South Of Crete Research Articles

Pore water signatures and gas hydrates occurrence in and around the Olimpi mud volcano field, south of Crete

Mud volcanoes in the Mediterranean Sea have been subject of scientific research since the 1970s and contributed to the understanding of these seafloor features and their role in the subduction budgets worldwide. Recently, the need to better characterize the connection of these mud volcanoes with the deeper lithologies of the accretionary prism and its implications led to expedition POS410 (2011) and SO278 (2020). During these expeditions, mud volcanoes which had been investigated in ODP Leg 160 (1996) were resampled and complemented with new sites along the Mediterranean Ridge accretionary complex. We present pore water data from six mud volcanoes and two brine pools in and around the Olimpi Mud Volcano Field (OMVF). The data highlight strong depletion in Cl (<200 mM), Na (∼200 mM), Mg and K (with concentrations ∼0 mM) and striking water isotope ratios (δ18O of +9.79‰ V-SMOW and δD of −26.33‰ V-SMOW), indicating dehydration of clay minerals at depth. At five locations, the interstitial waters are characterized by extremely high salinities (Cl > 5000 mM and Na >6500 mM), therefore drastically expanding the previous reports of highly saline pore waters in the OMVF. The measurements further reveal that Gelendzhik mud volcano, located in the western part of the OMVF along a major strike-slip fault, shows an unusual pore water downcore profile and its water isotopes signature differ strongly from the other structures (δ18O of +13.63‰ and δD of +1.83‰). Upon further investigation through XRF scans and hydrates stability calculations we tied the anomalous low salinity values of the Gelendzhik MV pore waters results from the presence of gas hydrates in the sediments. This is the first, indirect evidence of gas hydrates in the OMVF, several years after this hypothesis was formulated by De Lange and Brumsack (1998) and then quickly discarded.

Organic Geochemical Signatures of the Upper Miocene (Tortonian—Messinian) Sedimentary Succession Onshore Crete Island, Greece: Implications for Hydrocarbon Prospectivity

The definition of pre-Messinian source rocks in the eastern Mediterranean is of paramount importance for hydrocarbon exploration because of the ability of salt to act as a high-quality seal rock. This research evaluates the organic geochemical features of the Upper Miocene (Tortonian—Messinian) sedimentary succession onshore Crete Island, Greece. The study employs original (Messinian, Agios Myron Fm) and published (Tortonian, Viannos Fm, Skinias Fm, Moulia Fm, and Messinian Ploutis section) results from organic geochemical analyses of mudstone samples. One hundred and one samples were examined using standard organic geochemistry methodology (Rock-Eval II and VI-TOC) to define the origin, type, and degree of organic matter maturity. The data indicate that the studied samples have poor to fair gas-prone source rock potential. These possible source rock units have not experienced great temperatures during burial, and, thus, their organic matter is thermally immature. The sub-salt (Tortonian—Messinian) source rock units are likely to be of higher thermal maturity in the western and eastern south Cretan trenches because of tectonic subsidence and a thicker sedimentary overburden. Several traps can grow in these regions, associated with normal faults, rotated blocks and unconformities (both below and above the unconformities). This research provides a basis for the further evaluation of the hydrocarbon potential in Crete Island. It is an area that shares geological similarities with the surrounding regions that contain proven reserves and is of crucial economic and strategic importance.

The Messinian of Agios Myron (Crete, Greece): A key to better understanding of diatomite formation on Gavdos (south of Crete)

The Agios Myron section in the NE of the Heraklion Basin on central Crete exposes a pre-evaporitic Messinian sequence of 24 sedimentary cycles of deep-marine homogeneous and laminated marls (sapropels). Planktonic foraminiferal biostratigraphy and ash layers show that the 24 cycles in section Agios Myron correlate to cycles M79 to M102 in the well-studied and orbitally tuned Metochia section on Gavdos Island. The correlation of the cycle patterns in sections Agios Myron and Metochia not only provides tuned ages for sedimentary cycles, planktonic foraminiferal bioevents, and ash layers in Agios Myron, but also reveals that the diatomites in Metochia cycles M94-M102 have no equivalents at Agios Myron. The onset of diatomite formation on Gavdos at 6.72 Ma is shown to coincide with eutrophication and related to a restriction-imposed increase in salinity 20 kyr earlier at 6.74 Ma. Geographic differences in productivity and possibly also the better preservation potential of siliceous microfossils on the much deeper seafloor at the Metochia site are believed to explain why diatomites are present on Gavdos and absent in time-equivalent levels at Agios Myron.

