{"title":"New data on the Dogger - Cenomanian stratigraphy of Tripolitza series in Central Crete","authors":"Α. Ζαμπετακη Λεκκα, Α. Αλεξοπουλοσ","doi":"10.12681/BGSG.17096","DOIUrl":"https://doi.org/10.12681/BGSG.17096","url":null,"abstract":"","PeriodicalId":9519,"journal":{"name":"Bulletin of the Geological Society of Greece","volume":"6 1","pages":"565"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81351610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This contribution refers to the history of the International Union of Geological Sciences (IUGS) initiative for the inventory and compilation of the global geosites list, "The geosite project". This project that started in1996 came as a consequence of the recent years discussion in international level, geological sites to be included in global site-based conservation and protection projects and in the world heritage list of UNESCO.The Global Geosites Working Group set up by International Union of Geological Sciences (IUGS) with the support of UNESCO in 1995, undertook the initiative for the systematic inventory of the most important sites, above all for the needs of the geological sciences research and education. The project aims also, to involve the whole geological community in geoconservation, as well as to support any national or international initiative to protect geodiversity, a recourse completely unrenewable. In Europe the whole pilot work for the geosites project is carried out by ProGEO, the European Association for the geological-geomorphological heritage conservation. ProGEO to which most of Europe's nations are represented by members, through regular international congresses, meetings, workshops, has led the way for the project, supported by its regional working groups and its national representatives (Greece belongs to the ProGEO WG1 of south-eastern Europe).
{"title":"Γεωλογικό πλαίσιο για την επιλογή γεώτοπων σύμφωνα με τις προδιαγραφές της Διεθνούς Ένωσης Γεωεπιστημών (IUGS) και της Ευρωπαϊκής Εταιρείας για τη Διατήρηση της Γεωλογικής - Γεωμορφολογικής Κληρονομιάς (ProGEO). Πρώτη Φάση: Ετοιμασία ενός πρώτου πλαισίου σε επίπεδο χώρας","authors":"Ε. ΘΕΟΔΟΣΙΟΥ - ΔΡΑΝΔΑΚΗ","doi":"10.12681/bgsg.17702","DOIUrl":"https://doi.org/10.12681/bgsg.17702","url":null,"abstract":"This contribution refers to the history of the International Union of Geological Sciences (IUGS) initiative for the inventory and compilation of the global geosites list, \"The geosite project\". This project that started in1996 came as a consequence of the recent years discussion in international level, geological sites to be included in global site-based conservation and protection projects and in the world heritage list of UNESCO.The Global Geosites Working Group set up by International Union of Geological Sciences (IUGS) with the support of UNESCO in 1995, undertook the initiative for the systematic inventory of the most important sites, above all for the needs of the geological sciences research and education. The project aims also, to involve the whole geological community in geoconservation, as well as to support any national or international initiative to protect geodiversity, a recourse completely unrenewable. In Europe the whole pilot work for the geosites project is carried out by ProGEO, the European Association for the geological-geomorphological heritage conservation. ProGEO to which most of Europe's nations are represented by members, through regular international congresses, meetings, workshops, has led the way for the project, supported by its regional working groups and its national representatives (Greece belongs to the ProGEO WG1 of south-eastern Europe).","PeriodicalId":9519,"journal":{"name":"Bulletin of the Geological Society of Greece","volume":"48 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83667343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The fossilized association as well as the pétrographie material coming from a sedimentary basin (ca. 30 km2) situated at the SE part of Crete, between the Provinces Viannos and Ierapetra are studied. The fossiliferous regions are in the area of the villages Myrtos, Mournies and Gdochia. Among an important number of fossils (154 taxons): 83 Foraminifers, 19 Bivalves, 24 Gastropods, Ostracods, 3 Echinoids, 13 Anthozoans, 1 Scaphopods, 6 Bryozoans, 2 Algues etc. there are some characteristic species of the Upper Tortonian age- especially Gl. obliquus extremus (zone of G. numerosa)- found in these sediments known up today generally as Miocene. The Tortonian age are based also on the occurrence of the species: Spondylus concentricus, Chlamys submalvinea, Chlamys solarium, Gryphaea gingensis, Gryphaea gryphoides crassissima, Turritella formata pseudoimbricata, Terebralia bidentata bidentata, Pontes collegniana, Palaeoplesiastraea desmoulinsi, Tarbellastraea carryensis, Thegioastraea rosacea etc. Based on the faunal and floral association and their morphofunctional analysis, their conditions of existence etc. the author attempts to interpret the paleoenvironmental conditions during the timespan of the Upper Tortonian, like as patch reefs or micro-atolls and lagoons.
