Strombus Bubonius Research Articles

An overview of Upper Pleistocene coastal deposits on Mallorca island

This review paper delves into the geological history of Mallorca, focusing on the Middle to Late Pleistocene period and its impact on the landscape and climate of the island. The Quaternary, particularly, the Last Interglacial, represents a relatively short timeframe on the global chronological scale, yet it is notable for its climatic instability and complex alternation of glacial and interglacial phases, leading to fluctuations in sea levels. During the last interglacial, millennial-scale fluctuations, known as Dansgaard–Oeschger and Heinrich events, occurred. Aeolianites are thought to have formed during periods of sparse vegetation cover and abundant sediment availability from the sea bed or platform (Heinrich events), while colluvial deposits and paleosols are believed to represent periods of reduced sediment supply and enhanced pedogenesis (Dansgaard–Oeschger events). These different deposits reflect climatic shifts and sea-level changes, offering insights into the environmental history of the island. Fossil evidence, including Strombus bubonius (currently known as Thetystrombus lauts) or “Senegalese hosts,” reveals past warm climatic fluctuations, particularly during the Last Interglacial. Myotragus balearicus exemplifies evolutionary adaptation and isolation on the island, offering a unique perspective on its paleontological legacy. The integration of stratigraphic characteristics and literature research on Optically Stimulated Luminescence (OSL) dating techniques provides a comprehensive temporal framework, spanning from Marine Isotope Stage 6 (MIS 6) to Marine Isotope Stage 2 (MIS 2), enabling the precise dating of geological events and a stratigraphic correlation.

Last interglacial sea level high-stand deduced from well-preserved abrasive notches exposed on the Galilee coast of northern Israel

This study investigates the morphometry and structure of abrasive notches exposed along the tectonically-stable, micro-tidal Galilee coast, Israel, south-eastern Mediterranean, since they can serve as past sea-level indicators. The characteristics of the notches, height (H), vertex (D) – distance of maximum retreat point from cliff face, height of retreat point from the floor and roof (HF and HR, respectively), etc., were surveyed using LIDAR and a digital laser rangefinder, and elevations were measured using DGPS. Rock resistance was measured by Schmidt hammer tests, which show that the most developed and best preserved notches were formed within the more resistant host rocks of the Cenomanian chalk and the Pleistocene aeolianite sandstone.The elevations of the abrasive floors of the exposed notches indicated a sea level slightly higher than at present at the beginning of MIS5e, with an upper limit between +0.5 and +0.75m. The morphometry of the MIS5e notches, which are larger than modern notches in the study area, suggests mechanical erosion by broken waves, where an energetic wave-dominant sea batters a sheltered coastal cliff. Two sub-units of MIS5e (the Yasaf Mb.) were deposited within the notches: (a) a conglomerate containing the diagnostic fossil Strombus bubonius which was found on the notch floor, and (b) a younger bioclastic sandstone sub-unit which fills and covers parts of the notches. These unique field relationships link the formation of the notches to the beginning of MIS5e, indicating an erosive phase which parallels large-scale MIS5e sea level evidence, suggesting relatively long stand-stills at an elevation of about +1m. The early MIS5e erosive phase was followed by a depositional phase during the later stage of MIS5e.

Eastern Mediterranean sea levels through the last interglacial from a coastal-marine sequence in northern Israel