The Rhetoric of Martyrdom: Remarks on a Painted Cycle of Saint Paraskevi’s Martyrdom in Venetian Crete

The vita of Saint Paraskevi the Roman is considered a fabrication, typical of the epic passions criticised by Hippolyte Delehaye for their lack of historical value. Rhetoric takes over facts, and, therefore, this vita is constituted exclusively of hagiographic topoi. The visual transposition of Saint Paraskevi’s martyrdom, popular in the late Middle Ages, in particular in Venetian Crete, provides evidence to the artists’ perception of the rhetorical devices used in panegyrics. This can be observed in the painted narrative cycles of Palaiologan monuments, not only in the most prestigious foundations linked to the imperial capital and the well-read elites, but also in more modest programmes, such as the short cycle of Saint Paraskevi’s martyrdom painted by Michael Veneris in the village church of Melampes, in the south of Crete c. 1320. Four episodes are displayed below a Christological cycle: Paraskevi’s trial is followed by three different scenes of ordeal: she is burnt with torches, then plunged into a cauldron and into a burning furnace. The unusual structure of this cycle, which includes two uncommon episodes, echoes the cumulative effect of ekphrasis, as well as the vividness that this device brings to every episode. Additionally, a comparison is established between the saint and Christ, a process that owes much to synkrisis, enabled by the juxtaposition of the two painted cycles. However, in the Melampes cycle, the image goes beyond the text, as the painter seems to suggest an exegetic reading of the saint’s martyrdom. The theme of light and fire, present in three of the four episodes, connects Paraskevi’s deeds to the words of Christ, highlighting the salvific content of martyrdom in an appeal to the viewer’s spiritual elevation.

Ecological Restoration Plasters and Mineral Pigments Designed with Raw Material from the Island of Gavdos

Gavdos is an island of ca. 34 km2 located to the south of Crete, Greece, with a local landscape rich in clay material of remarkable diversity in colour and quality. The limited natural and human-made resources are persistently recycled, forming the built structures of the island and determining the island’s sustainable local tradition. In the framework of this research, areas with clay soil were identified through a geological survey and testimonies of local inhabitants. The studied clay samples were characterized with mineralogical and physicochemical analyses. Two out of ten samples with a clay content higher than 50%, after low-temperature thermal treatment (600 °C and 700 °C), functioned as pozzolanic additives enhancing the performance in resistance to salt decay and plasticity of lime mortars. Seven raw clay samples were used as pigments in lime-based colours and their performance and durability, as assessed with the appropriate laboratory analyses, revealed the existence of stable mineral pigments under UV and visible light irradiation. There is great potential in the exploitation of local raw material from the island of Gavdos for the restoration of the traditional building stock on the island in terms of resource efficiency, environmental impact and preservation of the local identity.

Mesozooplankton community structure in the Eastern Mediterranean Sea

Abstract Mesozooplankton composition including functional groups in relation to hydrological features is studied in the oligotrophic pelagic ecosystem of the eastern Mediterranean Sea. Combining classic/standard microscopy and advanced digital imaging approach copepod growth rates, ingestion and production rates were estimated using allometric relationships. For this purpose, mesozooplankton samples were taken in the epipelagic zone (0–200 m) in June 2016, over a grid of 16 stations in the Cretan Sea, the Cretan Passage and the eastern and western Cretan Straits including one station in the Mirtoan Sea. The sampling area is influenced by the presence of the permanent Rhodes Cyclonic Gyre east of Crete and a series of smaller permanent or recurrent gyres south of Crete that influence the anti-estuarine pathway of the Atlantic Water from the Ionian Sea towards the Levantine Basin at surface and subsurface layers. Mesozooplankton abundance exhibited almost similar values (mean value 312 ind m−3 ± 100 SD) among transects with a higher value at the western Straits (up to 562 ind m−3). Copepods were the dominant group at all stations with almost the same relative contributions among stations (76%) but slightly higher values in the Cretan Passage. The contribution of copepod functional groups in the mesozooplankton community is also highlighted. The importance of small sized copepods was underlined by small ambush feeding carnivores, prevailing at all stations and demonstrating a high degree of opportunistic feeding of copepods in these ultra-oligotrophic waters, with chlorophyll a ranging from 0.05 to 0.20 μg L−1. Copepod vital rates (production, ingestion and respiration) estimated by a growth rate model were generally low, with higher values in the Cretan Sea.