{"title":"Paleoecological observations of the corals reefs of the upper Tortonian between Viannos - Ierapetra provinces (SE Crete)","authors":"A. MARCOPOULOU - DIACANTONI","doi":"10.12681/bgsg.16979","DOIUrl":"https://doi.org/10.12681/bgsg.16979","url":null,"abstract":"The fossilized association as well as the pétrographie material coming from a sedimentary basin (ca. 30 km2) situated at the SE part of Crete, between the Provinces Viannos and Ierapetra are studied. The fossiliferous regions are in the area of the villages Myrtos, Mournies and Gdochia. Among an important number of fossils (154 taxons): 83 Foraminifers, 19 Bivalves, 24 Gastropods, Ostracods, 3 Echinoids, 13 Anthozoans, 1 Scaphopods, 6 Bryozoans, 2 Algues etc. there are some characteristic species of the Upper Tortonian age- especially Gl. obliquus extremus (zone of G. numerosa)- found in these sediments known up today generally as Miocene. The Tortonian age are based also on the occurrence of the species: Spondylus concentricus, Chlamys submalvinea, Chlamys solarium, Gryphaea gingensis, Gryphaea gryphoides crassissima, Turritella formata pseudoimbricata, Terebralia bidentata bidentata, Pontes collegniana, Palaeoplesiastraea desmoulinsi, Tarbellastraea carryensis, Thegioastraea rosacea etc. Based on the faunal and floral association and their morphofunctional analysis, their conditions of existence etc. the author attempts to interpret the paleoenvironmental conditions during the timespan of the Upper Tortonian, like as patch reefs or micro-atolls and lagoons.","PeriodicalId":9519,"journal":{"name":"Bulletin of the Geological Society of Greece","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81146468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Danelian, M. Bonneau, J. Cadet, A. Poisson, Β. Vrielynck
Middle Oxfordian-early Kimmeridgian radiolaria, extracted from the top of radiolarites of Profitis Ilias unit (Rhodes island), suggest that the latter are essentially Middle Jurassic in age and the overlying siliceous shales Late Jurassic. The previously identified Calpionellid horizon at the top of Profitis Ilias siliceous marls is now regarded as early Valanginian in age. The above chronostratigraphic constraints allow tentative correlations to be made between Profitis Ilias and Pindos-Olonos sedimentary units. Finally, the palaeoceanographic significance of the studied series in Rhodes and potentially similar pelagic sequences in the Marmaris area of Turkey are discussed.
{"title":"Palaeoceanographic implications of new and revised bio-chronostratigraphic constraints from the Profitis Ilias Unit (Rhodes, Greece)","authors":"T. Danelian, M. Bonneau, J. Cadet, A. Poisson, Β. Vrielynck","doi":"10.12681/BGSG.17111","DOIUrl":"https://doi.org/10.12681/BGSG.17111","url":null,"abstract":"Middle Oxfordian-early Kimmeridgian radiolaria, extracted from the top of radiolarites of Profitis Ilias unit (Rhodes island), suggest that the latter are essentially Middle Jurassic in age and the overlying siliceous shales Late Jurassic. The previously identified Calpionellid horizon at the top of Profitis Ilias siliceous marls is now regarded as early Valanginian in age. The above chronostratigraphic constraints allow tentative correlations to be made between Profitis Ilias and Pindos-Olonos sedimentary units. Finally, the palaeoceanographic significance of the studied series in Rhodes and potentially similar pelagic sequences in the Marmaris area of Turkey are discussed.","PeriodicalId":9519,"journal":{"name":"Bulletin of the Geological Society of Greece","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78030413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Messinian biostratigraphy based on foraminifera and Ostracodes was studied in several surface sections within Peqin-Durres region. The sections are located in the eastern and northwestern part of the Peri-Adriatic Foredeep (PAF) of Albania (FigJ ). The Thartor section is located more or less in the center of the region studied. Its Messinian sediments in particular late Messinian one are well exposed and just in this place they represent the boundary of great differences between these sediments and those that could be occurred towards east or towards south. Firstly, here well distinguished the preevaporitic sequence which very rapidly wedge-out towards southeast. Secondly, here is the latest southeast boundary of gypsum blocks occurrence. Moreover in this section the lack of "lago-mare" biofacies is apparently owing to its erosion. Towards northern and western sections the lower boundary of "lago-mare" biofacies is well determined lithologically and faunistically. Towards southeast and eastern sections this boundary determined also by first occurrence of Cyprideis, Candona etc., as above but it seems to be not synchronous from section to section. In this aspect this "lago-mare" biofacies is more similar with a Paratethyan biofacies. Within the gypsum bearing region "lago-mare" biofacies is focused in the latest Messinian only, in this aspect it could be called "Tethyan lago-mare' biofacies.