A last interglacial (Marine Isotope Stage, MIS5e) marine-coastal sequence has been identified along the Galilee coast of Israel, with the type section located at Rosh Hanikra (RH). The microtidal regime and tectonic stability, along with the detailed stratigraphy of the RH shore, make the study region ideally suited for determining relative sea level (RSL) through the MIS5e interval in the eastern Mediterranean. The sequence contains fossilized microtidal subunits at a few meters above the current sea level. Unfortunately, all fossils were found to be altered, so that U-Th datings cannot be considered to represent initial deposition. We contend that U-Th dating of Strombus bubonius shells (recrystallized to calcite) suffices to indicate a lower limit of ?110 ± 8 ka for the time sea level dropped below the RH sedimentary sequence. The RH-section comprises three main subunits of a previously determined member (the Yasaf Member): (a) a gravelly unit containing the diagnostic gastropod Strombus bubonius Lamarck (Persististrombus latus), which was deposited in the intertidal to super-tidal stormy zone; (b) Vermetidae reef domes indicating a shallow-water depositional environment; and (c) coarse to medium-sized, bioclastic sandstone, probably deposited in the shallow sub-tidal zone. The sequence overlies three abrasion platforms that are cut by tidal channels at elevations of +0.8 m, +2.6 m and +3.4 m, and which are filled with MIS5e sediments. We present a detailed study of the sequence, with emphasis on stratigraphic, sedimentological, and palaeontological characteristics that indicate sea-level changes. Although without precise absolute dating, the stratigraphic sequence of RH through MIS5e allows us to identify a time-series of RSL positions, using the elevations of three stratigraphic subunits. Reconstructed RSL values range from +1.0 m to +7 m (with uncertainly < 1 m), and most fall within a narrow range of +1.0 to +3.3 m. Toward the end of MIS5e, RSL exceeded about +7 m. Glacial isostatic adjustment (GIA) modelling using multiple ice histories suggests that GIA corrections range between about ?1.8 m and +5.4 m. This implies that global mean sea level resided between ?0.8 m and +8.7 m during most of MIS5e. The absolute GIA correction would not be constant through the interglacial, and reduces to a range of ?1.2 m to+ 2.4 m towards the end of the interglacial.

A review of the MIS 5e highstand deposits from Santa Maria Island (Azores, NE Atlantic): palaeobiodiversity, palaeoecology and palaeobiogeography

The privileged location of Santa Maria Island (Azores archipelago) in the middle of the North Atlantic makes the fossiliferous outcrops on this island of utmost importance to gain a better understanding of how coeval living communities relate to the broader evolutionary and biogeographic history of the Atlantic basin during the late Neogene and the Quaternary. Here we focus on this island's MIS 5e fossil record, offering a comprehensive review on the palaeobiodiversity, palaeoecology and palaeobiogeography of the biota living in the mid North Atlantic during this interglacial. Several studies in oceanic islands stress the huge impact of sea level changes on insular communities. Pleistocene sea-level changes occur during the short-time events known as “Terminations” (associated to glacial/interglacial shifts) as well as with the onset of glaciations (associated to interglacial/glacial shifts). Both are responsible for extinctions and local disappearance of species, bottleneck effects and formation of new species, resulting in community structure changes. This work increases the number of fossil marine taxa reported from the Last Interglacial deposits of Santa Maria to 143 species. All the 19 new records are molluscs (13 gastropods and 6 bivalves), thus increasing the number of fossil molluscs to 136 species. Although thermophilic members of the “Senegalese” tropical fauna were found in these deposits, many of the most emblematic species (e.g., Persististrombus latus (=Strombus bubonius), Cymbula safiana, Harpa doris, Cardita senegalensis, Barbatia plicata, Ctena eburnea or Hyotissa hyotis) are absent, suggesting that they did not reach the Azores. Our results indicate that the main differences between the species composition of the MIS 5e and the present-day shallow-water Azorean communities are probably due to the dropping of sea surface temperature associated with the onset of the last glaciation, which had both direct and indirect effects on species ecology. A group of 21 thermophilic species was directly affected by the lower sea surface temperature, whereas a group of four sand-associated species was indirectly but similarly affected by the lowering of the sea level. Both groups have locally disappeared from the Azores. However, none of the extant endemic species found on the studied MIS 5e outcrops was apparently affected by the lowering SST. In contrast to the biogeographical relationships of the recent Azorean shallow marine molluscs, which are predominantly with the Mediterranean Region, Portugal and with the Madeira and Canary Islands archipelagos, the palaeobiogeographical relationships of the MIS 5e Azorean marine molluscs are mainly with Canaries and West Africa. Despite the general low similarity of the biogeographical relationships between the Azores and Cape Verde Archipelago, on both the recent and the MIS 5e analysis, this similarity is nevertheless higher for the MIS 5e mollusc assemblages, emphasizing the role of Cape Verde as an important source of warm-water species during the Last Interglacial.