Exceptionally preserved remains of Munidopsis ariadne Macpherson, 2011 (Galatheoidea) in Upper Pliocene fissure-filling micrites at Cape Milazzo (northeastern Sicily, Italy)

During the Late Pliocene, the Milazzo Peninsula (northeastern Sicily, Italy) experienced extensional tectonics, which may have led to fractures that were filled by pink-coloured micrite. Carapace remains of the galatheoid Munidopsis ariadne and chelae of a paguroid (Diogenes sp.) were found to be preserved three-dimensionally within these fractures. Until now, Munidopsis ariadne was known from extant material from south of Crete (Mediterranean) at depths in excess of 2,000 metres.

Analysis of gravity disturbance for boundary structures in the Aegean Sea and Western Anatolia

Western Anatolia has been shaped N–S-trending extensional tectonic regime and W-E trending horst, grabens and active faults due to the collision of Africa, Arabian and Eurasia plates. The borders of the Aegean Sea tectonic is limited between eastern of Greece, western of Anatolia and Hellenic subduction zone in the south of Crete. To evaluate these tectonic elements gravity disturbance data of the Aegean Sea and Western Anatolia was used in this study. It is thought that the gravity disturbance data reflects the tectonic elements and discontinuities way better than gravity anomaly due to the calculation from the difference between gravity and normal gravity at the same point so thus the tensors and invariants of the study area were calculated and the power spectrum method was applied to the gravity disturbance data. Various boundary analysis methods were applied to the gravity disturbance data to compare the discontinuities obtained from the tensors both theoretical and case study. These methods were tested initially on theoretical data. Within the scope of the theoretical study, a single model and three bodies model were taken into consideration. When the results are examined, it is observed that the Tzz tensor component gives very clear information about the location of the structure. Likewise, when the Txx, Tyy components and invariant results are examined, the vertical and horizontal boundaries were successfully obtained. In addition, the mean depths of these structures were determined using the power spectrum method. In the case application stage, the gravity disturbance data obtained from the Earth Gravitational Model of the eastern of the Aegean Sea and western of Anatolia were evaluated. The tensor and invariants of this gravity disturbance data were first calculated. New possible discontinuities have been identified in the tensors and some of the obtained discontinuities were clarified in their previous discussions. Also, the mean depths of the possible structures were calculated by the power spectrum method at four profiles taken from gravity disturbance data. These depth values are consistent with the depth values of the structural discontinuities obtained from previous studies. Finally, the upward continuation was applied to Tyy, Tyz and Tzz tensors up to 20 km. The positive anomaly values in Tyz and Tzz components and negative anomaly values in Tyy component are consistent with the Western Anatolia Transfer Zone. The structural differences between the eastern and the western of Western Anatolia are noteworthy in the upward continued results of the tensors. In addition, the positive and negative anomalies are notable in areas where the big earthquakes occurred in the last 3 years in the Tyz invariants.

Contemporary crustal stress of the Greek region deduced from earthquake focal mechanisms

A massive dataset of over 1900 focal mechanisms of crustal earthquakes with M ≥ 3.5 in the Greek region was employed to resolve the contemporary stress-field using a damped least-squares inversion. The results are in good agreement with the strain-rate field of the Global Strain Rate Model, which was used as reference, both in terms of their principal axes orientations and expected faulting styles. Dual stress-states were identified using the Multiple Inverse Method in regions delineated by joining neighboring Area Sources of the European Seismic Hazard Model 2013 (ESHM13). North-western Greece is mostly affected by transpressional tectonics characterized by NE-SW contraction. Northern/central Greece and the Corinth Rift are dominated by E-W normal faulting, with secondary oblique-normal to strike-slip faulting at the western margin of the latter. North and central Aegean are mainly governed by transtensional regime, characterized by stable N-S extension.The stress-tensor was found to be compatible with the Fault Sources (FS) of ESHM13, in terms of orientation and expected faulting type. Differences were observed in regions of low strain-rate, such as the Southern Aegean, where left-lateral, E-W strike-slip instead of normal faulting was inferred. Discrepancies in areas with strong local heterogeneities were highlighted by anomalies in the stress-ratio, Φ, indicating transtensional regime in the pull-apart basins of Western Greece and transpressional tectonics in north-western Greece and south of Crete. The latter is characterized by stable N-S contraction, SW-NE sinistral strike-slip and E-W reverse faulting in the vicinity of the subduction zone. A low Φ, E-W oriented zone was identified along the active volcanic arc, where a remarkable 90° rotation occurs in the stress field. This rotation is related to the transition from E-W (in the north) to N-S (in the south) normal faulting in Peloponnese and Dodecanese Islands, as well as rearrangement from dextral to sinistral SW-NE strike-slip faulting in North and South Aegean, respectively.