{"title":"Messinian biostratigraphy based on foraminifera and ostracodes in Ionian zone of Albania","authors":"K. Buli, S. Prillo, Ν. BULl, L. Kumati, R. ROQl","doi":"10.12681/BGSG.17109","DOIUrl":"https://doi.org/10.12681/BGSG.17109","url":null,"abstract":"Messinian biostratigraphy based on foraminifera and Ostracodes was studied in several surface sections within Peqin-Durres region. The sections are located in the eastern and northwestern part of the Peri-Adriatic Foredeep (PAF) of Albania (FigJ ). The Thartor section is located more or less in the center of the region studied. Its Messinian sediments in particular late Messinian one are well exposed and just in this place they represent the boundary of great differences between these sediments and those that could be occurred towards east or towards south. Firstly, here well distinguished the preevaporitic sequence which very rapidly wedge-out towards southeast. Secondly, here is the latest southeast boundary of gypsum blocks occurrence. Moreover in this section the lack of \"lago-mare\" biofacies is apparently owing to its erosion. Towards northern and western sections the lower boundary of \"lago-mare\" biofacies is well determined lithologically and faunistically. Towards southeast and eastern sections this boundary determined also by first occurrence of Cyprideis, Candona etc., as above but it seems to be not synchronous from section to section. In this aspect this \"lago-mare\" biofacies is more similar with a Paratethyan biofacies. Within the gypsum bearing region \"lago-mare\" biofacies is focused in the latest Messinian only, in this aspect it could be called \"Tethyan lago-mare' biofacies.","PeriodicalId":9519,"journal":{"name":"Bulletin of the Geological Society of Greece","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91135723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Η γεωλογία στην Α'Βάθμια Εκπαίδευση. Δυνατότητες και προοπτικές","authors":"Α. X. Ροκκα","doi":"10.12681/bgsg.17705","DOIUrl":"https://doi.org/10.12681/bgsg.17705","url":null,"abstract":"","PeriodicalId":9519,"journal":{"name":"Bulletin of the Geological Society of Greece","volume":"14 1","pages":"819"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86088950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper concerns the study of a transgressive series, which overlies the upperjurassic oolitic limestones of subpelagonian zone, as well as the lateritic deposits, resulting from the alteration of the ophiolitic and fill the karstic cavities of the above mentioned limestones in NE Beotia (Fig.l). The purpose of this study is to• elucidate the age of the transgression, that occurred on the Jurassic limestones of the pelagonian platform at this region.• Discuss about the observed diachronism of the Late Cretaceous transgression on the Pelagonian platform.It is based on the study of micro- and macrofauna occurred in a section we describe in the "Marmeiko" area, on the Ptoon mountain. NOETH (1931) was the first who defined as Upper Turonian the age of the transgressive series, based on the study of Rudists. Later, BIGNOT & GUERNET (1968) studied the microfauna and attributed an age of lower Senonian. STEUBER (1993) based on the study of Hippuritidae, defined as Turonian and later (1995) as Turonian - Coniacian the age of the transgessive series. The basal part of the series consists of marls and marly limestones alternations. An abundant micro and macrofauna is found in this part of the section, as well as the first Rudist biostrome. In the middle part of the section 2 Rudist biostroms alternate with bioclastic limestones, containing abundant microfauna. In the upper part marls alternate with cherty limestones. The determinated micro- and macrofauna (Fig. 1), precises the age of the transgressive series as Santonian. This result confirms the diachronism of the transgressive phenomenon on the Pelagonian Upper- Jurassic limestones and the overthrusted ophiolites (AUBOUIN et al. 1960, BRUNN et al. 1972, KALLERGIS & ALBANTAKIS 1970, MAVRIDIS et al. 1979, NOETH 1931, BIGNOT & GUERNET 1968, CLEMENT & FERRIERE 1973, BIGNOT et al. 1973, STEUBER 1993, 1995, SKARPELIS & ZAMBETAKIS – LEKKAS 1998)
