Methana Research Articles

Geochemistry of hydrothermally influenced sediments off Methana (western Hellenic volcanic arc)

Surface sediment samples from near-shore shallow water as well as deeper water locations N and NE of the island of Methana were investigated geochemically. Shallow water samples from Thiafi Bay reveal up to 38-fold enrichment of As, associated with elevated contents of Sb, Fe and Zn. Deeper water samples NE of Methana show moderate Mn enrichment accompanied with elevated trace metal concentrations of As and, in some samples, Cd and Cu. In an area, where small mounds of possible hydrothermal origin were observed on the sea floor, fine-grained Fe-rich sediment was sampled with enrichment of typical hydrothermal trace elements As, P and Sb. Element enrichment in the investigated areas off Methana corresponds in terms of absolute concentrations and element suite to comparable hydrothermally influenced sediments from other locations of the Hellenic volcanic arc. The region between Methana peninsula and Aegina Island is not marked by vigorous hydrothermal activity, but localised enrichments of Fe and/or Mn, As, Sb as well as associated trace elements typically found in hydrothermally influenced sediments were identified.

Security and Settlement in the Mediaeval and Post-Mediaeval Peloponnese, Greece

Two recent publications have questioned the hypothesis that insecurity explains the later Ottoman period settlement pattern in the Greek Peloponnese. The present article re-examines the arguments against the demographic retreat hypothesis, focusing particularly on the evidence from a small case-study area, the peninsula of Methana. While previous discussion depended on historical documents, the present study incorporates material cultural and ethnographic evidence. It is argued that simple altitude zonation of settlements is an inadequate indicator of insecurity: the relationship of settlement to geomorphology, and non-settlement elements, such as hidden storage structures and details of house construction, contribute important evidence. However, the understanding of the meanings of all these elements is dependent on local ethnographic sources, especially oral histories. The article concludes that a genuine fear of attack explains the Methana settlement pattern, despite a lack of evidence that the fear was justified.

Magnetotelluric measurements on the Methana Peninsula (Greece): modelling and interpretation

As a first deep geophysical survey, thirteen magnetotelluric and magnetovariation soundings in the period range of 0.0085–6000 s have been carried out in the Methana Peninsula and Trizina area (Greece), which form the western part of the active Hellenic Volcanic Arc. Data have been processed using robust techniques and further analysed using decomposition methods in order to find the regional azimuth. By using the smooth inverse of Smith and Booker (J. Geophys. Res. 96, 3905–3922, 1991), the 2-D modelling has resolved a low-resistivity area (<30 Ω m) at depths of 2–3 km beneath the volcanics, whereas elsewhere the resistivity is much higher (>100 Ω m). Parkinson induction arrows also at the range 0.01–0.1 s point towards the centre of the peninsula. The conductivity anomaly is interpreted as being connected with the volcanic history of Methana, as a cooler remnant of former magmatic activity. The contrast with the much higher resistivities suggested at depths >5 km, is discussed in terms of fluid mobility, limitation of the MT method and extensional processes in the southern Aegean.

A Rough and Rocky Place: The Landscape and Settlement History of the Methana Peninsula, Greece. By Christopher Mee and Hamish Forbes.

The uncompromising nature of the landscape of the Methana Peninsula in Greece, and its overall isolation, have been dominating factors in the peninsula's history. This is a report of major fieldwork undertaken following a brief reconnaissance in the summer of 1981. A more detailed exploratory study was made a year later, and it soon became obvious that the settlement history of the peninsula was more complex than it had been thought to be, when a number of unrecorded sites were discovered. It also became clear that most previous reports had discussed known sites solely or primarily in terms of their architectural remains, and that the peninsula's settlement history would not be comprehensible without systematic study. A survey strategy was developed and a full field-survey season on Methana was undertaken with two teams in 1984, followed by further seasons in each of the next three years.

The Geochemistry of Hydrothermal Vent Waters from Milos Island, Hellenic Volcanic Arc

The Hellenic Volcanic Arc is a tectonically and volcanically active part of the earth's crust, situated above the subduction zone of the African plate under the Aegean. The arc extends from the Methana peninsula (NE Peloponese) through the greek islands Milos, Santorini, Kos, Nisiros and Yali to the Bodrum peninsula, Turkey (e.g. Fytikas et at., 1986). Hydrothermal venting has been reported from Nisiros, Yali (Varnavas and Cronan, 1991), Santorini (Varnavas and Cronan, 1988) and Milos (Fytikas, 1989). The island of Milos, at the central west part of the volcanic arc, is dominated by volcanic and voIcaniclastic rocks, with the exception of minor occurrences of metamorphic basement rocks and Neogene sediments outcropping at the south part of the island, underneath the volcanics (Fytikas et al., 1986). Submarine and, later, sub-aerial extrusive sequences formed during a prolonged period of volcanic activity (3.5 to 0.1 Ma, Fytikas, 1989). Geochemically, the Milos volcanics show a calcalkaline character and comprise andesites, dacites and ryolites (Fytikas et al., 1986). Hot water springs and fumaroles occur at several localities around the island. In submarine settings, hot fluids exit through the sandy seafloor, often in the form of a mixed liquid/ gas phase; as a result, venting can be located due to the visually impressive presence of streams of gas bubbles. In the most hydrothermally active south-east part of the island (Palaeohori bay), extensive areas of bacteria mats are associated with submarine hydrothermal brine seeps (Fitzsimons et al., 1997). Field observations and sampling