TECTONO-SEDIMENTARY EVOLUTION AND RATES OF TECTONIC UPLIFT OF THE SFAKIA COASTAL ZONE, SOUTHWESTERN CRETE

Sfakia lies within a narrow coastal zone at the southwestern foothills of the Lefka Ori Mt. Here a segment of the South Cretan margin is preserved onshore, a structure that represents a neotectonic structure with continuous activity since the Upper Miocene. This segment is characterized by a steep, E-W striking and south facing morphological escarpment that constitutes numerous E-W and ESE-WNW striking normal faults. Since the Late Miocene, marine sequences of Tortonian, Early Pliocene and Lower Pleistocene age were deposited along the coastal zone. Since the Middle Pleistocene multiple, coalescent alluvial fans covered both the alpine basement and the marine sediments. Fault-kinematic- and stratigraphie data combined with recently published palaeobathymetry reconstructions allow us to make relable estimates of both the uplift rates of fault blocks in the study area and the period that the faults that demarcate them were active. The results show that the study area is experiencing uplift already since the Middle Pliocene and that the uplift rates of the mountainous parts are higher than those of the coastal zone. The general uplift of the coastal zone seems to be controlled by offshore normal faults, south of Sfakia

AUTOMATIC IDENTIFICATION OF THE GEOMORPHOLOGIC AND MORPHOTECTONIC FEATURES OF THE SOUTH CRETAN MARGIN, USING OBJECT BASED IMAGE ANALYSIS

This paper is focused on the study of the South Cretan Margin, from a Digital Seabed Elevation Model, by employing Object Based Image Analysis. The goal is the automatic extraction of geomorphological and morphotectonic features based on morphological criteria and topological relations. A Digital Seabed Elevation Model of 150x150 meters resolution was employed. At first, slope, curvature, planform curvature, profile curvature and Topographic Position Index were derived from this DSEM. Five different layers of segmentation were created in order to extract the final geomorphological classes, Ptolemy trough, intraslope basins, main basins, small basins, continental shelf, plains, continental slope, escarpments, canyons, spurs, discontinuities, fault like and fault surface. The results were evaluated quantitatively, through the established indices Completeness, Correctness and Overall Quality. For computing these indices, it was necessary to digitize the boundaries of the objects derived by photo-interpretation. Then, the computation of the above indices, took place by comparing the results of digitized photo-interpretation boundaries, to the extracted feature boundaries through OBIA analysis (in shapefile). It is worth noting that, the results of the evaluation are quite satisfactory. Thus, the developed OBIA method is considered successful.

Possibility of Zeroing CO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; Emissions Due to Energy Use in Gavdos Island, Greece

The possibility of transforming Gavdos Island located south of Crete, Greece to a 100% renewable energies island has been investigated. Gavdos Island has few inhabitants but it hosts a large number of tourists during the summer. Due to the small size of the island the use of vehicles is limited. It has abundant local energy resources, mainly solar and wind energy, which are currently underutilized. Electricity is locally generated with diesel oil and its electric grid is not interconnected with the grid of Crete. Energy demand in the island has been estimated as well as the availability of various renewable energy resources. The most reliable and cost effective of them, including solar thermal, solar and wind power, solid biomass burning and high efficiency heat pumps have been indicated for achieving a 100% renewable island. Electric vehicles must also replace conventional vehicles in order to zero carbon emissions in transport. Since the power grid in the island is isolated, electricity storage is required and it could be obtained either with electric batteries or with a small hydro-pump storage system. The nominal power of the required solar-PV system for covering all the electricity needs in Gavdos island has been estimated at 848 KWp and the required electricity storage capacity was at 19.2 MWh.

