotone areas in Italy allow the recognition of the different effects of Late Quaternary glacio-eustatic changes and regional tectonics on sequence architecture at different temporal scales. Shallow-marine small-scale sequences linked to short-term glacio-eustatic changes at the scale of the marine isotope substage cyclicity (10000 years) show features that developed irrespective of the local conditions of subsidence or uplift, such as a modest thickness, a similar organization of facies and thin transgressive deposits. In contrast, lower frequency composite sequences at the scale of 100000 years show strongly different architectures and stacking patterns depending on the regional tectonic context: downstepping in uplifting areas and aggradational in subsiding areas. The present results, therefore, highlight that only the architecture of small-scale sequences showing a periodicity of about 20 and 40 ka appears to be dominated by the glacio-eustatic variable, because of the very high rates of sea-level change characterizing the substage cyclicity, which overprints the regional tectonic signal.

International audience; This study synthesizes the stratigraphic behavior of the whole eastern Niger Delta during the Plio-Pleistocene and discusses controls on deposition by eustasy, subsidence and sediment supply at various scales. The sequence stratigraphic architecture is determined by integrating the whole sedimentary system from the coastal plain down to the abyssal plain. We combined structural geology, sedimentology biostratigraphy, and seismic stratigraphy. Data included 2D regional sections connected by 3D seismic surveys and 45 well-logs for lithologic calibration and well-cuttings for biostratigraphic calibration. We identified three sequence orders in the stratigraphic architecture of the eastern Niger Delta and calibrated their biostratigraphic ages into absolute ages using two end-member models to estimate uncertainties. We discuss their causes and propose that the major influence was climate-driven eustasy for both the (i) short-duration (a duration around 0.1 to 0.4 My) and (ii) long-duration progradation/retrogradation sequences (around x1 My in duration). Two different modes of climatic control are suggested for the (iii) long-term stratigraphic trend over the Plio-Pleistocene: global climate-driven eustatic variations for the initial progradation until 2.5 Myr ago and a regional climate change (e.g. the warming of the East Atlantic and the aridification of western Africa) for the following aggradation/retrogradation period, controlled by a decrease in the sedimentary supply to the eastern delta counteracting the ongoing eustatic fall.

Synrift stratigraphy on a normal fault block is subdivided into three groups. The Lower group is composed of continental sediments (fluvio-lacustrine). The Middle group contains the giant Gilbert-type fan deltas and their associated fine-grained facies. The Upper group is composed of the recent to present day Gilbert-deltas and superficial deposits. The Lower group is marked by a low subsidence rate on the young Pirgaki fault and some secondary faults. A marked increase in subsidence rate mark the transition to the Middle group. It is proposed that the increase in subsidence rate is due to the connexion between two major faults. The Upper group was deposited during uplift of the study area in the footwall of the Helike fault. It is suggested that the giant Kerinitis Gilbert-type fan delta was deposited during the Early to early Middle Pleistocene, under marine conditions. Facies characterizing a range of depositional processes are assigned to four facies associations: topset, foreset, bottomset and prodelta. The stratal architecture is composed of eleven Key Stratal Surfaces (KSS) separating eleven Stratal Units (SU). In this subsidence-dominated system, each SU records a highstand period and principally a period of decreasing eustatic sea level. The KSS, record transgressions that took place in periods of rapid sea level rise. The eustatic signal, controlling the deposition of the SU is of higher frequency than the tectonic signal, which controlled four stages of delta growth. The four delta growth stages are linked with the initiation, maximum growth and the abrupt death of the Pirgaki-Kerinitis fault system., La stratigraphie synrift du bloc de faille est divisée en trois groupes stratigraphiques, représentant une épaisseur de 1624 m. Le Groupe inférieur est composé de sédiments fluvio-lacustres, le Groupe moyen comporte les Gilbert-deltas géants et leurs faciès fins associés, le Groupe supérieur est formé de Gilbert-deltas récents à actuels ainsi que de formations superficielles. La discordance basale de l'Unité du prérift présente une paléotopographie. La phase d'extension précoce (Groupe inférieur) est caractérisée par une très faible subsidence assurée par l'activité précoce de la faille de Pirgaki et des failles mineures. La transition avec la phase d'extension principale (Groupe moyen) est marquée par un approfondissement du bassin ainsi que par une augmentation du taux de subsidence. La phase d'abandon et de soulèvement du bloc (Groupe supérieur) est caractérisée par des évènements de creusement-comblement. Le Gilbert-delta géant de Kerinitis se serait déposé dans la période Pléistocène inférieur-Pléistocène moyen, en milieu marin. L'étude de la sédimentologie de faciès a permis de mettre en évidence quatre associations de faciès : topset, foreset, bottomset, prodelta. L'architecture stratigraphique est composée de onze Unités Stratigraphiques (SU) séparées par onze Surfaces Stratigraphiques (KSS). Dans un contexte de création continue d'espace d'accommodation, les SU se déposent pendant les maxima et les périodes de chute du niveau marin. Les KSS se mettent en place pendant des périodes d'augmentation du niveau marin. Les quatres étapes de construction du Gilbert-delta de Kerinitis ont enregistré le début, le maximum et l'arrêt de l'activité du système de failles.