The Middle–Upper Pleistocene Fronte Section (Taranto, Italy): An exceptionally preserved marine record of the Last Interglacial

The Fronte Section, a well-exposed stratigraphic succession from southern Italy (Taranto area), provides an uninterrupted marine sedimentary record of MIS 5e. At this location, a highly expanded (8.5m thick) stratigraphic succession, unconformably overlying Middle Pleistocene marine clay deposits, provides evidence for sea-level fluctuations during the Last Interglacial. An integrated study of Fronte Section, including facies analysis, detailed macrofaunal and meiofaunal characterization, and sequence stratigraphy, is presented. The occurrence of Persististrombus latus (=Strombus bubonius) and other warm-water indicators (“Senegalaise” – “Senegalian” – guests of Gignoux, 1913), together with the presence of the dinocyst Polysphaeridium zoharyi and ten U-series dates on Cladocora caespitosa samples, permit an unequivocal MIS 5e age assignment to the upper part of the study succession. Above a stratigraphic unconformity marked by the boring coastal-lagoonal bivalve Pholas dactylus, the MIS 5e succession displays a first transgressive suite of brackish to shallow-marine deposits. These latter include highly fossiliferous muds rich in C. caespitosa, overlain by a fossil-rich calcarenite, 2m-thick, yielding warm-water “Senegalian” mollusks. Above this prominent stratigraphic marker (regionally called panchina), which is interpreted to represent a short-lived phase of sea-level stillstand or gentle fall during MIS 5e, renewed transgression took place, leading to the accumulation of middle-outer shelf muds, about 5m thick. The maximum flooding zone is clearly identified on the basis of the turnaround from a deepening-up to a shallowing-up trend. The upper part of Fronte Section records a second fossil-rich, sublittoral calcarenite containing warm-water mollusks, which is interpreted to reflect the subsequent phase of sea-level highstand, likely correlative with the MIS 5e plateau.

Palaeogeographic reconstruction of northern Tyrrhenian coast using archaeological and geomorphological markers at Pianosa island (Italy)

This paper provides new data and interpretations on the relative sea level change occurred at Pianosa island (Italy) since the last ∼125 ka, where the recent relative sea level changes have not yet been adequately constrained, based on geomorphological and archaeological research of tectonic movements. The MIS 5.5 deposits are characterized by a 2 m thick sandstone, cropping out at a maximum altitude of 4 m a.s.l. containing Strombus bubonius, and are associated with an abrasion platforms carved by lithodome holes. These deposits, considered one of the best long term sea level markers, establish that Pianosa was a stable area since 125 ka. Archaeological remains provide evidence of sea level change for the last ∼8 ka. Particularly useful are some fishtanks and a quarry cut around 2 ka BP (Roman age). The measurements, compared with predicted sea level curves, have established that Pianosa has remained stable during the last millennia. Based on this assumption, palaeomorphology variations since Palaeolithic age for this portion of the Tuscan Archipelago are reconstructed.

Chronostratigraphic confirmation of MIS 5 age of a baymouth bar at Is Arenas (Cagliari, Italy)

In 2005, the National Geological Survey of Italy released the new sheet, 557 Cagliari (1:50.000 scale). A coastal barrier marine formation at Is Arenas (Cagliari, Sardinia, Italy), containing Strombus bubonius, was reassigned a Holocene age, in contradiction with extensive literature published over the past century indicating an MIS 5.5 age. In 2007, spurred by this controversy, a short note was published in Il Quaternario demonstrating the stratigraphic difficulties in attributing the age of this formation to the Holocene. Later, another paper signed by numerous Italian geologists was published in Il Quaternario criticizing the Holocene attribution. The tectonic consequences of assigning a Holocene age to these deposits are of great significance, as their elevation could only be explained by strong uplift over the past few thousand years. Such a tectonic setting would imply a radical change in the recent geodynamic history of Sardinia, which is considered to be among the most stable areas of the Mediterranean basin. This paper provides further geochronological data for a MIS 5 age for the deposits at Is Arenas. Electron Spin Resonance (ESR) analyses were performed on 4 fossil shells sampled along the fossil baymouth bar. The results established an MIS 5 age. The amino acid racemization (AAR) and U-series data that first determined a correlation with the last interglacial, Tyrrhenian age of this ancient shoreline is reviewed, with additional documentation provided by the fossil marker S. bubonius.

