George Syrides

Preliminary results about thestratigraphy and the palaeoenvironment of Mygdonia Basin, Macedonia, Greece

Abstract Mygdonia basin (Macedonia, Greece) was formed during early—middle Miocene and then it was filled by a series of Neogene Quaternary deposits, which were divided in two groups, Premygdonian and Mygdonian. Three different formations have been distinguished in Premygdonian Group, while eight mammalian and one molluskan fossiliferous sites have been found. Chrysavgi Fm is the oldest, dated to the end of middle Miocene. Gerakarou Fm, consisted mainly of red-beds, is dated to early Pleistocene (late Villafranchian). Platanochori Fm has been dated to the end of early Pleistocene (latest Villafranchian) and represents the transition from Premygdonian to Mygdonian Group. Since now no fossils have been found in Mygdonian Group, in order to give a precise dating. However, its deposition begun in the middle Pleistocene and it is still continued. During the end of middle Miocene the climatic conditions were dry with seasonal rainfalls. The early Pleistocene is characterized as a dry period, while an increase of wetness at the end of the early Pleistocene is obvious.

Contribution on the Holocene Reconstruction of Thessaloniki Coastal Plain, Greece

Abstract During the Holocene, the western part of the present-day Thessaloniki coastal plain (north-central Greece) was flooded by the rising sea level and formed a bay as a consequence of the last postglacial transgression. The rate of the sealevel rise subsequently decelerated, and this bay began to fill with sediments delivered by the Aliakmon and Axios, as well as by other smaller rivers. The palaeogeographic and palaeoenvironmental reconstruction of the Thessaloniki Plain was the focus of several studies published during the past century. Most of these studies are based on the interpretation of historical sources and support the assumption of a fast filling of the bay between the fifth century BC and the fifth century AD. In this work, we first present the results of the analysis of data collected from six boreholes recently drilled in the western part of the plain, up to the western bank of the Axios River. Our study was mainly based on sedimentological and palaeontological analyses and accelerator mass spectrometry and conventional radiocarbon dating of shells and peat. Second, we evaluate the results of this study, as well as of other geological studies, which permit the description of the large-scale stratigraphic pattern of the plain. Data were evaluated on the basis of a geographic information system, used for the first time in such type of work, and were supplemented and assessed with analysis of Landsat imagery. Based on this evidence, we propose a new, detailed palaeogeographic reconstruction for the evolution of the Thessaloniki Plain during the Late Holocene. This plain corresponded to a wide marine bay during the Neolithic times (6000 BP), and later it was characterised by a fast displacement of the shoreline, mainly during Late Bronze Age, Iron Age, and Classical–Archaic periods (2650–2300 BP). A slowing down of the progradation of the alluvial plain occurred during Roman times (2100–1600 BP), and the plain obtained its present-day topography during the second part of the 20th century.

A pliocene primate from Macedonia (Greece)

Abstract A cercopithecid mandible is described from the locality Megalo Emvolon in Macedonia (Greece). The main morphological characters of the mandible and teeth as well as the dimensions allow us to attribute this specimen to Dolichopithecus ruscinensis . The mandible is compared with known material from Europe. The similarity of the Megalo Emvolon specimen to the material from Perpignan indicates a late Ruscinian age (MN 15) for Megalo Emvolon. This age is also confirmed by the other faunal and stratigraphical data. Three different primate biozones in Macedonia are discussed: the Ouranopithecus biozone of the Vallesian, the Mesopithecus biozone of the Turolian and the Dolichopithecus biozone of the Ruscinian.

Yria (western Naxos island, Greece): Sea level changes in Upper Holocene and palaeogeographical reconstruction

The Saint Georgios coastal zone, located at the W coast of Naxos, the largest island of the Central Aegean Sea, was investigated in order to determine the palaeo-geography, sea level changes and their effect to the palaeo-environment of western Naxos island and to human activity. Detailed geomorphological mapping, study of micropaleontological and sedimentological characteristics and dating analyses of the Late Holocene of St. Georgios coastal zone were conducted. To obtain information about the Holocene stratigraphy under the recent alluvial cover, three boreholes followed the detailed geomorphological mapping. Microfaunal analysis took place and five samples of plants, shells, peat and charred material were also collected from several layers of the sedimentary sequence and were dated using AMS and conventional radiocarbon techniques providing temporal control of the sediments. The sea-land interactions during Upper Holocene, in relation to the eustatic sea level oscillations, as well as the geomorphologic observations and analysis on deposited sediments, aims to reveal the palaeo-geographic evolution of the landscape and its impact on the archaeological sites. Sea level rise along with sea-land interactions to the landscape evolution and the transgression of sea in 6144 BP have been verified.

Neogene mollusk faunas fromStrymon basin, Macedonia, Greece. First results for biochronology and palaeoenvironment

Abstract Several fossiliferous sites with mollusk faunas have been located in Strymon basin. The faunal characters of the so far determined fossils and the lithology of the fossiliferous sediments allow the distinction of two groups. A. Fossiliferous sites, indicating a shallow marine palaeoenvironment with clastic sedimentation linked with the proximity of a palaeocoast. These sites have been dated to Pliocene and can be correlated with an early Pliocene marine transgression. B. Fossiliferous sites with fine grained clastic sediments and indications of a complicated (shallow marine — brackish — lagoonal to lacustrine) palaeoenvironment. These sites include lenses of euryhaline marine fossils alternated with marine, brackish and fresh water faunas. The fossiliferous deposits of this group, possibly overlie those of group A and could be dated to Pliocene.

