Émilie Écochard - Academia.edu (original) (raw)

Papers by Émilie Écochard

Research paper thumbnail of Approche géoarchéologique et valorisation du patrimoine géomorphologique autour du Létôon (plaine de Xanthos, Turquie)

Ce travail propose une reconstitution de l'evolution de l'environnement de la plaine term... more Ce travail propose une reconstitution de l'evolution de l'environnement de la plaine terminale de l'Esen Cayi depuis le milieu de l'Holocene, avec une attention particuliere pour l'environnement proche du sanctuaire du Letoon et de la cite de Xanthos, durant leur periode d'occupation (du viie siecle av. J.-C. jusqu'a la periode byzantine). La demarche retenue deploie trois approches. L'approche historique, d'abord, confronte les sources archeologiques, historiques, litteraires et geomorphologiques pour definir les enjeux de cette recherche et cerner les questions auxquelles elle doit repondre : l'objectif est de mieux comprendre les societes qui ont occupe cet espace et leur relation avec leur environnement. L'approche geo archeologique, ensuite, y repond en s'appuyant sur les donnees geophysiques (resistivite electrique) et l'analyse des sequences carottees (etude des sediments, datations). Il apparait qu'a l'epoque de l'occupation des sites, les lagunes qui occupaient auparavant cet espace avaient laisse place a des marais. Un changement dans le trace de l'Esen Cayi (un bras du fleuve s'installe temporairement devant le Letoon) facilite l'accessibilite du site depuis la mer, mais l'alluvionnement et la mobilite fluviale qui en resultent mettent aussi en danger les edifices, des le iiie siecle ap. J.-C. C'est seulement avec la mise en culture systematique de la plaine, durant la deuxieme moitie du xxe siecle, que les marais disparaissent et que la plaine est assainie et drainee. L'approche patrimoniale, enfin, permet une reflexion epistemologique et empirique sur la communication des resultats en direction des archeologues commanditaires, du public de visiteurs des sites et des habitants de la plaine. Le concept de geomorphosite, qui fournit une profondeur temporelle a un site aux caracteres geomorphologiques remarquables est sollicite pour definir la plaine de Xanthos comme un archeo-geomorphosite

Research paper thumbnail of Jouer en classe pour reconstituer un débat de société

Karthala eBooks, Jan 21, 2021

Research paper thumbnail of Dry? or Wet? Magma-Water Interaction during Minoan-Thera Eruption of Santorini depicted from 3D morphological analysis of Ashes

EGU General Assembly Conference Abstracts, Apr 1, 2012

ABSTRACT Powerful and, catastrophic Minoan-Thera eruption of Santorini occurred at mid-second mil... more ABSTRACT Powerful and, catastrophic Minoan-Thera eruption of Santorini occurred at mid-second millennium BC (~3300 BP) produced totally 30 km3 DRE of tephras (Sigurdsson et al., 1990; Pyle, 1990). Magnitude of Minoan-Thera of Santorini Late Bronze Age eruption was estimated as 6 (Colossal) to 7(super colossal) corresponding to Plinian/Ultraplinian style activity according to Volcanic Explosivity Index (McCoy&Heiken,2000). During this one of the largest eruptions in the human history, vent properties and eruption dynamics have changed from dry plinian phase (first phase) to wet phreatomagmatic surges and to pyroclastic flows, comprising of four distinct phases. Convective eruption cloud formed in the first phase was under influence of westerly winds, according to numerous published papers, extending toward east-northeast-southeast, toward Black Sea, Turkey, Mediterannean Sea. We drilled Letoon Plain, southwestern coast of Turkey and cut 3 cm thick tephra deposit overlying an organic material-rich layer dated as 1612 BC (C14, AMS method), corresponding well to the age of Minoan-Thera eruption. The iron content of Minoan-Thera tephras (≥ 2%) is higher than Turkish tephras (in general <2%). Grain size distribution of our Minoan-Thera tephra measured by Laser Sizer exhibits that drilled tephra is mostly fine-grained and 93 % of tephra is below 100 microns, meeting distal tephra characteristics. We examined the surficial morphological features of distal, fine grained tephra and applied some quantitative statistical parameters for surface descriptors of volcanic ashes such as "Average roughness of profile (Ra), Surface Area (SA), Volume (V), Fractal Dimension of Roughness (DAS), Projected Area (PA)". We compared quantitative morphological data acquired from Minoan-Thera eruption with that of well-known plinian style and phreatomagmatic eruptions derived from Central Turkey. Fragments of Minoan-Thera tephras either have tubular, spherical vesicles indicating magmatic fragmentation, or are sometimes blocky-equant, mosslike grains and curviplanar cut and shallow vesicles depicting typical phreatomagmatic fragmentation. We calculated True Surface Area (SA) and Plotted Area (PA) of ashes. SA/PA values of Santorini 63 µ deposits vary from 1.35 to 3.96, besides those of 125 µ range between 1.32-2.18. Comparing all SA/PA values, we can conclude that vesiculated ashes have SA/PA around 1.8 and over. Some are > 2 as polyhedron - multifractal unvesiculated glassy ashes. Meanwhile, blocky-equant ashes have SA/PA <1.6. On the correlative diagrams of surface descriptors, the intermediate character of Santorini tephras between Plinian deposits and Phreatomagmatic deposits is obvious. Ash surface morphology, surface descriptors, and the correlation with the known eruptions of distal tephras of Minoan-Thera indicate that the nature of the first phase of Minoan-Thera is not purely magmatic as it was classically claimed in most of the previous works.