Deux cycles transgressifs tyrrhéniens dans les dépôts côtiers de la péninsule du Cap Bon, Tunisie

A sedimentological and fauna analysis of Quaternary deposits at two sites located on the south-eastern littoral of the Cap Bon peninsula (Tunisia) provides new details about sea-level changes. Two shallowing-upward sequences separated by an erosion surface occur above the present sea level at several locations along the south-eastern shoreline of Cap Bon peninsula. Each sequence has a distinctive sedimentology and fauna content. The older one is especially rich in quartz grains and lithic fragments and is associated with shallow marine fauna in the lower member which would indicate a high relative sea level. The younger sequence is dominated by carbonates such as pellets, oolithes and mollusk fragments. The fauna of its lower marine member is rich in “Senegalian fauna” such as the Strombus bubonius LAMARCK. This biomarker, revealed at other locations in Tunisia (e.g., Sahel region, Jorf and Jerba Island) and at many sites around the Mediterranean Basin (Spain, France, Italy, Greece, Lebanon, and Egypt), indicates warm sea water. Both units include paleosols, colluviums and dunal members indicating respectively a wet phase followed by a drier phase. The vertebrate fauna discovered in the dunal deposits of the carbonate unit provides more information on the development of a savannah occurring with trees in the Cap Bon land at the post-Tyrrhenian.

Radiometric dating (U/Th) of the lower marine terrace (MIS 5.5) west of Nice (French Riviera): Morphological and neotectonic quantitative implications

Measurements of U/Th disequilibrium by mass spectrometry with a plasma source were used for the dating of shells collected on the lower marine terrace to the west of Nice. The dates obtained (129 ± 30 ka) arranged with palaeoclimatic data indicate that this terrace corresponds to the MIS 5.5 (Tyrrhenian pro parte) and can be correlated with the level with Strombus bubonius located to the east of Nice. Thus, a profile of almost 70 km can be restored with precision from altimetric measurements of the deposits and from sedimentological indicators of the sea level. This profile passes from the tectonic foreland of Provence to the front of the Nice Alpine Range after skirting the Pliocene Var Basin. It thus crosses major structural limits. As expected, the deformation of the lower Tyrrhenian terrace consists of a west-to-east uplift with two boundaries: (1): the “Var Fault” located under the Pliocene Basin; and (2): the border fault of the Nice Range. On a regional scale, the uplift appears closely related to the Nice Range activity. It decreases to the east, in the Flyschs zone, then increases again up to the Apennines chain.

Further evidence for a relatively high sea level during the penultimate interglacial: open-system U-series ages from La Marina (Alicante, East Spain)

The elevation and timing of high sea stands during Oxygen Isotope Stage (OIS) 7 are not as well constrained as those of OIS 5e. Conflicting values are reported from Mediterranean coastlines, and fossil dating is inaccurate because of ubiquitous open U-series systems. New morphostratigraphic data from La Marina (eastern Spain) supported by open-system U-series coral ages shed light on the maximum sea level during OIS 7. Fossil corals (Cladocora caespitosa) underlying an OIS 5e marine unit yielded U-series ages from 178 ± 10 to 208 ± 11 ka (±2s; n=7) with an outlier at 240 ± 18 ka. Mean open-system limit ages of 170 ± 10 (minimum age after correction for 234Th -230Th uptake) and 237 ± 20 ka (maximum age after correction for 238U - 234U uptake) were calculated to have a probable age closer to the minimum value, for an assignment of OIS 7a or 7c. The occurrence of a warm-water “Senegalese” fauna (Strombus bubonius) in OIS5e and OIS 7 marine units confirms the arrival of tropical species to the Mediterranean before the last interglacial period. Morpho-sedimentological and neotectonic studies suggest that the maximum paleo-sea level during OIS 7c or 7a was a few meters below that of OIS 5e.

