Geology

The Geological Evolution of the Aegean Region

Based on a synopsis of available observations the Aegean region is characterized as a young, small, inactive marginal basin with high heat flow in a somewhat hampered stage of development.

The Alpine Orogeny

Geological evolution: The origins of the Alpine orogeny

Petrology and Geochemistry of the Metamorphic System of Santorini

In this paper an older undersea volcanism (stratified volcanic rocks) of Athenios and Thermia is described. It is concluded from the mineralogical composition and the chemism that the initial material was andesitic to basic andesitic.

Thera as the Tectonic Focus of the South Aegean: Archaeological Evidence from the Aegean Margin

The author outlines the eustatic and tectonic changes around the Aegean margin over the last few thousand years, and puts forward the hypothesis that the margin of the south Aegean is broken into different separated fingers.

Geothermal Research on Santorini

Geochemical, geophysical, geological and thermometric research on Thera identified a region of high geothermal interest in the south part of the island (Akrotiri-Megalochori area).

Some Aspects of Lead and Silver Mining in the Aegean

The sources of lead and silver for Bronze Age artifacts, archaic coins etc. in the Greek world are not known with any certainty except in the case of Laurion, Attica. This article discusses briefly the nature and sources of our knowledge, the occurrence of silver and lead in nature, the lead isotope method and its application to tracing ancient mines, the date of first working of the Laurion mines, and new information about the ancient mines of Siphnos.

Marine Geological Research on Santorini: Preliminary Results

The islands of the Santorini complex (Thera, Therasia and others; Fig. 1) have been the site of extensive examination by geologists, because they comprise one of the most impressive geological sites in the world.

Climatic Change in the Eastern Mediterranean Area During The Past 240,000 Years

Climatic variability in the eastern Mediterranean area during the past 240,000 years has been determined from two sources: deep-sea sediment data from cores, providing information over longer periods of time, and terrestrial data utilizing non-marine sediments, for interpreting shorter period fluctuations.

Thermal Regime of the Aegean Area

By considering published heat-flow data of the Aegean area and the surrounding seas (Jongsma 1974; Erickson 1970) and a crustal model deduced from seismic and gravity data, Fig. 1 (Makris 1977), the temperature distribution of the Aegean Sea was computed.

Geological and Geochemical Evolution of the Santorini Volcano: a Review

A review of the existing information on the tectonic and magmatic evolution of Santorini indicates that the lavas so far erupted are cogenetic, have derived from a composite, probably two-component source, and exhibit typical intra-oceanic arc characteristics despite the intra-continental setting of the Aegean arc.

The Prevolcanic Basement of Thera at Athinios: Metamorphism, Plutonism and Mineralization

The prevolcanic basement of Thera at Athinios consists of metamorphosed pelites, sandstones, carbonates, conglomerates, cherts and volcanic rocks.

The Geochemistry of the Radial Dykes of the Santorini Caldera and its Implications

In the north-east wall of the modern Santorini caldera several radial dykes are exposed. Their major element chemistry changes from high-aluminum basalt to dacite in a calc-alkaline sequence.

Drilling of an Ore-Forming Shallow Hydrothermal System, Santorini Volcano, Greece

Low-cost drilling of the ore-forming shallow submarine hydrothermal system of Santorini volcano, under a joint project between the Institute of Geology and Mineral Exploration and the University of Stockholm, has placed important constraints on the modelling of hydrothermal processes in such tectonic settings, and established firm guidelines for related future research.

Chemistry of Hydrothermal Solutions in Drill Hole GPK-1, Palaea Kameni, Santorini, Greece

Drilling in a metalliferous hydrothermal system has been carried out at Pa1aea Kameni. The drill hole was set some 40 m north-north-east of the most intense hot springs on Pa1aea Kameni and stopped at a depth of 201.5 metres.

Petrology of the GPK-1 Drill-hole Lavas, Palaea kameni Hot Springs, Santorini Volcano, Greece: Constraints on the Low-T Lava Fluid Interaction

The lavas recovered in the GPK-1 bore hole, drilled under ajoint Institute of Geology and Mineral Exploration - University of Stockholm project in the close proximity of the Palaea Kameni hot springs are plagioclase + clinopyroxene + orthopyroxene + magnetite hyalopilitic dacites.

The Consequences of Volcanic Activity of the Minoan Period on the Hydrogeological Conditions of the Island of Thera

Long before the beginning of the paroxysmal volcanic activity during the Minoan period, due to weathering of the upper surface pyroclastic beds of the island of Thera, a palaeoedaphic formation was formed ranging in thickness from a few centimetres up to 8 metres.

Metallogenesis at Santorini a Subduction-zone Related Process. I: Deposition of Hydrothermal Sediments

Submarine hydrothermal springs deposit large amounts of Fe and Si and some trace constituents in a few protected bays on the Kameni islands, Santorini.

Metallogenesis at Santorini - a Subduction-zone Related Process. II: Geochemistry and Origin of Hydrothermal Solutions on Nea Kameni, Santorini, Greece

Several hot springs debouch on Nea Kameni, Santorini, particularily in a bay in the south-west of the island, where major deposition of iron - and silica-rich sediments takes place.