Topography growth and sediment fluxes in active subduction margin settings are poorly understood. Geological record is often scarce or hardly accessible as a result of intensive deformation. The Hawke Bay forearc basin of the Hikurangi margin in New Zealand is well suited for studying morphstructural evolution. It is well preserved, partly emerged and affected by active tectonic deformation during Pleistocene stage for which we have well dated series and well-known climate and eustasy. The multidisciplinary approach, integrating offshore and onshore seismic interpretations, well and core data, geological mapping and sedimentological sections, results in the establishment of a detailed stratigraphic scheme for the last 1.1 Ma forearc basin fill. The stratigraphy shows a complex stack of 11 eustasy-driven depositional sequences (20, 40 and 100 ka periodicity). These sequences are preserved in sub-basins that are bounded by active thrust structures. Each sequence is characterized by important changes of the paleoenvironment that evolves between the two extremes of the glacial maximum and the interglacial optimum. Thus, the Hawke Bay forearc domain shows segmentation in sub-basins separated by tectonic ridges during sea level lows that become submerged during sea level highs. Over 100 ka timescale, deformation along active structures together with isostasy are responsible of a progressive migration of sequence depocenters towards the arc within the sub-basins. Calculation of sediment volumes preserved for each of the 11 sequences allows the estimation of the sediment fluxes that transit throughout the forearc domain during the last 1.1 Ma. Fluxes vary from c. 3 to c. 6 Mt.a-1. These long-term variations (100 ka to 1 Ma timescale ranges) are attributed to changes in the forearc domain tectonic configuration (strain rates and active structure distribution). They reflect the ability of sub-basin to retain sediments. Short-term variations of fluxes (

A little known marine Miocene (Messinian) succession in the Hyblean region of south eastern Sicily preserves a carbonate ramp sequence which developed on the tectonically stable foreland margins of the African Plate (Pelagian Block). The ramp (Monte Carrubba Formation) was distally steepened and contained a shoalwater barrier and lagoonal inner ramp complex. The outer ramp is poorly preserved though distal deep water ramp facies (Tellaro Formation) in the south Hyblean region preserve a full Globorotalia mediterranea Subzone and major part of the Globigerina multiloba Subzone succession. This ramp sequence faithfully records the subtle interplay between the global eustatic curve and internal Palaeomediterranean base-level signatures for the Late Miocene. The earliest second order Palaeomediterranean lowstand occurred in the Late Tortonian at about 7.3 Ma and a second occurred at about 6.75 Ma within the Early Messinian G. mediterranea Subzone. Both were in the order of 40 m and global sea-level was probably restored to the Palaeomediterranean after the lowstands. Although the overriding control at the time was the global eustatic curve, harmonic discrepencies between it and the Palaeomediterranean curve resulted from constriction of the Atlantic connection during the latest Tortonian. From about 6.4 Ma until about 5.96 Ma increasingly restricted conditions developed across the Monte Carrubba inner ramp. These faithfully reflect many second order, constriction-driven Palaeomediterranean sea-level oscillations which were superimposed on to the falling global signal as the connecting Atlantic seaways became constricted. These oscillations resulted in major reductions in planktonic faunal diversity within the outer ramp, followed by total emergence of the inner ramp by about 6.05 Ma. Marine deposition continued until about 5.96 Ma in the southern part of the Hyblean region. However, between 6.05 Ma and about 5.6 Ma the amplitude of successive Palaeomediterranean sea-level oscillations increased to over 100 m, causing prolonged periods of total Palaeomediterranean isolation. The Hyblean carbonate suite also contains post-Messinian Salinity Crisis (post-MSC) ‘Lago Mare’ highstand deposits which are developed unconformably above the Monte Carrubba Formation. The widespread distribution of hyposaline to near-marine Congeria faunas within the Lago Mare episode argues for high post-MSC Mediterranean water levels in the Central Mediterranean Late Messinian. In this article we draw together disparate regional evidence from this stable foreland setting and assimilate it with published data from regions lying on the European Plate in order to demonstrate that the tectonically stable Monte Carrubba succession provides an unambiguous record of Central Palaeomediterranean base-level change during the Messinian. Furthermore, the post-MSC sequence demonstrates a prolonged Mediterranean base-level rise throughout the Late Messinian, leaving little readjustment necessary in order to restore Mediterranean base-level to global water levels in basal Pliocene times.