Elevation of the last interglacial highstand in Sicily (Italy): A benchmark of coastal tectonics

Well-preserved MIS 5.5 terraces in Sicily are identified primarily by the index fossil Strombus bubonius, and dated by amino acid racemization (AAR), electron spin resonance (ESR), Uranium/Thorium (U/Th) and thermo luminescence (TL) methods. This review of published data and new results for the island of Sicily and neighbouring small islands of Egadi, Ustica and Lampedusa identifies areas of rapid uplift in the east (up to +175 m, elevation above sea level), slower uplift in the north (+29 m), and relative stability in the northwest (+2/+18 m). In contrast, about 250 km of the southern coastline of Sicily does not appear to contain MIS 5.5 outcrops. In eastern Sicily, correlation of MIS 5.5 highstands is based on Strombus bubonius, discovered at +86 m, and correlated with the inner margin terrace at +110 m, In the Taormina area, a fossiliferous marine conglomerate on a terrace with an inner margin at +115 m occurs in an area with undated terrace morphology and elevation data. Based on ESR methodology applied to fossils sampled at +105 m in Taormina, we attribute this terrace to MIS 5, probably 5.5. This age allows us to constrain the date of one point along a very long coastline that is otherwise undated. A newly discovered fossil beach (between +7 and +9 m) at Cefalù (north-central Sicily) attributed to MIS 5.1/5.3 using AAR analysis, permits correlation of MIS 5.5 to a +29 m-high tidal notch geomorphologically related to a terrace at the same elevation. Cefalù lies in an important position between the uplifted coastline of northeastern Sicily, and the more stable coastline of western Sicily. This compilation of MIS 5.5 data for all of Sicily reflects the active tectonics of eastern Sicily in contrast to the rest of the island.

Découverte d'une faune de mammifères du Pléistocène supérieur dans la grotte d'El Geffel (cap Bon, Tunisie)

The Quaternary series outcropping in the Cap Bon area (North-East of Tunisia) is characterised by two types of facies. The lower one is rich in warm marine molluscs such as Strombus bubonius LAMARCK, which expanded during the transgressive Tyrrhenian period, along the south margin of the Mediterranean Sea and elsewhere around this marine basin. The upper facies is continental and rich in gastropoda such as Helix and Rumina. In the deposits of this upper facies, a cave rich in big mammalia remains is discovered. These fossils are attributed to six species, composed at least of 12 individuals of grazer big mammalia belonging to groups such as Equids, Rhinocerotids, Bovids, and Hystricids. All these species, attributed to Late Pleistocene period, could be adapted to large open biotopes and especially dry climate biotopes, where a savannah vegetal cover was developed. To cite this article: A. Chakroun et al., C. R. Palevol 4 (2005) .

Pleistocene raised marine terraces of the Spanish Mediterranean and Atlantic coasts: records of coastal uplift, sea-level highstands and climate changes