First preliminary results for the absolute calibration of the Chinese HY-2 altimetric mission using the CRS1 calibration facilities in West Crete, Greece

In this work, absolute calibration of the Chinese HY-2 satellite altimetry mission is carried out, employing Pass No. 280 and the calibration facility, CRS1, located in the Southwest end of the island of Crete, Greece. Satellite Pass No. 280 is descending and follows a ground track almost parallel to the west coast of Crete. It comes close to the coast, at a distance of about 9km from the CRS1 calibration site, and finally goes away south of Crete. The HY-2 sensor geophysical data records (S-GDR) have been incorporated into the calibration procedures and processing has taken place for cycles No. 54–62, at 20Hz data rate. Some peculiarities in the HY-2 satellite altimeter data, as delivered and depicted in the I-GDR and S-GDR data, have also been noticed. All calibration results have been determined using a regional, precise and detailed geoid, along with a good knowledge of local ocean circulation and site characteristics and a well-defined sea-surface calibration methodology.The first preliminary results for the HY-2 altimeter calibration have shown that the initial cycles, up to No. 51, display an erratic behavior. After those cycles, the altimeter range bias values seem to be stable and reach a value of B=−45.6cm±4.4cm, when applying the net instrument corrections as provided in the GDR. If the relativistic effects of the satellite clocks are properly applied for the net instrument corrections, then the altimeter range bias goes down to B=−27cm±3cm. Also, preliminary cross-over analysis with the SARAL/AliKa and Jason-2 satellites show a bias of B=−23cm, and B=−28.5cm, respectively. The performance of the HY-2 on-board radiometer has also been examined in terms of the wet troposphere corrections and shows a mean difference of −1cm±0.1cm with respect to in-situ GNSS-derived corrections. Finally, the ionosphere path corrections of the HY-2 satellite show a difference of +1cm±1.1cm, when compared against the GNSS-derived ionosphere values.

Wave climate of the Hellenic Seas obtained from a wave hindcast for the period 1960–2001

The wave climate of the Hellenic Seas and particularly the climate extremes are investigated by means of a 42-year (1960–2001) model hindcast. The wave model, implemented over the Mediterranean basin, is forced by high-resolution winds generated upon downscaling of the ERA40 reanalysis. It is shown that the quality of the hindcast is overall satisfactory; however, extreme wave heights in the Aegean Sea are consistently overestimated. Accordingly, corrections to the original data are applied. The results show that the highest mean wave conditions are located east and west of Crete Island where the northerly air flow exits the Aegean Sea. Extreme waves are the highest outside the Aegean Sea, mainly in the southern Ionian Sea and south of Crete. Nevertheless, high waves also develop around the exits of the Aegean Sea and N-NE of the Cyclades islands. Despite a milder extreme wave climate in the Aegean Sea due to short fetch distances, the mean wave height range is very similar to that of the Ionian Sea. Moreover, in summer, the two seas exhibit similar extreme wave height conditions with the highest extremes found around the exits of the Aegean Sea to the Levantine basin. Storms of a longer duration are also observed in the Aegean Sea. The analysis of long-term trends in the wave climate shows that mean and extreme wave climate as well as the average intensity of extreme events have decreased in the Hellenic Seas. Nevertheless, this decrease has not been monotonic. A turning point is located around year 1981 with the mean and extreme wave height mostly increasing before this year and decreasing afterwards.

Coccolithophore assemblages during the Holocene Climatic Optimum in the NE Mediterranean (Aegean and northern Levantine Seas, Greece): Paleoceanographic and paleoclimatic implications