The detailed study of reservoir (oil/gas, CO2 and waste storage...) architecture is first a stratigraphic challenge, more specifically for continental series. The geometry of such deposits is under the influence of three main factors: sea-level changes (eustasy), tectonics and climate. This study aims at understanding their role in the architecture of the continental deposits, in the Miocene (~13.5-23 Ma) of the Digne Foreland Basin (Southeast France). These deposits were chosen because of a well constrained stratigraphy and good outcrops conditions. Sequence stratigraphy of the succession lead to a distinction between a northern and a southern zone. The former recorded seven third order-sequences, whereas two of them disappear towards the south. Regional tectonics played on the amplitude and the age of sequences, when compared with the eustatic charts. It is interpreted as the depocentre migration during the basin infilling. Climate played a role a various scales of time. The Climatic Optimum of the Middle Miocene (14.6-16.5 Ma) is marked by three global events: the carbon isotope excursion of the "Monterey Event", a major transgression (Langian) and the climax of the Avicennia mangrove development. Climato-eustatic origin of the third order sequences in the Langhian-Serravallian time interval is shown by comparison of the sequence stratigraphy and palynology data. At the scale of the Milankovitch cycles, eccentricity cycles were observed in the frequency of marine incursions, precession and obliquity cycles were reported from the distribution and development of paleosols, thanks to a direct comparison to the insolation curve., Le besoin de connaître toujours plus finement les réservoirs (pétrole/gaz, stockage du CO2, des déchets...) se heurte au problème de la résolution temporelle (stratigraphique), notamment pour les séries sédimentaires continentales. Leur géométrie dépend essentiellement de trois facteurs: les variations du niveau marin (eustatisme), la tectonique et le climat. Cette étude vise à comprendre leur rôle respectif dans l'architecture des dépôts continentaux miocènes (~13,5-23 Ma) du bassin de Digne, dont la stratigraphie est bien établie. L'analyse séquentielle des dépôts nous a permis de distinguer une zone Nord où sept séquences de 3e ordre sont enregistrées, et une zone Sud où la tectonique locale en a fait disparaître deux. La tectonique régionale a joué sur l'amplitude et l'âge des séquences en regard des correspondances établies avec la charte eustatique. Ses effets traduisent le déplacement des dépôtcentres au cours du remplissage du bassin. L'influence du climat a joué à différentes échelles de temps. A celle de l'Optimum Climatique du Miocène (14,6-16,5 Ma), caractérisé par trois phénomènes globaux (l'excursion isotopique du 13C - Monterey Event; un maximum transgressif; le développement maximal de la mangrove à Avicennia). A celle des cycles de 3e ordre du Langhien-Serravallien, dont l'origine climato-eustatique est attestée par la comparaison du découpage séquentiel avec l'analyse pollinique. A l'échelle des cycles de Milankovitch, dont ceux d'excentricité ont été observés dans les incursions marines, les cycles de précession et d'obliquité ayant été reconnus dans la distribution et le développement des paléosols, par comparaison directe avec le signal d'insolation.