Research paper thumbnail of Volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption (Santorini) in a distal setting, southwestern Turkey

Journal of Quaternary Science, Apr 26, 2021

ABSTRACTWe present the volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption of ... more ABSTRACTWe present the volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption of Santorini (LBAES) in a distal setting in southwestern Turkey. In one of the drilled cores at the Letoon Hellenic antique site on Eşençay Delta, we encountered a 4 cm thick tephra deposit underlain by 46 cm thick tsunami‐deposited sand (tsunamite), and an organic‐rich layer that we 14C dated to 3295 ± 30 bp or 1633 bc. The relationship between Santorini distal volcanic ash and underlying tsunamite is described and interpreted. LBAES occurred in four main phases: (1) plinian; (2) phreatomagmatic; (3) phreatomagmatic with mudflows; and (4) ignimbritic flows and co‐ignimbrite tephra falls. In this study, we aim to understand which eruptive phases generate distal ash during the Minoan eruptive sequence by examining the 3D surface morphology of ash formed by different fragmentation processes. To that end, we used numerous statistical multivariates, 3D fractal dimension of roughness, and a new textural parameter of surface area‐3D/plotted area‐2D to characterise the eruption dynamics. Based on ash surface morphologies and the calculated statistical parameters, we propose that that distal ash is represented by a single layer composed of well‐mixed (coarse to fine) magmatic and phreatomagmatic ash.

Research paper thumbnail of Dynamiques géomorphologiques et occupation du sanctuaire de Létôon (Plaine de Xanthos, Turquie) au cours des cinq milles dernières années. In Nathalie Carcaud et Gille Arnaud Fassetta (Edts.)

HAL (Le Centre pour la Communication Scientifique Directe), 2015

Research paper thumbnail of Paysage : approches qualitatives et quantitatives

Research paper thumbnail of Chapitre IV. Dynamiques géomorphologiques et occupation du sanctuaire de Létôon (Plaine de Xanthos, Turquie) au cours des cinq mille dernières années

CNRS Éditions eBooks, 2015

Research paper thumbnail of Geoarchaeological approach and geomorphological heritage management around the Letoon (plain of Xanthos, Turkey)

Ce travail propose une reconstitution de l'évolution de l'environnement de la plaine term... more Ce travail propose une reconstitution de l'évolution de l'environnement de la plaine terminale de l'Eşen Çayı depuis le milieu de l'Holocène, avec une attention particulière pour l'environnement proche du sanctuaire du Létôon et de la cité de Xanthos, durant leur période d'occupation (du viie siècle av. J.-C. jusqu'à la période byzantine). La démarche retenue déploie trois approches. L'approche historique, d'abord, confronte les sources archéologiques, historiques, littéraires et géomorphologiques pour définir les enjeux de cette recherche et cerner les questions auxquelles elle doit répondre : l'objectif est de mieux comprendre les sociétés qui ont occupé cet espace et leur relation avec leur environnement. L'approche géo archéologique, ensuite, y répond en s'appuyant sur les données géophysiques (résistivité électrique) et l'analyse des séquences carottées (étude des sédiments, datations). Il apparaît qu'à l'époque de l&#...

Research paper thumbnail of Dynamiques géomorphologiques et occupation du sanctuaire de Létôon (Plaine de Xanthos, Turquie) au cours des cinq milles dernières années. In Nathalie Carcaud et Gille Arnaud Fassetta (Edts.)