Detailed geological mapping, morphostratigraphic, palaeontological and geochronological (uranium-series) analyses were undertaken on the raised marine terraces and interbedded terrestrial deposits along the Spanish peninsular and insular Atlantic and Mediterranean coasts. Several sets of Pleistocene shallow-marine to coastal deposits exposed in a staircase arrangement are interpreted as being emplaced during sea-level highstands coeval with interglacials or interstadials correlating with marine Oxygen Isotopic Stages (OIS) 5a/5c, 5e, 7, 9/11 and older. Up to three highstands have been identified in deposits formed during OIS 5e. Close to the end of OIS 5e there is a record of sudden changes in sea-surface conditions and climate marked by the disappearance of a major proportion of the warm ‘Senegalese’ fauna, switches from oolitic to non-oolitic facies, and accumulation of boulder beaches. Dating of the coral Cladocora caespitosa, found in a layer that also contains Strombus bubonius, confirms the occurrence of warm fauna in the Mediterranean basin during OIS 7, as previously suggested by Hillaire-Marcel et al. (1986), Goy et al. (1986a,b), Zazo and Goy (1989). Also the occurrence of warm faunas in deposits corresponding to an older interglacial, probably OIS 9 or 11, in the Balearic Islands suggests similar oceanographic conditions (sea-surface temperature, assuming constant salinity) during the last interglacial and at least two interglacials of the Middle Pleistocene in the western Mediterranean.

U-series evidence for two high Last Interglacial sea levels in southeastern Tunisia

Pleistocene raised marine deposits in southeastern Tunisia consist of a siliciclastic unit that culminates at +3 m asl, overlain by a carbonate-rich unit with Strombus bubonius that culminates at +5 m asl. 234U/ 238U ratios on fossil Ostraea shells from both units are compatible with a marine origin from the uranium incorporated into the shells and show narrowly clustered 230Th-ages, respectively, between 147 and 110 ka and 141 and 100 ka. The two units were therefore developed during Marine Isotopic Substage 5e (MISs 5e, Last Interglacial). Their heights are comparable to those of contemporaneous marine deposits found in many tectonically stable areas of the world such as in the Bahamas and in Bermuda and can therefore be used as indicators of eustatic changes during the Last Interglacial. It is argued that on the basis of this evidence, the Last Interglacial was characterised by two eustatic maxima.

Le Pléistocène supérieur marin (Tyrrhénien) en Crète nord-orientale (Grèce) / The Marine Upper Pleistocene (Tyrrhenian) in north-eastern Crete (Greece)

Abstract Coastal regions in north-eastern Crete offer numerous outcrops of Tyrrhenian formations. Their study reveals sediments corresponding to three main high sea stands during the last interglacial with intercalations of aeolianite. The three transgressions are correlated with isotope stages 5.5 (125 ka), 5.3 (120 ka) and 5.1 (80 ka). Strombus bubonius Imk, the index fossil of the Tyrrhenian, is present in the two earlier deposits. During the marine episodes, rapid sea level variations are evidenced by vermetid coatings on more deep fades sediments and by notches in the underlying bedrock. The Tyrrhenian stratigraphy of Crete throws a new light on Tyrrhenian stratigraphy of the Peloponese where references to the Eutyrrhenian and Neotyrrhenian are frequent in the the literature. The outcrops attributed to the second show the same morphostratigraphic features as those of the second Cretan transgression and, consequently, can be attributed to the 5.3 isotope stage.

Lignes de rivage soulevées de Calabre méridionale : un enregistrement géomorphologique de variations climatiques rapides au cours des stades isotopiques 5c à 5a/Uplifted shorelines in southern Calabria: a geomorphic record of rapid climatic fluctuations from the 5c to 5a isotopic substages