The detailed study of reservoir (oil/gas, CO2 and waste storage...) architecture is first a stratigraphic challenge, more specifically for continental series. The geometry of such deposits is under the influence of three main factors: sea-level changes (eustasy), tectonics and climate. This study aims at understanding their role in the architecture of the continental deposits, in the Miocene (~13.5-23 Ma) of the Digne Foreland Basin (Southeast France). These deposits were chosen because of a well constrained stratigraphy and good outcrops conditions. Sequence stratigraphy of the succession lead to a distinction between a northern and a southern zone. The former recorded seven third order-sequences, whereas two of them disappear towards the south. Regional tectonics played on the amplitude and the age of sequences, when compared with the eustatic charts. It is interpreted as the depocentre migration during the basin infilling. Climate played a role a various scales of time. The Climatic Optimum of the Middle Miocene (14.6-16.5 Ma) is marked by three global events: the carbon isotope excursion of the "Monterey Event", a major transgression (Langian) and the climax of the Avicennia mangrove development. Climato-eustatic origin of the third order sequences in the Langhian-Serravallian time interval is shown by comparison of the sequence stratigraphy and palynology data. At the scale of the Milankovitch cycles, eccentricity cycles were observed in the frequency of marine incursions, precession and obliquity cycles were reported from the distribution and development of paleosols, thanks to a direct comparison to the insolation curve., Le besoin de connaître toujours plus finement les réservoirs (pétrole/gaz, stockage du CO2, des déchets...) se heurte au problème de la résolution temporelle (stratigraphique), notamment pour les séries sédimentaires continentales. Leur géométrie dépend essentiellement de trois facteurs: les variations du niveau marin (eustatisme), la tectonique et le climat. Cette étude vise à comprendre leur rôle respectif dans l'architecture des dépôts continentaux miocènes (~13,5-23 Ma) du bassin de Digne, dont la stratigraphie est bien établie. L'analyse séquentielle des dépôts nous a permis de distinguer une zone Nord où sept séquences de 3e ordre sont enregistrées, et une zone Sud où la tectonique locale en a fait disparaître deux. La tectonique régionale a joué sur l'amplitude et l'âge des séquences en regard des correspondances établies avec la charte eustatique. Ses effets traduisent le déplacement des dépôtcentres au cours du remplissage du bassin. L'influence du climat a joué à différentes échelles de temps. A celle de l'Optimum Climatique du Miocène (14,6-16,5 Ma), caractérisé par trois phénomènes globaux (l'excursion isotopique du 13C - Monterey Event; un maximum transgressif; le développement maximal de la mangrove à Avicennia). A celle des cycles de 3e ordre du Langhien-Serravallien, dont l'origine climato-eustatique est attestée par la comparaison du découpage séquentiel avec l'analyse pollinique. A l'échelle des cycles de Milankovitch, dont ceux d'excentricité ont été observés dans les incursions marines, les cycles de précession et d'obliquité ayant été reconnus dans la distribution et le développement des paléosols, par comparaison directe avec le signal d'insolation.

4 páginas, 2 figuras.-- Trabajo presentado en la 39ª Sesión Científica, Puertollano, Ciudad Real, 2005., The existence of many marine abrasional forms, with their different heights and grades of certainty, is described in the coastline comprise between Maro (Málaga province) and Castell de Ferro (Granada province). The heights vary between the present sea level till near 100 m. These values are comparable to others existing in more western andalusian coasts. Up till now there are not direct data to establish a chronology in the study area, but in any case the heights of these marine forms are clearly attributable to the eustatic oscilations, more that to the tectonics, which, for recent times, have much more lesser values of vertical displacements., Trabajo realizado en el marco de los proyectos CGL2004-01636 y CGL2004- 03333/BTE del MEC y el grupo RNM 217 de la Junta de Andalucía.

The existence of many marine abrasional forms, with their different heights and grades of certainty, is described in the coastline comprise between Maro (Málaga province) and Castell de Ferro (Granada province). The heights vary between the present sea level till near 100 m. These values are comparable to others existing in more western andalusian coasts. Up till now there are not direct data to establish a chronology in the study area, but in any case the heights of these marine forms are clearly attributable to the eustatic oscilations, more that to the tectonics, which, for recent times, have much more lesser values of vertical displacements

Venetian land subsidence, both natural and induced by groundwater withdrawal, and northern Adriatic Sea eustasy have caused 23 cm of relative land subsidence referred to as the mean sea level over the last 100 years. This relative elevation loss has been vital for Venice's existence, inasmuch as Venice lives in the water. After a short overview of the process during the past decades, the actual trend of relative ground-sea movement is presented by integrating high precision leveling, remote sensing measurements and tide gauge records. Geodetic and Interferometric Synthetic Aperture Radar (InSAR) data evidence the present ground stability of the central part of the lagoon, where the city of Venice is located, and slight sinking rates at the northern and southern extremities of the lagoon edges (3–5 mm/year) and at some places in the central and northern littorals (1–3 mm/year). At the same time, the latest tide gauge records indicate a renewal in the sea-level rising trend. Within the average secular eustatic rate of 1.13 mm/year, the value of −0.89 mm/year, observed near Venice during the period 1971–1993, increased to 1.53 mm/year when adding the records up to 2002.

