A synthesis of the circulation and hydrography of the South Aegean Sea and the Straits of the Cretan Arc (March 1994–January 1995)

A multidisciplinary study was conducted in order to investigate the environmental factors affecting the planktonic foraminiferal and pteropod communities of the south Aegean Sea. Aspects of the Late Quaternary paleoceanographic evolution were revealed by means of quantitative analyses of planktonic foraminiferal and pteropod assemblages (including multivariate statistical approach; principal component analysis (PCA)), the oxygen (δ18O) and carbon (δ13C) isotopic composition of planktonic foraminifera and related paleoceanographic (planktonic paleoclimatic curve (PPC), productivity (E-index), stratification (S-index), seasonality) indices, extracted by the gravity core KIM-2A derived from the submarine area between Kimolos and Sifnos islands. Focusing on the last ~21 calibrated thousands of years before present (ka BP), cold and eutrophicated conditions were identified during the Late Glacial period (21.1–15.7 ka BP) and were followed by warmer and wetter conditions during the deglaciation phase. The beginning of the Holocene was marked by a climatic amelioration and increased seasonality. The more pronounced environmental changes were identified during the deposition of the sapropel sublayers S1a (9.4–7.7 ka BP) and S1b (6.9–6.4 ka BP), with extremely warm and stratified conditions. Pteropod fauna during the sapropel deposition were recorded for the first time in the south Aegean Sea, suggesting arid conditions towards the end of S1a. Besides sea surface temperature (SST), which shows the highest explanatory power for the distribution of the analyzed fauna, water column stratification, primary productivity, and seasonality also control their communities during the Late Quaternary.

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Emplacement of the Miocene west Naxos pluton (Aegean Sea, Greece): a structural study

Geological Magazine ◽

10.1017/s0016756802007094 ◽

2003 ◽

Vol 140 (1) ◽

pp. 45-61 ◽

Cited By ~ 23

Author(s):

IOANNIS K. KOUKOUVELAS ◽

SOTIRIOS KOKKALAS

Keyword(s):

Aegean Sea ◽

Biotite Granite ◽

Distribution Analysis ◽

Block Rotation ◽

The South ◽

Mafic Enclaves ◽

The North ◽

Divergent Flow ◽

Regional Deformation ◽

Fry Method

Synmagmatic and solid-state structures within the Naxos pluton and its rim may provide insight into the interplay between plutonism and regional deformation at upper-crustal level. Within the hornblende–biotite granite of western Naxos, synmagmatic foliations display two distinct patterns, onion-skin in the north and tangential to the rim in the south. The two areas are separated by the NE-trending Glinadon fault. Deformed mafic enclaves in the pluton are prolate, with their long axes parallel to the synmagmatic lineation. In contrast, phenocryst distribution analysis, using the Fry method, defines an apparent oblate strain with a horizontal stretching lineation. Planar markers within the pluton progressively steepen through the vertical at the east pluton border. Several lines of evidence, such as dykes intruding axial areas of rim-parallel folds, foliated or folded aplite veins, folds and spaced cleavage in the mollase, and inverted stratigraphy, suggest pluton emplacement and deformation during transpressional deformation. A northward divergent flow regime with magma spreading out mainly from the Naxos fault, and the deflection of both the synmagmatic foliation pattern and the flow lines at the Glinadon fault, suggest that the NE–SW- and N–S-trending faults were active during pluton formation. In the south the pluton has grown by the expansion of dykes occupying P-shear positions with respect with the Naxos fault; in the north a piecemeal block down-drop complements this process and favours voluminous magma concentration. During the late evolutionary stages of pluton construction, the magma chamber was compartmentalized into NE-trending sectors affected by block rotation in an anticlockwise manner. Understanding the role of faults in the emplacement of the Naxos pluton is important for understanding emplacement of other plutons in the Aegean Sea region, since most of them are controlled by N–S- (Ikaria pluton) or NE- (Tinos, Serifos and Delos plutons) trending faults.

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Normal faulting on Sifnos and the South Cycladic Detachment System, Aegean Sea, Greece

Journal of the Geological Society ◽

10.1144/0016-76492010-064 ◽

2011 ◽

Vol 168 (3) ◽

pp. 751-768 ◽

Cited By ~ 38

Author(s):

Uwe Ring ◽

Johannes Glodny ◽

Thomas M. Will ◽

Stuart Thomson

Keyword(s):

Aegean Sea ◽

Normal Faulting ◽

The South

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Structure, tectonic processes and deformation of the South Aegean Sea

10.12681/eadd/50584 ◽

2021 ◽

Author(s):

Κωνσταντίνα Τσαμπουράκη-Κραουνάκη

Keyword(s):