Geochemistry of Lavas, Pumice and Veins in Drill Core GPK-1, Palaea Kameni, Santorini

A petrogeochemical study has been made of a drill core from Palaea Kameni (GPK-1, length 201.5 metres) in order to understand the petrogenesis and the alteration of the rocks.

Petrographic Description of Marine Sediments from Santorini: Evidence for a New Submarine Hot-Spring Field in the Bottom of the Caldera

The sediments of the Santorini caldera and its surroundings have been examined by several scientists, to a large extent from a geochemical point of view(Butuzova 1969, 1978; Petersen and Müller 1974, 1976; Smith and Cronan 1978, 1983).

Spatial and Time Series Analysis of Santorini Hydrothermal Waters

Hydrothermal waters from six vents in the Palaea Kameni hydrothermally active embayment on Santorini have been analysed for Mn, Fe, Zn and Cd. In addition, time series analysis of chemical variations at one vent was carried out over a period of one year.

Geochemistry and Structural Control of Hydrothermal Sediments and New Hot Springs in the Caldera of Santorini, Greece

Sediments in the caldera of Santorini contain much detrital volcanics (pumice), but leaching experiments show that the removed fraction resembles hydrothermal matter from Nea and Palaea Kameni.

Provenance Studies of Theran Lead

The provenance of lead used for artefacts found at the Late Bronze Age settlement of Akrotiri is discussed.

The Geotectonic State of the Greek Area: Vulcanism, Intermediate Earthquakes and Plate Tectonics

Geological and geophysical data led us to suppose that the African plate in the Mediterranean area passes gradually from the cratonic to the geosynclinal state because of the action of convection currents, moving from NE to SW in the Aegean Sea, and from NW to SE in the Tyrrhenian Sea, towards the deep Ionian Sea (Kiskyras 1960).

Stone Materials in Ancient Akrotiri - A Short Compilation

During a visit in summer 1976 to the excavation site near Akrotiri/Santorini the materials used for buildings and requisites were examined. The materials were grouped on the basis of rock types. A short description of the materials and their use is given.

Geotectonic Significance of the Deep Seismic Zones in the Aegean Area

Several large and complete samples of data, concerning the distribution of earthquake foci, show that there are two distinct deep seismic zones in the Aegean area.

Evolution of the Volcanic Rocks of Santorini

From major and trace element determinations of Santorini rocks the consistency of differentiation history in all previous cycles, origin of magmas and mode of differentiation (crystallizing of ol, opx, cpx, mt, plg) was deduced, using the distribution coefficients of Puchelt & Kramar (1978).

Gravity Anomalies on the Thera Islands

Thera Islands form a caldera embracing Post-caldera domes at its centre. To discuss the mechanisms of caldera formations, one should know the present subsurface structure of the calderas.

Aegean Soils During the Second Millennium B.C. with Reference to Thera

The fact of extensive soil and landscape changes in the Aegean over the last few thousand years is widely accepted. The author presents and discusses evidence for such changes with reference to Melos and Thera.

Postvolcanic Activity of the Santorini Volcano and its influence on Sediment and Ore Formation

The Santorini volcano is at present at the postvolcanic stage of its development. In the volcanic caldera around the Neo Kameni island are localized numerous volcanic gas exhalations, hydrothermal springs attributed to the low-temperature type of mofettes with hydrogen sulphide manifestations varying in time and space.

The Ground Water Potential of Santorini Island

After a brief general review of the evolution and constitution of the islands of Santorini, the climatic environment is described, with special reference to the hydrometeorological regime.

Recent Tuffitic Sediments Around Santorini, Greece

Part IV : Geochemistry of the Iron-rich Sediments from the Santorini Caldera

Contribution to the Mineralogy of the Iron-Rich Mud Sediments of Santorini, Greece

The occurrences of iron-rich mud sediments in the caldera of Santorini around the volcanic islands of Nea Kameni and of Palea Kameni have been investigated with the aid of electron microscopic methods.

Geochemical Dispersion of Metals in and around the Caldera of Thera

The geochemical characteristics of sediments from the shelf and caldera of Santorini are described. Shelf sediments consist of two major facies. Uppermost are "normal" sediments with calcium carbonate, silt sized pumice fragments and a minor clay component.

Magnetic Studies of the Santorini Tephra Deposits

The Santorini tephra exposed just south of Phira and at the archaeological excavations at Akrotiri were sampled (Figure 1) in 1973 in order to investigate the possibility of detecting the presence, or absence, of a significant (20 - 30 years) interval between successive ash falls.

Petrochemical Study of the Tephra Sequence Exposed in the Phira Quarry, Thera

The mineralogy and petrochemistry of the Bronze Age tephra of the volcano Thera (Santorini) support the concept of magma chamber inversion during a single uninterrupted eruption.

Tephrochronological Evidence for the Time of the Bronze Age Eruption of Thera

Soil samples collected from archeologically dated levels at Kato Zakro on Crete and from Phylakopi on Melos contain microscopic particles of the Bronze Age Thera tephra, in contexts which are entirely consistent with an LM IA date for the eruption.