[ES] El Mb. Arenas y Arcillas de El Burgal aflora en el SE de la Cordillera Ibérica. Comprende principalmente arenas (arcosas) de grano grueso a fino blancas y ocres, con intercalaciones de niveles de cantos de cuarcita de tamaño medio, lutitas abigarradas y localmente niveles de carbón (lignito). El espesor de esta unidas varía entre 5 y 85 m. en el área estudiada. La distribución de los sedimentos está claramente controlada por fracturas sinsedimentarias con orientación NO-SE, que condicionaron durante el Cretácico Inferior el desarrollo del rift en laCuenca Ibérica. El estudio detallado de facies y asociaciones de facies en 33 secciones estratigráficas... (Leer más) y el mapa de isopacas, indica que el Mb. El Burgal se depositó en la zona N mediante sistemas fluviales arenosos que evolucionaron, hacia las zonas central y meridional, a ambientes de interacción fluvial y mareal, donde los canales fluviales son frecuentemente truncados por canales mareales. Los ambientes fluviales están representados por sedimentos de carga de fondo depositados como barras que rellenan canales de baja sinuosidad pero que también en ocasiones son de alta sinuosidad. Los depósitos de derrame son frecuentes en la zona meridional, y muestran un complejo de cuerpos arenosos tabulares que alcanzan extensiones laterales de varias decenas de metros. En el área de transición fluvio-marina, aparecen depósitos fluviales de tipo meandriforme arenoso que cortan horizontes de suelos y niveles de carbón situados en la llanura de inundación y, verticalmente, alternan con delgados niveles marinos someros. Estos últimos, pertenecientes a las facies carbonatadas urgonianas, alcanzan mayor desarrollo en el área meridional. La sedimentación del Mb. El Burgal estuvo controlada por la interacción de factores tectónicos y eustáticos, que delerminaron el desarrollo de superficies de erosión, de niveles de suelos y costras ferruginosas, discordancias, cambios laterales de facies y migración de los cinturones de facies. Estos factores de control principales, también condicionaron el desarrollo de dos secuencias de depósito en las que se pueden reconocer bien los cortejos sedimentarios de bajo nivel, transgresivo y alto nivel del mar. Aportes siliciclásticos similares también se produjeron en otras zonas de este ámbito paleogeográfico durante ese intervalo de tiempo, zonas que fueron sometidas a esfuerzos tectónicos distensivos probablemente asociados a la apertura del Atlántico Norte., [EN] The Aptian El Burgal Mb. crops out in the SE Iberian Ranges (Central Spain). It is mainly comprised of fine to coarse-grained, white and ochre sandstones (arkoses) with intercalated levels of medium-sized, rounded quartzite pebbles, red mudstones and local coal (lignite) horizons. The thickness of the member changes abruptly from 5 m to 85 m in the study area. Dispersion of the sediments are clearly controlled by the NW-SE fault orientation that conditioned the Lower Cretaceous rift development in the Iberian Basin. Detailed study of isopachs, 33 logs and 6 facies associations indicate that the El Burgal Mb. was deposited from northern to southern... (Leer más) zones respectively within sandy fluvial systems and fluvial-wave-tide interaction environments, commonly truncated by tidal channels. The fluvial environments are represented by bedload sediments, deposited as bars that fill channels of mainly low but also of high sinuosity. Crevasse splays are frequent, showing long complex sheet-sandstone bodies interbeded with the channel fills in the northern area. The fluvio-marine transitional zone is located in the central area, where sandy fluvial meandering deposits cut soil horizons and coal seams in flood plain areas and alternate with shallow water marine sediments of Urgonian carbonate facies in the southern zone.Sedimentation of the El Burgal Mb. was clearly controlled by tectonic and eustatic factors. The interaction between both factors was responsible of erosive surfaces, soil and crust levels development, unconformities and lateral facies changes and facies belts migration. These factors also conditioned the development of two depositional sequences where lowstand, transgressive and highstand systems tracts are well recognized. Similar siliciclastic deposits also occurred in other parts of this area that, during that time, underwent stress-induced tectonic episodes probably associates with a large-scale tectonic event related with the so-called opening of the Atlantic.

The ostracode response to oceanographic changes during the Paleocene-Eocene thermal maximum (PETM, ca. 55 Ma) is largely unknown. The Gebel Duwi section (Egypt) provides a detailed ostracode record across the PETM in a middle neritic setting. Quantitative analysis of this record reveals two significant results. (1) The PETM is marked by a sharp faunal turnover, as indicated by abundance changes, local extinctions, and immigrations. This turnover punctuated a gradual basin-wide faunal transition. (2) During the ;60 k.y. period prior to the PETM, relative sea level fell rapidly by ;15 m. This sea-level fall was followed by an ;20 m sea-level rise during the PETM. A possible eustatic control on these fluctuations suggests the presence of a cryosphere and variations in its size during this time of global warmth. ispartof: Geology vol:30 issue:1 pages:23-26 status: published