Recent paleoceanographic findings suggest that during the Holocene, NE Mediterranean climate was less stable than previously thought. Several recently generated Aegean paleoceanographic records of sapropel S1 suggest that during the Holocene short-term potentially global cooling episodes, reflecting the N. Atlantic climatic fluctuations and possibly related to solar variability, are superimposed on the underlying regional subtropical/tropical control on the hydrography and ecosystems. Detailed quantitative analyses of coccolithophores have been performed on the deep sea deposits of the NE Mediterranean Sea; four gravity core records from North Aegean Sea (SL- 152), SE Aegean (NS-14, NS-18) and South Cretan continental Margin/northern Levantine Sea (HCMR 2/22) respectively, with a focus on the regional expression of sapropel S1 deposition. In all sites, higher values of Florisphaera profunda, Helicosphaera carteri, Braarudosphaera bigelowii and the increase of stratification S-index within sapropel intervals can be interpreted as the result of elevated marine production in the deep photic zone and enhanced inflow of fresh water input during the S1 period. The stratification S-index is significantly higher in the North Aegean, in respect to SE Aegean and the South Cretan Margin (SCM), reflecting increased coccolithophore productivity at the lower photic zone, being associated with a remarkably stratified water column. The concomitant increased presence of B. bigelowii indicates the prominent riverine input in the North Aegean basins and possible influx of Black Sea waters after ∼9.0 ka BP. Consequently, the increased stratification of the water column is linked to the significant freshening of the North Aegean surface waters, particularly during the early stages of the Holocene Climatic Optimum (S1a depositional interval). A series of cooling events detected towards the end of sapropelic conditions (∼7.2 ka BP) mostly in the North Aegean site, may be linked to outbursts of cold northerly air masses and relevant pulses in the deep-intermediate water ventilation that caused the enhancement of surface marine productivity and the temporary cessation of S1 at ∼ 8.0 ka BP. In contrast, in the SE Aegean and the northern Levantine Sea, the water column remains still warm and stratified, influenced by moderate fresh water input, for at least 1 more ky.

Influence of chemosynthetic ecosystems on nematode community structure and biomass in the deep eastern Mediterranean Sea

Abstract. Mud volcanoes are a~special type of cold seeps where life is based on chemoautotrophic processes. They are considered to be extreme environments and are characterized by unique megafaunal and macrofaunal communities. However, very few studies on mud volcanoes taking into account the smaller meiobenthic communities have been carried out. Two mud volcanoes were explored during the MEDECO (MEditerranean Deep-sea ECOsystems) cruise (2007) with the remotely operated vehicle (ROV) Victor-6000: Amsterdam, located south of Turkey between 1700 and 2000 m depth (Anaximander mud field); and Napoli, south of Crete, located along the Mediterranean Ridge at about 2000 m depth (Olimpi mud field). The major aim of this study was to describe distributional patterns of meiofaunal communities and nematode assemblages from different seep microhabitats. Meiofaunal taxa and nematode assemblages at both mud volcanoes differed significantly from other Mediterranean sites in terms of standing stocks, dominance and species diversity. Density and biomass values were significantly higher at the seep sites, particularly at Amsterdam. Patterns of nematode diversity, the dominant meiofaunal taxon, varied, displaying both very high or very low species richness and dominance, depending on the microhabitat studied. The periphery of the Lamellibrachia and bivalve shell microhabitats of Napoli exhibited the highest species richness, while the reduced sediments of Amsterdam yielded a species-poor nematode community dominated by two successful species, one belonging to the genus Aponema and the other to the genus Sabatieria. Analysis of β-diversity showed that microhabitat heterogeneity of mud volcanoes contributed substantially to the total nematode species richness in the eastern Mediterranean Sea. These observations indicate a strong influence of mud volcanoes and cold-seep ecosystems on the meiofaunal communities and nematode assemblages.

Late postglacial paleoenvironmental change in the northeastern Mediterranean region: Combined palynological and molecular biomarker evidence

Three gravity cores collected from the NE Mediterranean (NEMR) across a transect from the northern Aegean Sea (North Skyros basin) to the south Cretan margin (SCM), were investigated for pollen and terrestrial biomarkers derived from epicuticular waxes of vascular plants during the last ∼20 ky. Pollen data show diversified mixed temperate forest in the northern borderlands and enhanced Mediterranean vegetation in the southern areas, documenting an N–S climatic trend. Terrestrial plant biomarkers and their diagnostic geochemical indices exhibit latitudinal patterns which are interpreted in terms of the different delivery pathways (fluvial/runoff vs. atmospheric transport), resulting from the climate conditions during different periods. During the Late Glacial and early deglaciation periods (20–14 ka BP) relatively increased humidity (H-index) is recorded in the north Aegean Sea, while in the South drier climate was the limiting factor for vegetation development. During this interval, terrestrial n-alkanes showed increased accumulation rates, suggesting massive transport of terrestrial organic matter through runoffs and rivers, followed by weaker input after 14 ka BP. After ∼11 ka BP a major expansion of forest cover is evidenced in the NEMR, accompanied by a higher H-index because of the climatic amelioration. The forest vegetation exhibited regionally different characteristics, with cool temperate taxa being more abundant in the Aegean cores, while the SCM record is being featured by Mediterranean elements. At the onset of the Holocene and throughout the Holocene Climatic Optimum the delivery of terrestrial biomarkers increased and became more significant in the Aegean sites compared to the SCM site. Within the Holocene, the average chain length (ACL) of long chain n-alkanes exhibits lower values in the northern Aegean than in the southeastern Aegean and SCM, indicating the predominance of warmer species southwards. Finally, the H-index records a conspicuous humidity increase between 5.4 and 4.3 ka BP in the south Aegean that coincides with an increase in the terrestrial biomarker supply and the deposition of a distinct sapropel-like layer, SMH (Sapropel Mid Holocene). Similar trends in T (temperature) and H indices are slightly delayed and attenuated in the northern Aegean and are accompanied by an increase in the ACL index. A noticeable increase in the accumulation rates (ARs) of terrestrial biomarkers and the HPA index values during this period are clearly recorded in all three cores, indicative of enhanced terrigenous inputs of organic matter along with higher in-situ preservation.