{"title":"New paleontological and stratigraphical data on the upper - cretaceous transgression of the Pelagonian zone s.l. (Marmeiko, Ptoon Mt. NE Beotia)","authors":"Α. Μερμιγκη, Α. Μαρκοπουλου Διακαντωνη, Α. Ζαμπετακη Λεκκα","doi":"10.12681/BGSG.17104","DOIUrl":"https://doi.org/10.12681/BGSG.17104","url":null,"abstract":"This paper concerns the study of a transgressive series, which overlies the upperjurassic oolitic limestones of subpelagonian zone, as well as the lateritic deposits, resulting from the alteration of the ophiolitic and fill the karstic cavities of the above mentioned limestones in NE Beotia (Fig.l). The purpose of this study is to• elucidate the age of the transgression, that occurred on the Jurassic limestones of the pelagonian platform at this region.• Discuss about the observed diachronism of the Late Cretaceous transgression on the Pelagonian platform.It is based on the study of micro- and macrofauna occurred in a section we describe in the \"Marmeiko\" area, on the Ptoon mountain. NOETH (1931) was the first who defined as Upper Turonian the age of the transgressive series, based on the study of Rudists. Later, BIGNOT & GUERNET (1968) studied the microfauna and attributed an age of lower Senonian. STEUBER (1993) based on the study of Hippuritidae, defined as Turonian and later (1995) as Turonian - Coniacian the age of the transgessive series. The basal part of the series consists of marls and marly limestones alternations. An abundant micro and macrofauna is found in this part of the section, as well as the first Rudist biostrome. In the middle part of the section 2 Rudist biostroms alternate with bioclastic limestones, containing abundant microfauna. In the upper part marls alternate with cherty limestones. The determinated micro- and macrofauna (Fig. 1), precises the age of the transgressive series as Santonian. This result confirms the diachronism of the transgressive phenomenon on the Pelagonian Upper- Jurassic limestones and the overthrusted ophiolites (AUBOUIN et al. 1960, BRUNN et al. 1972, KALLERGIS & ALBANTAKIS 1970, MAVRIDIS et al. 1979, NOETH 1931, BIGNOT & GUERNET 1968, CLEMENT & FERRIERE 1973, BIGNOT et al. 1973, STEUBER 1993, 1995, SKARPELIS & ZAMBETAKIS – LEKKAS 1998)","PeriodicalId":9519,"journal":{"name":"Bulletin of the Geological Society of Greece","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81919025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The reservoir of Platanovrysi in the Nestos valley has a long and narrow shape, limited in area and volume, deep close to the dam wall (90 m) and very shallow at its uphill end (5m). It receives considerable volume of water from the upper large reservoir of Thesaurus all through the year, as well as limited volumes of water in seasonal flows from its drainage basin. Platanovrysi reservoir has distinct morphological and operational characteristics that make it different from natural lakes regarding temperature and dissolved oxygen distribution in the water column. The epilimnion is limited at the area of the deeper part of the lake only. It forms an entrapped warm wedge, with the maximum depth close to the dam and a horizontal extension up to the beginning of the shallow part of the lake. This is due to both the inflows of large volumes of cold water from Thesaurus as well as the lack of a surface outflow from the dam of Platanovrysi. The water temperatures of the surface water of the upper part of the lake as well as the temperatures of the hypolimnion are similar. The temperature is very low during the spring and the summer (6-7°C), becomes higher during autumn (14-15°C) and drops again during winter (9-10°C). This shifting of seasonal temperatures is purely due to the inflows of cold water from the hypolimnion of the reservoir of Thesaurus in spring and summer periods and from the base of epilimnion during autumn. The water is rich in oxygen during the spring and the summer while it becomes poor in oxygen during the autumn and the beginning of winter. The operation of Platanovrysi Power Station allows the cold water from the hypolimnion of the lake to flow into the river Nestos channel and brings cold water during the warm period of the year downstream. This type of change of the water temperature may affect the natural processes of the river fauna and flora as well as the human processes in the plains of Nestos (irrigation). It is therefore necessary to construct and operate the last (lower) reservoir of Temenos in Nestos, to regulate the flow and warm the water of the river Nestos channel.