Se aborda el estudio del karst litoral en la mitad oriental de Mallorca, acometiéndolo desde una perspectiva pluridisciplinar que se ocupa tanto de diferentes aspectos de su modelado epigeo como, sobre todo, de las peculiaridades del rico endokarst existente en el área estudiada. Con respecto a la morfogénesis exokárstica del área, son tratados a lo largo de la presente memoria los siguientes aspectos: el lapiaz litoral, la presencia de calas y sus barrancos asociados y, finalmente, la influencia del paleokarst fini-Mioceno en la morfología de la línea de costa.Los fenómenos subterráneos de Mallorca son estudiados desde un punto de vista genético, describiendo al mismo tiempo las características diferenciales del endokarst en las dos regiones naturales implicadas: las Serres de Llevant y el Migjorn. La atención ha sido focalizada en las numerosas cavidades de la última región kárstica mencionada, la cual destaca por la riqueza y las peculiaridades morfogénicas de sus cavidades hipogeas naturales.Las investigaciones se han centrado en el análisis de las interferencias entre el modelado endokárstico y la dinámica litoral, aportándose datos novedosos sobre un abanico muy variado de materias. Los temas que son abordados abarcan desde aspectos geoquímicos y espeleogenéticos en acuíferos carbonatados litorales, hasta abundantes ejemplos de cuevas mixtas de génesis kárstico-marina. Se presta una particular atención a los rellenos alóctonos de las cavernas costeras, que incluyen tanto materiales detríticos (calcarenitas marinas y/o eólicas) como restos paleontológicos de vertebrados endémicos. Los rellenos autóctonos presentes en las cavidades (espeleotemas, en general) ofrecen especial interés, debido a las grandes posibilidades geocronológicas derivadas de su datación radiométrica. Las interferencias analizadas entre karst y litoral -las cuales han estado controladas en todo momento por la posición del nivel marino- permiten una reconstrucción detallada de la evolución del endokarst a lo largo del Plio-Cuaternario.El mayor interés de los trabajos realizados radica en las valiosas informaciones crono-estratigráficas obtenidas en relación con las oscilaciones pleistocénicas del nivel marino. En concreto, el estudio de los espeleotemas freáticos ha mostrado que éstos constituyen un excelente registro de la historia del nivel del Mediterráneo, durante el Pleistoceno Medio y Superior y el Holoceno. Conviene resaltar los novedosos datos aportados por aquellos espeleotemas freáticos que han sido recolectados por debajo de la presente cota ±0 metros; estas cristalizaciones nos documentan, con gran detalle, las pulsaciones regresivas experimentadas por el nivel marino, las cuales eran bastante desconocidas hasta el momento. Este tipo de depósitos secundarios propios de las cuevas kársticas litorales han sido estudiados mediante diversas técnicas (dataciones radiométricas Th/U, mediciones de ESR, microscopía óptica y electrónica, análisis de isótopos estables...) con vistas a la obtención de datos cronológicos, paleoclimáticos, mineralógicos y cristalográficos precisos.De particular relevancia son las curvas eustáticas propuestas para los últimos 300 ka, en el Mediterráneo occidental, las cuales presentan un detalle fuera de lo común en el rango de edad comprendido entre 150 y 60 ka BP. Centrando nuestra atención en el último evento interglacial (estadio isotópico 5) es posible distinguir cuatro picos transgresivos, situados entre 130 y 80 ka BP, separados por tres pulsaciones frías que produjeron descensos bruscos del nivel del Mediterráneo, de más de 20 metros de amplitud. Las tasas deducidas de ascenso y/o descenso del nivel marino son del orden de 4 metros/ka, poniendo de manifiesto las importantes crisis climáticas acontecidas durante el Pleistoceno Superior., This thesis deals with the study of littoral karst in the eastern half of Mallorca island, by means of a cross-disciplinary approach that takes into account both the different aspects of its surface modelling (littoral karren, coves and associated gullies, paleokarst features) and the singularities of the rich endokarst existing in this area. The subterranean phenomena in the island are studied from a genetical point of view, describing at the same time the differential characteristics of endokarst in the two natural regions involved: Serres de Llevant and, particularly, the Migjorn area. Our investigations have been specially addressed to analyze the interferences between endokarstic modelling and littoral dynamics. The topics that are discussed cover from geochemical and speleogenetical aspects in coastal carbonate aquifers, to abundant examples of mixed cavities which are karstic-marine in origin. Particular attention is paid to the alochtonous infillings existing in coastal caves, that include both detritic materials (marine and/or eolian calcarenites) and paleontological remains of endemic vertebrates.Specifically, the study of phreatic speleothems has shown that these deposits are an excellent record of Mediterranean sea-level history, during Middle and Upper Pleistocene and Holocene. Abundant data supplied by phreatic speleothems collected below the present-day ±0 metres must be thrown into relief; these crystallizations document us -with a great detail- the regressive pulsations experienced by the sea-level. This deposits has been studied by means of several techniques (radiometric Th/U datings, ESR measurements, optical and electronic microscopy, X-ray diffraction, stable isotope analysis.) in order to obtain precise chronological, paleoclimatological, mineralogical and crystallographical data.Eustatic curves proposed for the last 300 ka in the western Mediterranean are significant. Centering our attention in the last interglacial event (isotopical stage 5) four transgressive peaks are distinguished, situated between 130 and 80 ka BP, separated by three cold pulsations that produced abrupt Mediterranean sea lowerings, about 20 metres in amplitude. The deduced mean rates of sea-level rise and/or lowering are in the order of 4 metres/ka.