96/01727 Utilisation of straw and similar agricultural residues

Along the SAAVA, two subaereal volcanic fields host known historically active volcanic centers: 1. Methana, with an historic eruption registered in ∼230 BC, and 2. Santorini, with 10 registered historic eruptions, the last one in 1950. Two other volcanic fields are considered as potentially active volcanoes: 1. Nisyros, with historic hydrothermal explosions, the last one in 1887, and 2. Milos, with probable historic hydrothermal explosions during the 1–2nd century AD.In Methana peninsula, volcanic activity was mainly extrusive and effusive. Dangerous pyroclastic products (block and ash flows and related surges) are restricted nearby to the extrusive volcanic edifices. Volcanic hazard and risk in the area is low.Santorini is the most active volcanic field of the South Aegean volcanic arc, one of the world's most violent caldera volcanoes. It comprises two of the three active volcanic Aegean centres, these of Kameni and Kolumbo.The maximum expected event on Santorini is a catastrophic paroxysmal eruption like the Minoan event. The probability of occurrence of such an event in the near future is very low. The most probable event to occur on Santorini is one of post-Minoan type, like those that built up Nea Kameni and Kolumbo.The data available on the post-Minoan activity do not permit an accurate long-term forecasting of the next volcanic unrest. A short-term forecasting for the onset of such a type of activity is considered possible with an integral and efficiently operating monitoring network.In Milos volcanic field, the reactivating of the volcano with hazardous explosive hydrovolcanic eruptions (the maximum expected event) cannot be excluded. The most probable to occur event at Milos is that of a hydrothermal explosion, thus consisting a considerable natural hazard for the area. Volcanic risk in Milos island is relatively very low.On Nisyros, a very young stratovolcano (subaerial cone <160 ka), the hazard and risk evaluation on the maximum expected event, a phreatomagmatic eruption, cannot be estimated accurately. Such an event pose in grave danger not only Nisyros inhabitants but even the nearby area of Kos and the neighbouring coasts of Turkey. The hazard and risk of a hydrothermal explosion is relatively high, as numerous recent hydrothermal craters are present in the Nisyros caldera floor, area that is being visited by thousands of tourists during the summer time.Yali islet is an Upper Quaternary rhyolitic volcanic edifice. The very young age (probably Neolithic) of the last explosive eruption of Yali, lead us to consider even this centre as a potentially active volcano.Regarding the monitoring state of the active and potentially active volcanic centers, Santorini is the only area in which has been set up an integral monitoring system and a Volcano Observatory. Nisyros volcano is not efficiently monitored up to now. The same is valid for Milos and Methana volcanic fields

Volcanic rocks of methana, South Aegean arc, Greece

Cale-alkalic lavas and associated intrusives and cognate xenoliths, from the peninsula of Methana, are comparable geochemically with similar lavas from elsewhere in the South Aegean arc. At least four differentiation series have been recognized, largely of basaltic andesite to rhyodacite type, in which hydrous and dry conditions alternated.

Australian Blattidae (Blattodea) IX. Revision of the Polyzosteriinae tribe Methanini, Tryonicinae, and Blattinae

Keys are given to the subfamilies of Blattidae in Australia and to the tribes and genera of Polyzosteriinae. In Polyzosteriinae-Methanini, nine species of Methana Stal are redescribed, and M. athertonensis, sp. nov., is described; three species of Temnelytra Tepper are redescribed, and one new one, marksae, sp. nov., is named; one species of Scabina Shelford is redescribed; six species of Drymaplaneta Tepper are redescribed. In Tryonicinae, one species of Tryonicus Shaw is redescribed. In Blattinae, Austrostylopyga, gen. nov., is proposed for four species originally placed in Stylopyga or Neostylopyga, and A. quadriloba, sp. nov., is described. Notes are given on unnamed species of Methana, Tryonicus, and Austrostylopyga, and on the genus Dorylaea Stal which may occur in Australia.

A Petrographical Sketch of Ægina and Methana

Previous articleNext article FreeA Petrographical Sketch of Ægina and MethanaHenry S. WashingtonHenry S. Washington Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Journal of Geology Volume 2, Number 8Nov. - Dec., 1894 Article DOIhttps://doi.org/10.1086/607075 Views: 38 Citations: 6Citations are reported from Crossref PDF download Crossref reports the following articles citing this article:Davis Young Origin of the American Qantitative Igneous Rock Classification: Part 2, Earth Sciences History 28, no.22 (Nov 2009): 175–203.https://doi.org/10.17704/eshi.28.2.334n7uk31v1060g7Irene Polinskaya Fifth-Century Horoi on Aigina: A Reevaluation, Hesperia 78, no.22 (Jun 2009): 231–267.https://doi.org/10.2972/hesp.78.2.231G. G. Pe Volcanic rocks of methana, South Aegean arc, Greece, Bulletin Volcanologique 38, no.11 (Mar 1974): 270–290.https://doi.org/10.1007/BF02599408G. G. Pe Petrology and geochemistry of volcanic rocks of Aegina, Greece, Bulletin Volcanologique 37, no.44 (Dec 1973): 491–514.https://doi.org/10.1007/BF02596888Hans Pichler, Rudolf Stengelin Petrochemische und nomenklatorische Revision der Vulkanite des süd-ägäischen Raumes (Griechenland), Geologische Rundschau 57, no.33 (Oct 1968): 795–810.https://doi.org/10.1007/BF01845365Georg M. Paraskevopoulos �ber den Chemismus und die provinzialen Verh�ltnisse der terti�ren und quart�ren Ergu�gesteine des �g�ischen Raumes und der benachbarten Gebiete, Tschermaks Mineralogische und Petrographische Mitteilungen 6, no.1-21-2 (Jan 1956): 13–72.https://doi.org/10.1007/BF01128030