{"title":"Some characteristics of the new reservoir of Platanovrysi that affect the river Nestos system","authors":"Κωνσταντίνος Αλμπανάκης, Αντώνιος Ψιλοβίκος, Κ. Βουβαλίδης","doi":"10.12681/bgsg.17137","DOIUrl":"https://doi.org/10.12681/bgsg.17137","url":null,"abstract":"The reservoir of Platanovrysi in the Nestos valley has a long and narrow shape, limited in area and volume, deep close to the dam wall (90 m) and very shallow at its uphill end (5m). It receives considerable volume of water from the upper large reservoir of Thesaurus all through the year, as well as limited volumes of water in seasonal flows from its drainage basin. Platanovrysi reservoir has distinct morphological and operational characteristics that make it different from natural lakes regarding temperature and dissolved oxygen distribution in the water column. The epilimnion is limited at the area of the deeper part of the lake only. It forms an entrapped warm wedge, with the maximum depth close to the dam and a horizontal extension up to the beginning of the shallow part of the lake. This is due to both the inflows of large volumes of cold water from Thesaurus as well as the lack of a surface outflow from the dam of Platanovrysi. The water temperatures of the surface water of the upper part of the lake as well as the temperatures of the hypolimnion are similar. The temperature is very low during the spring and the summer (6-7°C), becomes higher during autumn (14-15°C) and drops again during winter (9-10°C). This shifting of seasonal temperatures is purely due to the inflows of cold water from the hypolimnion of the reservoir of Thesaurus in spring and summer periods and from the base of epilimnion during autumn. The water is rich in oxygen during the spring and the summer while it becomes poor in oxygen during the autumn and the beginning of winter. The operation of Platanovrysi Power Station allows the cold water from the hypolimnion of the lake to flow into the river Nestos channel and brings cold water during the warm period of the year downstream. This type of change of the water temperature may affect the natural processes of the river fauna and flora as well as the human processes in the plains of Nestos (irrigation). It is therefore necessary to construct and operate the last (lower) reservoir of Temenos in Nestos, to regulate the flow and warm the water of the river Nestos channel.","PeriodicalId":9519,"journal":{"name":"Bulletin of the Geological Society of Greece","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83086112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Factor analysis carried out in thirteen sediment cores, collected from an active pockmark field area in the eastern part of the Gulf of Patras, discriminated a domestic sewage pollution factor, the Mn/Fe oxides and the carbonate sedimentation. The increased content in sand, the low C content as well as the lack of C /heavy org org" J metals association follow a specific NW-SE transect in the centre of the surveyed pockmark field, suggesting pockmarks activity. This seems to control sedimentation and heavy metals distributions.