Research paper thumbnail of Volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption (Santorini) in a distal setting, southwestern Turkey

Journal of Quaternary Science, 2021

We present the volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption of Santorin... more We present the volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption of Santorini (LBAES) in a distal setting in southwestern Turkey. In one of the drilled cores at the Letoon Hellenic antique site on Eşençay Delta, we encountered a 4 cm thick tephra deposit underlain by 46 cm thick tsunami‐deposited sand (tsunamite), and an organic‐rich layer that we 14C dated to 3295 ± 30 bp or 1633 bc. The relationship between Santorini distal volcanic ash and underlying tsunamite is described and interpreted. LBAES occurred in four main phases: (1) plinian; (2) phreatomagmatic; (3) phreatomagmatic with mudflows; and (4) ignimbritic flows and co‐ignimbrite tephra falls. In this study, we aim to understand which eruptive phases generate distal ash during the Minoan eruptive sequence by examining the 3D surface morphology of ash formed by different fragmentation processes. To that end, we used numerous statistical multivariates, 3D fractal dimension of roughness, and a new textural parameter of surface area‐3D/plotted area‐2D to characterise the eruption dynamics. Based on ash surface morphologies and the calculated statistical parameters, we propose that that distal ash is represented by a single layer composed of well‐mixed (coarse to fine) magmatic and phreatomagmatic ash.

Research paper thumbnail of Dry? or Wet? Magma-Water Interaction during Minoan-Thera Eruption of Santorini depicted from 3D morphological analysis of Ashes

ABSTRACT Powerful and, catastrophic Minoan-Thera eruption of Santorini occurred at mid-second mil... more ABSTRACT Powerful and, catastrophic Minoan-Thera eruption of Santorini occurred at mid-second millennium BC (~3300 BP) produced totally 30 km3 DRE of tephras (Sigurdsson et al., 1990; Pyle, 1990). Magnitude of Minoan-Thera of Santorini Late Bronze Age eruption was estimated as 6 (Colossal) to 7(super colossal) corresponding to Plinian/Ultraplinian style activity according to Volcanic Explosivity Index (McCoy&Heiken,2000). During this one of the largest eruptions in the human history, vent properties and eruption dynamics have changed from dry plinian phase (first phase) to wet phreatomagmatic surges and to pyroclastic flows, comprising of four distinct phases. Convective eruption cloud formed in the first phase was under influence of westerly winds, according to numerous published papers, extending toward east-northeast-southeast, toward Black Sea, Turkey, Mediterannean Sea. We drilled Letoon Plain, southwestern coast of Turkey and cut 3 cm thick tephra deposit overlying an organic material-rich layer dated as 1612 BC (C14, AMS method), corresponding well to the age of Minoan-Thera eruption. The iron content of Minoan-Thera tephras (≥ 2%) is higher than Turkish tephras (in general <2%). Grain size distribution of our Minoan-Thera tephra measured by Laser Sizer exhibits that drilled tephra is mostly fine-grained and 93 % of tephra is below 100 microns, meeting distal tephra characteristics. We examined the surficial morphological features of distal, fine grained tephra and applied some quantitative statistical parameters for surface descriptors of volcanic ashes such as "Average roughness of profile (Ra), Surface Area (SA), Volume (V), Fractal Dimension of Roughness (DAS), Projected Area (PA)". We compared quantitative morphological data acquired from Minoan-Thera eruption with that of well-known plinian style and phreatomagmatic eruptions derived from Central Turkey. Fragments of Minoan-Thera tephras either have tubular, spherical vesicles indicating magmatic fragmentation, or are sometimes blocky-equant, mosslike grains and curviplanar cut and shallow vesicles depicting typical phreatomagmatic fragmentation. We calculated True Surface Area (SA) and Plotted Area (PA) of ashes. SA/PA values of Santorini 63 µ deposits vary from 1.35 to 3.96, besides those of 125 µ range between 1.32-2.18. Comparing all SA/PA values, we can conclude that vesiculated ashes have SA/PA around 1.8 and over. Some are > 2 as polyhedron - multifractal unvesiculated glassy ashes. Meanwhile, blocky-equant ashes have SA/PA <1.6. On the correlative diagrams of surface descriptors, the intermediate character of Santorini tephras between Plinian deposits and Phreatomagmatic deposits is obvious. Ash surface morphology, surface descriptors, and the correlation with the known eruptions of distal tephras of Minoan-Thera indicate that the nature of the first phase of Minoan-Thera is not purely magmatic as it was classically claimed in most of the previous works.

Research paper thumbnail of Palaeogeographical reconstruction and management challenges of an archaeological site listed by UNESCO: the case of the Letoon shrine in the Xanthos Plain (Turkey)

QUAGEO, 2012

Palaeogeographical reconstruction and management challenges of an archaeological site listed by U... more Palaeogeographical reconstruction and management challenges of an archaeological site listed by UNESCO: the case of the Letoon shrine in the Xanthos Plain (Turkey) During the Hellenistic period, Xanthos and Letoon were respectively a large city and an important shrine in Lycia. Questions still remain about the geography of the Eşen Çayı delta during the first millennium BC: what were the features of the landscape surrounding the Letoon shrine? Where did the riverbed lie? Our analysis is based on a reconstruction of the geomorphological dynamics at work during the Holocene. These are then compared with historical, archaeological and literary sources. Sedimentary sampling shows that a marine bay was gradually closed during the formation of a coastline spit, which led to the development of a lagoon system. Lagoons and marshes remained predominant characteristics of the plain over a long period. A branch or a former channel of the Eşen Çayı was discovered close to the Letoon shrine. In ...