Abstract On the southern coast of Calabria (southern Italy), in the Palazzo Garibaldi area, several quarries provide good exposures and an opportunity for very accurate characterization of a flight of wave-cut platforms separated by paleosea-cliffs among which one is less than 1 m high. Transgressive pebble-rich marine deposits give evidence of these abrasion platforms which truncate the foreset beds of the conglomeratic substrate. With the help of seven electronic high-resolution altimeters, five successive paleoshorelines were measured between elevation of 124 and 96 m. In the Nocella area, a Tyrrhenian shoreline, exhibiting Strombus bubonius and raised to 164 m, is attributed to stage 5e and is considered as being the shoreline that corresponds to the oldest hot fluctuation of this Interglacial, the age of which is 130 ka. In coastal areas of the Mediterranean sea for which there is no evidence for neotectonic activity, the corresponding paleosea-level is about +3 m high. It is deducted a 1.24 m/ka uplift rate. As the number and elevation of shorelines at Nocella and Palazzo Garibaldi are similar, one is led to behave that they have been uplifted by roughly equal amounts. An attempt at correlating the raised paleoshorelines of the Palazzo Garibaldi area with hot peaks of the GRIP curve leads to attribute the 116 m shoreline to the second climato-eustatic maximum of substage 5c (Dansgaard-Oeschgef 's IS 23 = 102 ka). The 96 m shoreline would be correlated with IS 22 (= 87 ka, substage 5a probably). Within the lag which separates these two shorelines, two others, which are respectively at 112 m and 107 m, could be attached to fluctuations or stands which are visible on declining limb of the eustatic curve between IS 23 and IS 22 interstages. Finally between 105 and 87 ka, five hot oscillations (or plateaus) are recorded by shorelines currently ranging between 120 and 96 m. Two shorelines can be correlated with main fluctuations of substage 5c and two others belong to substage 5b, separated by an only 2-3 ka interval. This implies rapid climatic changes.

Thermoluminescence dating tests of Pleistocene sediments from uplifted marine shorelines along the southwest coastline of the Calabrian Peninsula (southern Italy)

Abstract This paper presents TL age estimates of Pleistocene raised marine terraces from southern Calabria (southern Italy). It focuses on the dating of last interglacial shallow-marine sand deposits, including several Tyrrhenian key reference deposits whose stratigraphic assignment is based on biostratigraphic evidence (presence of a Strombus bubonius fauna) and geochronometric data (amino-acid data calibrated with U Th dates on coral). The TL age estimates are obtained on alkali feldspar coarse grains using their blue TL emission. They are in good agreement with the IR-OSL age estimates obtained on the same feldspar samples. Our feldspar TL method is tested on two Tyrrhenian key reference sites, Ravagnese and Bovetto, in the Reggio di Calabria area. Their measured TL age estimates (97 ± 11 ka and 100 ± 10 ka) are lower than their estimated geological age (i.e. Oxygen Isotope Substage 5e). The correction for long-term fading suggested by Mejdahl (1988), is tested on these two samples using a lifetime of 446 ka as estimated from both Calabrian and Miocene sand collected within the same area. This correction would yield preliminary TL ages (116 ± 13 ka and 116 ± 12 ka) that are in better agreement with the expected geological age. The application of our TL method to paleoshorelines lying below the Tyrrhenian reference shoreline of Ravagnese-Bovetto, yields stratigraphically consistent TL age estimates. The TL method is also applied to two supposedly pre-last interglacial paleoshorelines which are geomorphologically older than the Tyrrhenian reference shorelines. They remain however chronologically undifferentiated, both by the TL and the amino-acid methods. Finally, the preliminary feldspar TL results obtained on the Miocene and the Calabrian sand deposits (> 1 Ma), suggest that our feldspar TL method is limited, in the SW Calabrian area, to about 200 ka.

Transverse and linear dunes in an Upper Pleistocene marine sequence, Corinth Basin, Greece

ABSTRACTA range of large‐scale dunes of oolitic calcarenite composition are exposed in the Corinth Basin of central Greece. These transverse dunes and a very large linear dune (&gt; 15 m high) lie within an Upper Pleistocene, transgressive marine sequence. Tidal flow, accelerated by constriction through a narrow, fault‐bounded seaway, is interpreted to have generated the current velocities necessary to produce the dunes.Marine facies in the Upper Pleistocene sequence include beach to offshore conglomerates and sandstones with wave‐modified sedimentary structures and herringbone cross‐stratification. An offshore facies association comprises variably bioturbated siltstones and sandstones with a varied marine fauna that includes thermophile species such as scleractinian corals and Strombus bubonius. Oolitic sandstone facies also occur.Oolitic sands were apparently produced in shoal environments subject to tidal (and wave) action, and transported by dominant southerly currents over the southern part of the basin. Oolites accumulated in a linear dune 2.7 km long and 15–20 m high and in three‐dimensional transverse dunes up to 10 m high having a variety of compound and simple internal geometries. The isolated, WSW‐ENE‐trending linear form exhibits angle of repose sedimentary dips (up to 35°) of avalanche sets on its SE flank and sets typically with dips of 15–20° to the NW. Internal high‐angle discontinuities are developed in the SE‐dipping lee face. It is proposed that a dominant north‐to‐south flow crossed over the crest obliquely, resulting in both net erosional and depositional processes on the lee flank. A subordinate (?tidal) current may have locally and or periodically crossed the dune crest in a westwards direction. A string of transverse dunes, which were located adjacent to a fault/marine terrace scarp, is interpreted to have originally coalesced to form the linear dune.The distribution of transverse and linear dunes together with the palaeogeographical reconstruction suggest that a marine connection periodically existed across the Corinth Isthmus during the Late Pleistocene due to a combination of active faulting and glacio‐eustatic highstands of sea level.