Drivers of deep Mediterranean megabenthos communities along longitudinal and bathymetric gradients

The Mediterranean deep sea, being isothermal and longitudinally trophic-graded, is an optimal natural benchmark to test for macro-ecological patterns of species distribution. The rel- evance of environmentbiota interactions on deep-sea megafauna in the Mediterranean Sea, a matter still neglected, is addressed here along longitudinal and bathymetric axes. Benthic and nektobenthic megafauna were collected in the 3 basins of the Mediterranean: the western (Cata- lan Sea and southern Balearic), central (western Ionian) and eastern (south of Crete) basins, with an otter-trawl Maireta system and an Agassiz dredge between 1200 and 4000 m depth. Simulta- neously, environmental data were collected on surface production, near-bottom physical parame- ters, sediment grain size and carbon content. Megafaunal biomass was higher in the Catalan Sea, decreasing eastward and with depth. Species diversity and evenness were relatively constant in the western and central Mediterranean at all depths, whereas these indices decreased with depth in the eastern Mediterranean. β-diversity analyses indicated a high species turnover between areas. The 3 basins presented significantly different environmental conditions. Sediment particu- late organic carbon, surface fluorescence and sediment grain size were the 3 environmental vari- ables that best explained the distribution of megabenthos along the longitudinal Mediterranean axis. These results show that the food supply, from either the surface or from the adjacent deep- sea floor, is critical in regulating the biodiversity of deep-sea Mediterranean megafauna and that this diversity is pooled region-wide. The heterogeneity of resources may be essential in maintaining these high levels of local and regional diversity.

A new squat lobster of the genus &lt;i&gt;Munidopsis&lt;/i&gt; (Crustacea: Decapoda: Munidopsidae) from the Mediterranean Sea

A new species of Munidopsis Whiteaves, 1874 is reported from the south of Crete, at 2046-2104 m, in the eastern Mediterranean Sea. The species ( M. ariadne ) is morphologically closely related to M. maunga Schnabel and Bruce, 2006, from New Zealand. The species is also close to M. polymorpha Koelbel, 1892, from Lanzarote, Canary Islands, and M. talismani A. Milne Edwards and Bouvier, 1894, from the NW Africa. The new species is described and illustrated and a diagnosis along with full illustration is provided for the latter 2 species.

Newly Excavated Artifacts from Hagios Charalambos, Crete, with Egyptian Connections

The Minoan ossuary at Hagios Charalambos is located in the upland plain of Lasithi in Central Crete. This article discusses eight items with Egyptian connections discovered in the excavations of the site in 2002 and 2003. Two pendants carved from hippopotamus ivory in the form of apes belong to classes already known from Minoan Crete. Six clay examples of the sistrum add to our knowledge of this musical instrument on Crete as only a single MM IA sistrum was known previously from this island. The artifacts increase the very small corpus of “Egyptianizing” objects known from MM IA Crete, a period that is contemporary with the beginning of the Middle Kingdom. They point to a complex trade network reaching Cretan ports on both the south and the north coasts that was already present. These objects help document the distribution of exotic items with overseas connections to the interior of the Minoan island, well away from any coastal seaport or important population center. They also underscore the ambiguous nature of the connections between Minoan Crete and the East Mediterranean at this period when one cannot be sure if the overseas connections are direct or indirect. Within Crete, however, the distribution of hippopotamus ivory and objects made from it suggests that this trade from overseas is with South Cretan ports rather than North Cretan ports, because the distribution is densest in the Mesara and gradually diminishes away from this region.