A multi-proxy approach to reconstructing sedimentary environments from the Sperchios delta, Greece

This paper presents an integrated approach to assess Holocene environmental changes in the Sperchios delta, Sperchios rift, central Greece. A multidisciplinary study was carried out applying established analytical methods as well as exploring new techniques to detect past environmental conditions in a fluvio-deltaic depositional system. A series of six deep boreholes, up to 50 m long, and four shallow cores, up to 6 m long, from across the delta plain, were studied in detail. Sedimentary facies were defined by changes in grain size and macro- and microfaunal composition. Variability in mineral magnetic composition documented by changes in bulk magnetic susceptibility (χ and χ77K/χ293K) and remanence parameters (S−300 and σARM/σSIRM ratios), as well as down-core elemental variations obtained by scanning micro-x-ray fluorescence (µ-XRF), provide constraints on the depositional changes related to the evolution of the Sperchios delta. Correlations between elemental data derived by µ-XRF analyses and grain size were also analyzed and used to further constrain the facies interpretation. Overall, these Holocene sediments reveal a transgressive–regressive succession overlying pre-transgressive terrestrial deposits of Late Pleistocene–Early Holocene age. Furthermore, 13 new 14C radiocarbon dates constrain the transgression rate to be ~3.5 m/yr for the Early Holocene and the regression rate to be ~1 m/yr for the Late Holocene. The Sperchios delta plain developed when the rate of sea-level rise decreased ~6000 cal. yr BP as it has been proposed for the broader area of Aegean Sea. This study demonstrates that the combination of techniques used here provides a powerful way to map out paleoenvironmental changes and thus the 3D stratigraphic architecture of Holocene sedimentary successions.

A new Early/Middle Miocene mammal locality from Macedonia, Greece

A new fossiliferous locality with macro- and micro-mammals was found near the village of Agios Antonios, about 26 km southeast of Thessaloniki, Macedonia, Greece. The fossils are recovered from the fissure fillings of the karstified Mesozoic limestones of the basement. The fissures were filled in and covered by the clastic sediments of Antonios Fm, representing the first Neogene deposits of the Axios-Thermaikos Neogene palaeobasin. The age of the fauna indicates a time span from the end of the Early Miocene to the beginning of the Middle Miocene (upper part of MN 4 to lower part of MN 5). The deposition of Antonios Fm must have started during or a little earlier than the end of the Early Miocene, and consequently the Neogene Axios-Thermaikos palaeobasin was created during this time or a little earlier.

The Canal of Xerxes: summary of investigations 1991–2001

This paper summarizes the results of the earlier phase (1991–8) of geoarchaeological investigations at the Canal of Xerxes in northern Greece and then presents the findings of recent work. Through the combination of geophysical survey and analysis of sediments obtained from bore holes drilled along the supposed course of the canal it was established in 1996 that at least in the central sector of the 2 km wide isthmus there was indeed a deeply buried trench-like structure, c. 30 m wide. This is most likely to have been a canal that would have had a depth of water of up to 3 m. The recent work has explored first the situation at the southern end of the canal where one ancient writer claimed that the terrain would only have allowed the construction of a slipway (diolkos). However, seismic survey and sedimentological analysis of cores in that area found no obstacle to the digging of a canal. Second, the results of seismic survey (supported by the evidence of satellite imagery) at the northern end of the canal have suggested that its course was more easterly than that proposed earlier on the basis of the line of present-day lowest ground. In sum, all the indications are that there was a canal across the Athos peninsula and not a diolkos, and that the canals features conform to those outlined by Herodotus in his description of the structure built by Xerxes to allow the Persian fleet into the Aegean for the invasion of Greece in 480 BC.

Exploration of the Canal of Xerxes, Northern Greece: the role of geophysical and other techniques

The Canal reputedly built on the orders of the Persian King Xerxes across a narrow isthmus in northern Greece to allow his fleet access into the Aegean in advance of the Persian invasion of Greece in the early fifth century BC must have been a remarkable engineering operation for its time. Yet apart from a depression in the central sector of the isthmus, almost nothing of this canal is visible today, nor are there visible remains of building structures and harbour installations; what information there is about it comes from accounts by ancient writers, notably Herodotus, and nineteenth century travellers. This paper describes the results of a large programme of survey aimed at detecting this putative, now buried structure and ascertaining whether or not it was a canal across the full width (2 km) of the isthmus. Following a detailed topographic survey, resistivity soundings and ground-penetrating radar were carried out principally in the central sector of the canal; the latter detected successive infillings of the canal but neither its original sides nor its bottom. Seismic refraction and reflection measurements, on the other hand, provided decisive evidence for the canals existence in the central sector, with strong support coming from the analysis of sediment cores: its depth there is 14–15 m below the present ground surface, with top and bottom widths of 25–35 and at most 20 m respectively. The canals northerly course has been defined but less confidently, whereas to the south the picture still appears incomplete. The canal may indeed have been built across the full 2 km, but the alternative hypothesis that it connected with the sea at only one end and that there was a (short) slipway at the other end cannot be dismissed. Whichever model is correct, a crucial finding from the sediment analysis is that the lifetime of the canal was short. Copyright

The canal of Xerxes: investigations in 1993-1994

The paper describes the continuation in 1993–4 of the investigation into the Canal of Xerxes in the Chalkidiki, N. Greece. Effort was concentrated in the central sector of the isthmus, where geophysical survey using seismic methods revealed a channel-like structure some 14–15 m below the present ground level. Encouraging support for the hypothesis that this structure is a canal came from the analysis of cores from two boreholes in the central sector: there was a marked discontinuity in the sediments at a depth of c .14.6 m. Radiocarbon dates of some sediments from these boreholes provided useful ancillary information.