Morphometric analysis and amino acid geochronology of uplifted shorelines in a tectonic region near reggio Calambria, South Italy

The tectonic coastline of the Calabrian Peninsula provides an opportunity to study the morphology and history of elevated marine shorelines. Near Capo dell'Armi, eleven shorelines are preserved between sea level and 256 m. With some correlation difficulties posed by the dissection of the area by intermittent streams, we are able to correlate several of the shorelines across the entire study area. With the support of correlations provided by amino acid geochronology, we have identified four shorelines dating from the last interglacial period (isotope stage 5); the oldest two both contain the Strombus bubonius fauna and are of indistinguishable early last interglacial ages (stage 5e, aminozone E, ca. 125 ka). The highest terrace VII is associated with a shoreline at 157 m and the lower with a shoreline around 125-105 m a.s.l. Of the two younger stage 5 without Strombus bubonius, the higher (V) lies at about 90–100 m and produces amino acid ratios slightly younger than, but statistically indistinguishable from those of aminozone E. However, the youngest last interglacial shoreline deposits (IV) have produced amino acid ratios correlated to late stage 5 (5a) elsewhere in the Mediterranean basin. Amino acid and geomorphic data have shown that uplift varies the study area from 0.85 to 1.03 m/ka and suggeststhat constant uplift along any one traverse is unlikely.

Editorial

This paper presents TL age estimates of Pleistocene raised marine terraces from southern Calabria (southern Italy). It focuses on the dating of last interglacial shallow-marine sand deposits, including several Tyrrhenian key reference deposits whose stratigraphic assignment is based on biostratigraphic evidence (presence of a Strombus bubonius fauna) and geochronometric data (amino-acid data calibrated with UTh dates on coral). The TL age estimates are obtained on alkali feldspar coarse grains using their blue TL emission. They are in good agreement with the IR-OSL age estimates obtained on the same feldspar samples. Our feldspar TL method is tested on two Tyrrhenian key reference sites, Ravagnese and Bovetto, in the Reggio di Calabria area. Their measured TL age estimates (97 ± 11 ka and 100 ± 10 ka) are lower than their estimated geological age (i.e. Oxygen Isotope Substage 5e). The correction for long-term fading suggested by Mejdahl (1988), is tested on these two samples using a lifetime of 446 ka as estimated from both Calabrian and Miocene sand collected within the same area. This correction would yield preliminary TL ages (116 ± 13 ka and 116 ± 12 ka) that are in better agreement with the expected geological age. The application of our TL method to paleoshorelines lying below the Tyrrhenian reference shoreline of Ravagnese-Bovetto, yields stratigraphically consistent TL age estimates. The TL method is also applied to two supposedly pre-last interglacial paleoshorelines which are geomorphologically older than the Tyrrhenian reference shorelines. They remain however chronologically undifferentiated, both by the TL and the amino-acid methods. Finally, the preliminary feldspar TL results obtained on the Miocene and the Calabrian sand deposits (> 1 Ma), suggest that our feldspar TL method is limited, in the SW Calabrian area, to about 200 ka.