{"title":"Effects of an active pockmark field on the distribution of heavy metals of surficial sediments in the Gulf of Patras, Greece","authors":"J. Ravasopoulos, G. Papatheodorou, J. Kapolos","doi":"10.12681/BGSG.17133","DOIUrl":"https://doi.org/10.12681/BGSG.17133","url":null,"abstract":"Factor analysis carried out in thirteen sediment cores, collected from an active pockmark field area in the eastern part of the Gulf of Patras, discriminated a domestic sewage pollution factor, the Mn/Fe oxides and the carbonate sedimentation. The increased content in sand, the low C content as well as the lack of C /heavy org org\" J metals association follow a specific NW-SE transect in the centre of the surveyed pockmark field, suggesting pockmarks activity. This seems to control sedimentation and heavy metals distributions.","PeriodicalId":9519,"journal":{"name":"Bulletin of the Geological Society of Greece","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73089718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper examines the marine area of the Bay of Navarino and the Ionian sea sector to the west of the bay, based on a collection of shallow and intermediate penetration seismic profiles and on three gravity cores. The Bay has a smooth sea bottom morphology with maximum depth (75m) toward the south. Two minor reefs penetrate the sea bottom, one of them rising above the sea level forming a rocky island. In the open sea area the sea bottom is anomalous, especially after the shelf break, that is distinguished at a depth of approx. 160m. Beyond this depth deep valleys and ridges alternate and produce a rough morphology. The examination of the three gravity cores indicated that their sediment sand composition is mainly biogenic with minor amounts of terrigenous material. Increased shell fragments and terrigenous material was found at the bottom of one core taken at a depth of 116m, related probably to wave action at an earlier sea level position. The study of the seismic profiles collected within the bay and in the shelf area revealed,the presence of two distinct sedimentation units, un upper A filling with loose sediments the basins that are formed in the lower Y which is the basement. Within unit A two distinct subunits are recognized Al and A2, separated by an unconformity. In the sector to the west of the bay and beyond the shelf break, alternating opaque and transparent sediment packages are present, that are attributed to earlier sedimentation phases of low/high sea level stages. An older shelf break feature correlated with sea level stage 6 was distinguished at approx. 250m. sea depth. Thus subsidence rate in the area is estimated between 1 and 2 mm/year. The comparison of all data with the known sea level change curve indicated that unit AI was deposited during and after the latest transgression (stage 1) the unconformity between Al and A2 is related to the previous regression (stage 2), while the deposition of the unit A2 took place probably during stages 3 and/or 5. The morphology of the basement Y in the bay and the shelf area is thus attributed probably to stage 6 when the area was again subaerially exposed.
{"title":"Marine geological researches in the greater bay of Navarino area, Southern Ionian sea","authors":"Κ. Περισορατησ, Ν. Κονισπολιατησ, Ε. Ζημιανιτησ, Σταυρούλα Γαλανοπούλου, Πολυξένη Ζαχαράκη","doi":"10.12681/BGSG.17125","DOIUrl":"https://doi.org/10.12681/BGSG.17125","url":null,"abstract":"This paper examines the marine area of the Bay of Navarino and the Ionian sea sector to the west of the bay, based on a collection of shallow and intermediate penetration seismic profiles and on three gravity cores. The Bay has a smooth sea bottom morphology with maximum depth (75m) toward the south. Two minor reefs penetrate the sea bottom, one of them rising above the sea level forming a rocky island. In the open sea area the sea bottom is anomalous, especially after the shelf break, that is distinguished at a depth of approx. 160m. Beyond this depth deep valleys and ridges alternate and produce a rough morphology. The examination of the three gravity cores indicated that their sediment sand composition is mainly biogenic with minor amounts of terrigenous material. Increased shell fragments and terrigenous material was found at the bottom of one core taken at a depth of 116m, related probably to wave action at an earlier sea level position. The study of the seismic profiles collected within the bay and in the shelf area revealed,the presence of two distinct sedimentation units, un upper A filling with loose sediments the basins that are formed in the lower Y which is the basement. Within unit A two distinct subunits are recognized Al and A2, separated by an unconformity. In the sector to the west of the bay and beyond the shelf break, alternating opaque and transparent sediment packages are present, that are attributed to earlier sedimentation phases of low/high sea level stages. An older shelf break feature correlated with sea level stage 6 was distinguished at approx. 250m. sea depth. Thus subsidence rate in the area is estimated between 1 and 2 mm/year. The comparison of all data with the known sea level change curve indicated that unit AI was deposited during and after the latest transgression (stage 1) the unconformity between Al and A2 is related to the previous regression (stage 2), while the deposition of the unit A2 took place probably during stages 3 and/or 5. The morphology of the basement Y in the bay and the shelf area is thus attributed probably to stage 6 when the area was again subaerially exposed.","PeriodicalId":9519,"journal":{"name":"Bulletin of the Geological Society of Greece","volume":"28 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91544868","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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