This thesis reports a series of flume tank experiments that were conducted to model the stratigraphic evolution of river-delta systems. Chapter 1 introduces the river-delta sedimentary system that is subject of modelling. The chapter also includes an overview of previous research and the summary and conclusions of the thesis. Chapter 2 demonstrates the experimental method and applied scaling strategy of the analogue experiments using the Quaternary Colorado Delta evolution as a real-world prototype. Chapter 3 investigates the fluvial response to imposed sea-level changes by a set of 18 analogue experiments with sea-level change as the only independent variable. Chapter 4 is a case study of the stratigraphy of the Imo River Oil Field, Nigeria, where deltaic sediments have been dissected by a listric growth fault during deposition. The stratigraphic features of the model run are compared with the Imo River Field prototype, other growth-faulted settings, extensional synrift tectonic settings and are finally discussed in terms of hydrocarbon potential. The final part of the thesis contains an appendix on sediment transport properties of the model and the references and acknowledgments section.

The causal relationship between the Cenozoic sequence development in the southeastern North Sea Basin and sea-level changes, climatic fluctuations and tectonic events is unravelled by relating variations in the relative sea level and base level, based on interpretations of seismic surveys, to published δ 18 O variations and eustatic changes. The latter curve is based on the Earth9s orbital forcing, and here informally termed as the GSI curve. The analysis shows that the Cenozoic sequence development in the southeastern North Sea was influenced by climatically and tectonically induced sea-level changes. The major Cenozoic sequence stratigraphic boundaries (lower order) are highly influenced by tectonic events, e.g. uplift of Fennoscandia and increased subsidence rates in the basin centre. Reactivation of Mesozoic fault zones controlled the deposition of minor sand bodies transported to the centre of the basin during the Late Palaeocene by mass flows. The location of an Oligocene mound structure, which constitutes part of a sequence, is controlled by the overall palaeotopography of the basin and local fault-related depressions. Correlation between (i) the ages of our sequences and the δ 18 O variations in the Oligocene succession, and (ii) the GSI curve and the base-level fluctuations of the late Miocene and younger sequences, show that the generation of the higher order sequence boundaries were driven by glacio-eustatic sea-level changes. A climatic control of the sequence formation due to glacio-eustatic sea level changes is therefore suggested for the Oligocene and Pliocene sequences, and probably also for the Upper Miocene sequences.

Many basins are filled under the influence of tectonics and variable climatically driven processes. Unravelling the relative contributions of these is generally easier in fossiliferous sequences if faunal diversity patterns are considered in conjunction with lithofacies analysis. This approach has been successfully applied to Late Miocene strata of Sicily, where progressive restriction and desiccation within the Sicilian Caltanissetta region occurred under a semi-arid climate during the Messinian Stage. This restriction was partly due to Antarctic cooling which produced Palaeo-Mediterranean sea-level oscillations during the Early Messinian, as a prelude to closure of the Atlantic connections. In addition, regions within this Afro-European plate collision zone were also subjected to syndepositional tectonic deformation associated with progressive perched basin development above foreland (south) verging thrust sheets. The relative impacts of climatic (eustatic) versus tectonic control on sedimentation patterns within these perched basins has been debated at length. However, progress towards resolving this problem by a combined approach involving lithofacies analysis, and faunal phase analysis provides clues for separating the effects of the controlling factors. Faunal phase analysis identifies general faunal associations with minimal emphasis on species diversity. The resulting ‘phase’ plots for Early Messinian strata appear to be transgression skewed when controlled by eustatic cyclicity, and regression skewed when driven by regional tectonics associated with perched basin tectonics.