Aegean Sea ◽

The South ◽

Tectonic Processes ◽

Back Arc

Η παρούσα διατριβή διερευνά τη μακροχρόνια παραμόρφωση και τους ενεργούς τεκτονικούς μηχανισμούς που συνέβαλαν στην εξέλιξη και στο σχηματισμό του πολύπλοκου ανάγλυφου του Νοτίου Αιγαίου. Παρά τις γεωλογικές έρευνες που έχουν διεξαχθεί στο Αιγαίο, μέχρι και σήμερα γνωρίζουμε πολύ λίγα για τη γεωδυναμική εξέλιξη του. Αν και είναι ευρέως αποδεκτό ότι στη γεωτεκτονική εξέλιξη της μικρο-πλάκας του Αιγαίου κυριαρχούν κυρίως οι εφελκυστικές διεργασίες παραμόρφωσης που συναντώνται σε ένα back-arc περιβάλλον (οπισθοτόξο), πρόσφατες γεωλογικές, σεισμολογικές και γεωδαιτικές μελέτες έχουν δείξει ότι η συνολικός εφελκυσμός δύναται να περιλαμβάνει και πλαγιό-συμπιεστικές και πλαγιό- εφελκυστικές διεργασίες. Η παρούσα διπλωματική εργασία συνοψίζει την προϋπάρχουσα βιβλιογραφία και τα κύρια μοντέλα παραμόρφωσης που έχουν προταθεί για το Αιγαίο και μέσω της παρουσίασης νέων βαθυμετρικών και σεισμικών δεδομένων στοχεύει στη βελτίωση της κατανόησης των τεκτονικών διεργασιών και των παραμορφώσεων που επικρατούν στο Νότιο Αιγαίο. Προκειμένου να αναπτυχθεί ένα γεωδυναμικό μοντέλο που θα εξηγεί τις κινηματικές διεργασίες και τους μηχανισμούς παραμόρφωσης που έλαβαν χώρα στην περιοχή, ο κύριος άξονας της διατριβής δομείται από τρεις κύριες ερευνητικές εργασίες, τα αποτελέσματα των οποίων παρέχουν νεότερες πληροφορίες για τη γεωδυναμική εξέλιξη του Νοτίου Αιγαίου.

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1881 and 1949 earthquakes at the Chios-Cesme Strait (Aegean Sea) and their relation to tsunamis

Natural Hazards and Earth System Science ◽

10.5194/nhess-5-717-2005 ◽

2005 ◽

Vol 5 (5) ◽

pp. 717-725 ◽

Cited By ~ 14

Author(s):

Y. Altinok ◽

B. Alpar ◽

N. Özer ◽

C. Gazioglu

Keyword(s):

Seismic Activity ◽

Aegean Sea ◽

Normal Faults ◽

Natural Phenomena ◽

Sea Waves ◽

The South ◽

Izmir Bay ◽

Moderate Size ◽

The North ◽

Narrow Bays

Abstract. The most earthquake-prone areas in the eastern central Aegean Sea are the Izmir Bay, the Karaburun peninsula and the island of Chios. The level of seismic activity and tsunami potential are influenced by the presence of normal faults around the region. There have been about 20 moderate-size earthquakes from 496 BC to 1949 AD. Among these earthquakes, the ones on the dates 20 March 1389, 13 November 1856, 19/22 January 1866, 3 April 1881 and 23 July 1949 produced tsunamis. The Chios-Cesme earthquake (1881, Mw 6.5) took place in the South of the Cesme strait while the Chios-Karaburun earthquake (1949, Mw 6.7) occurred in the North. The tsunamis caused by the earthquakes affected the coasts of Chios Island and Cesme. These waves are thought to be associated with the earthquakes and co-seismic underwater failures possibly occurred along the coasts of the Chios Island and Karaburun Peninsula or on the complex subaqueous morphology between these lands. Some sea waves or oscillations observed following the aftershocks are believed to be related to other natural phenomena; e.g. the seiches occurred mainly in open-narrow bays as triggered by the earthquakes.

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Morphotectonic analysis along the northern margin of Samos Island, related to the seismic activity of October 2020, Aegean Sea, Greece

10.5194/egusphere-egu21-3849 ◽

2021 ◽

Author(s):

Paraskevi Nomikou ◽

Dimitris Evangelidis ◽

Dimitris Papanikolaou ◽

Danai Lampridou ◽

Dimitris Litsas ◽

...

Keyword(s):

Seismic Activity ◽

Normal Fault ◽

Aegean Sea ◽

The South ◽

The West ◽

Northern Margin ◽

Hydrographic Survey ◽

Southern Margin ◽

Eastern Aegean ◽

Division Line

On October 30th 2020 a strong earthquake of magnitude 7.0 occurred north of Samos Island at the Eastern Aegean Sea. This seismic event was another destructive active deformation in the long seismic history of Samos since the ancient times. Preliminary reports focused the seismic epicenter at about 10 km north of Karlovassi, situated at the western part of the Samos E-W trending coastline. The earthquake mechanism corresponds to an E-W normal fault dipping to the north. The activated fault was assumed to be running along the northern margin of Samos Island, which bounds from the south the Samos basin.Immediately after the seismic activity and during the aftershock period in December 2020 an hydrographic survey off the northern coastal margin of Samos Island was conducted with R/V NAUTILOS of the Hellenic Navy Hydrographic Service, using the multibeam SeaBat 7160 RESON. The result of the hydrographic survey was a detailed bathymetric map with 15m grid interval and 50m isobaths.&#160; The main morphological aspects of Samos Basin are a 14 km long, 6 km wide and 690 m deep elongated E-W basin developed north of Samos Island.The southern margin of the basin is abrupt with morphological slopes of more than 10o, following the major E-W normal fault surface, running along the coastal zone, with an overall throw of more than 500m. In contrast, the northern margin of the basin shows a gradual slope increase towards the south from 1o to 5o. Numerous small canyons trending N-S transversal to the main direction of the Samos coastline are observed along the southern margin, between 600 and 100 m water depth. &#160;These canyons have a length around 2,7 km and width between 100-300 m. Two large submarine landslides with a canyon width of 1,3 km and 0,8 Km, are located north of Karlovasi. The creation of the canyons is probably due to the uplift of Northern Samos Island and their 500 m vertical height difference corresponds to the average fault throw that has controlled the steep slopes of the margin. The orientation of the fault scarp changes at the western Samos coastline from E-W to ENE-WSW facing the neighboring Ikaria Basin, which is developed to the west of Samos Basin. The division line between the Ikaria and Samos basins runs N-S from the northern slopes and coast of the Kerketeas mountain (1443m). The aftershocks of the 30th October main shock are limited east of the N-S division line with only a minor activity 15 km to the west within the eastern margin of the Ikaria Basin.

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Early Cultures of the South Anatolian Plateau

Anatolian Studies ◽

10.2307/3642460 ◽

1961 ◽

Vol 11 ◽

pp. 159-184 ◽

Cited By ~ 12

Author(s):

James Mellaart

Keyword(s):

Bronze Age ◽

Iron Age ◽

Alluvial Soil ◽

Aegean Sea ◽

List Type ◽

Neolithic Period ◽

The South ◽

Anatolian Plateau ◽

Distinct Unit ◽

Neolithic Cultures

The purpose of this article is to describe here some of the material found during our survey of the Konya Plain in 1958. In two previous articles pottery of the 2nd millennium and the Iron Age found here have already been published. That of the Early Bronze Age, the most prosperous period in this area, will be described at a later date, and the present article will only describe the pottery of the Neolithic and Chalcolithic periods, under the following headings:I.Neolithic cultures of the South Anatolian Plateau.II.The Early Chalcolithic in the Konya Plain.III.The Late Chalcolithic in the Konya Plain.The importance of the Konya Plain in Anatolian prehistory is obvious. It is the largest single plain on the whole of the Anatolian Plateau with alluvial soil, and as such it is the granary of Turkey. No other region on the plateau shows such numbers of ancient mounds, or so many mounds of great size. The survey of this region, geographically as well as archaeologically a distinct unit, has at last linked the western plateau with Cilicia, and the results have shown that there is now a cultural continuum from the borders of Syria to the Aegean Sea since the Neolithic period.

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Temperature and Conductivity as Indicators of the Morphology and Activity of a Submarine Volcano: Avyssos (Nisyros) in the South Aegean Sea, Greece

Geosciences ◽

10.3390/geosciences8060193 ◽

2018 ◽

Vol 8 (6) ◽

pp. 193 ◽

Cited By ~ 3

Author(s):

Evangelos Bakalis ◽

Theo Mertzimekis ◽

Paraskevi Nomikou ◽

Francesco Zerbetto

Keyword(s):

Aegean Sea ◽

Submarine Volcano ◽

The South

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40Ar/39Ar thermochronology in the Ios basement terrane resolves the tectonic significance of the South Cyclades Shear Zone

Geological Society London Special Publications ◽

10.1144/sp487-2018-169 ◽

2019 ◽

Vol 487 (1) ◽

pp. 291-313 ◽

Cited By ~ 1

Author(s):

Marnie Forster ◽

Oleg Koudashev ◽

Ruoran Nie ◽

Sonia Yeung ◽

Gordon Lister

Keyword(s):

Shear Zone ◽

High Vacuum ◽

Aegean Sea ◽

Potassium Feldspar ◽

Ultra High Vacuum ◽

The South ◽

Directed Movement ◽

Mineral Growth ◽

Diffusion Parameters ◽

Time Histories

AbstractWe conducted 39Ar diffusion experiments using potassium feldspar from the South Cyclades Shear Zone on Ios, in the Cyclades, Aegean Sea, Greece. Irradiated samples were step-heated in an ultra-high-vacuum resistance furnace attached to a mass spectrometer, thus also allowing 40Ar/39Ar geochronology. Conjoint inversion of these datasets allowed estimation of the relevant diffusion parameters, which were then used to forward model the effect of arbitrary temperature–time histories. Simulations used Monte Carlo methods to improve approximations to the observed age spectra. Two periods of rapid cooling could be inferred. The South Cyclades Shear Zone commenced operation during or shortly after the Eocene–Oligocene transition. Episodes of south-directed movement continued into Early Miocene time, however, with the footwall still hot enough to cause biotite ± garnet metamorphic mineral growth at the base of the overlying, already substantially exhumed, eclogite–blueschist unit. Since its footwall continued to cool, the South Cyclades Shear Zone was an extensional shear zone during both episodes of its operation.

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