We quantitatively analyzed benthic foraminiferal assemblages in order to reveal biotic and paleoenvironmental trends in the Paleocene section of Gebel Aweina, Egypt, on the southern Tethyan shelf. The first correspondence axis ranks taxa along an empirically derived bathymetric gradient, with neritic taxa (e.g., Discorbis duwi and Haplophragmoides walteri) opposed to bathyal taxa (e.g., Nuttallides truempyi and Gavelinella beccariiformis). The estimated paleodepth, as reflected by the various assemblages, was mostly similar to 200 m, but varied between similar to 50 m (P3a, NP4) and similar to 300 m (P4, NP8). The resultant four relative sea-level cycles appear to be at least of regional extent and may in part be eustatically controlled. The second correspondence axis reflects trends in trophic and redox development. Low-food, high-oxygen conditions prevailed during Biochrons P1c-P3b (NP4-NP5) and late P4 (NP8), when assemblages were mostly dominated by Cibicidoides spp. Most oligotrophic conditions coincided with maximum paleodepth. Intermediate trophic levels were established during middle P4 (NP6) and early P5 (NP9). From the level of the latest Paleocene benthic extinction event (BEE; middle P5 and NP9) onwards until Biochron P6a (NP10), assemblages dominated by buliminids marked increased trophic levels and reduced ventilation, probably resulting from enhanced surface productivity. Enhanced surface productivity along the southern Tethyan margin started during Biochron P4, and, at least on some shelves, intensified after the BEE. Increasing productivity during the latest Paleocene contrasts with global trends. This may be expected Curing climatic warming and an expanding trophic resource continuum, leading to regionally intensified eutrophy and oligotrophy. High productivity through upwelling along the southern Tethyan provides support for GCM predictions of intense wind-stress in this region during the warm late to latest Paleocene. (C) 1998 Elsevier Science B.V. ispartof: Palaeogeography palaeoclimatology palaeoecology vol:137 issue:1 pages:79-101 status: published

Sea-level change is known to have influenced the evolution of marine life. It is examined here how faunal diversity and rates of taxic evolution are related to change in sea-level and stability of the sea-level cycles. Evolutionary metrics of Palaeogene larger foraminifera are calculated and stability of sea-level cycles are determined using number and average duration of third order cycles in each stratigraphic interval. Generic diversity and the rates of origin and extinction individually do not show one to one correspondence either with transgression-regression or with the stability of the sea-level cycles. The rate of extinction relative to the rate of origination, however, is found to be significantly affected by the stability of the sea-level cycles. The rate of extinction exceeds the rate of origin during the periods of low stability. Regression, assisted by unstable sealevel cycles and possibly sharp climatic deterioration caused extinction maxima of larger foraminifera in Late Eocene.

The Sopeira Basin is a small extensional basin with a conlinuous record of deposition from the upper Albian to the upper Turonian. In its early stages (upper Albian-middle Cenomanian) the sedimentation was controlled by local factors (extensional tectonics) with an influence of eustatic sea- level change. Later, during the upper Cenomanian-middle Turonian, the main sedimentary features are controlled mainly by global oceanic changes

Eustatic movements generate intricate patterns of coastal units. The resulting stratigraphyc architecture depends on eustasy, sediment supply and local tectonics. Tri-dimensional relations due to sea-level changes are interesting because they allow to reconstruct the existence and magnitude of eustatic changes, to understand the role of coastal deposits during the evolution of a basin margin, and to correlate depositional events

Eustatic movements generate intricate patterns of coastal units. The resulting stratigraphyc architecture depends on eustasy sediment supply and local tectonics. Tri-dimensional relatians due to sea-level changes are interesting because they allow to reconstruct the existence and magnitude of eustatic changes, to undersland the rofe of coastal deposits during the evolution of a basin margin, and to correlate depositional events.

The Sopeira Basin is a small extensional basin with a conlinuous record of deposition from the upper Albian to the upper Turonian. In its early stages (upper Albian-middle Cenomanian) the sedimentation was controlled by local factors (extensional tectonics) with an influence of eustatic sea- level change. Later, during the upper Cenomanian-middle Turonian, the main sedimentary features are controlled mainly by global oceanic changes

The evolution of a genetic unit of the Lias to the North of Velez-Rubio (External Zones of the Betic Cordilleras, South-east of Spain) has been studied. This unit, at its lower and upper boundaries, is limited by intra-Sinemurian and intra-Upper Carixian sedimentary breaks. Different factors that controlled the evolution of the basin during this period of time have been analysed; from this we can deduce that the role of tectonics could be dominant as contrasted with that of eustasy