Research paper thumbnail of Reconstructing the Geomorphological Evolution of the Plain of Xanthos (SW Turkey) during the Holocene: a Geoarchaeological Approach

Research paper thumbnail of Reconstitution paléogéographique des dynamiques paysagères durant l’Holocène autour de Xanthos et Létôon dans l’ancienne Lycie (Turquie) : premiers résultats

Norois, 2009

Reconstitution paléogéographique des dynamiques paysagères durant l'Holocène autour de Xanthos et... more Reconstitution paléogéographique des dynamiques paysagères durant l'Holocène autour de Xanthos et Létôon dans l'ancienne Lycie (Turquie) : premiers résultats

Research paper thumbnail of Paleogeographical reconstruction and management challenges of an archaeological site listed by UNESCO: Case of the plain of Xanthos and Letoon (Turkey)

Journal of Earth Science, 2010

Research paper thumbnail of Paléogéographie et reconstitution des dynamiques géomorphologiques à l’Holocène autour des sites archéologiques de Xanthos et Létôon (Turquie)

Research paper thumbnail of Jouer en classe pour reconstituer un débat de société

Enseigner les traites, les esclavages, les abolitions et leurs héritages

Research paper thumbnail of Approche géoarchéologique et valorisation du patrimoine géomorphologique autour du Létôon (plaine de Xanthos, Turquie)

Ce travail propose une reconstitution de l'evolution de l'environnement de la plaine term... more Ce travail propose une reconstitution de l'evolution de l'environnement de la plaine terminale de l'Esen Cayi depuis le milieu de l'Holocene, avec une attention particuliere pour l'environnement proche du sanctuaire du Letoon et de la cite de Xanthos, durant leur periode d'occupation (du viie siecle av. J.-C. jusqu'a la periode byzantine). La demarche retenue deploie trois approches. L'approche historique, d'abord, confronte les sources archeologiques, historiques, litteraires et geomorphologiques pour definir les enjeux de cette recherche et cerner les questions auxquelles elle doit repondre : l'objectif est de mieux comprendre les societes qui ont occupe cet espace et leur relation avec leur environnement. L'approche geo archeologique, ensuite, y repond en s'appuyant sur les donnees geophysiques (resistivite electrique) et l'analyse des sequences carottees (etude des sediments, datations). Il apparait qu'a l'epoque de l&#...

Research paper thumbnail of Chapitre IV. Dynamiques géomorphologiques et occupation du sanctuaire de Létôon (Plaine de Xanthos, Turquie) au cours des cinq mille dernières années

Research paper thumbnail of Chapter 1. Geoarchaeology during Late Glacial in northern France

La géoarchéologie française au xxie siècle, 2015

Research paper thumbnail of Approche géoarchéologique et valorisation du patrimoine géomorphologique autour du Létôon (plaine de Xanthos, Turquie)

Ce travail propose une reconstitution de l'evolution de l'environnement de la plaine term... more Ce travail propose une reconstitution de l'evolution de l'environnement de la plaine terminale de l'Esen Cayi depuis le milieu de l'Holocene, avec une attention particuliere pour l'environnement proche du sanctuaire du Letoon et de la cite de Xanthos, durant leur periode d'occupation (du viie siecle av. J.-C. jusqu'a la periode byzantine). La demarche retenue deploie trois approches. L'approche historique, d'abord, confronte les sources archeologiques, historiques, litteraires et geomorphologiques pour definir les enjeux de cette recherche et cerner les questions auxquelles elle doit repondre : l'objectif est de mieux comprendre les societes qui ont occupe cet espace et leur relation avec leur environnement. L'approche geo archeologique, ensuite, y repond en s'appuyant sur les donnees geophysiques (resistivite electrique) et l'analyse des sequences carottees (etude des sediments, datations). Il apparait qu'a l'epoque de l'occupation des sites, les lagunes qui occupaient auparavant cet espace avaient laisse place a des marais. Un changement dans le trace de l'Esen Cayi (un bras du fleuve s'installe temporairement devant le Letoon) facilite l'accessibilite du site depuis la mer, mais l'alluvionnement et la mobilite fluviale qui en resultent mettent aussi en danger les edifices, des le iiie siecle ap. J.-C. C'est seulement avec la mise en culture systematique de la plaine, durant la deuxieme moitie du xxe siecle, que les marais disparaissent et que la plaine est assainie et drainee. L'approche patrimoniale, enfin, permet une reflexion epistemologique et empirique sur la communication des resultats en direction des archeologues commanditaires, du public de visiteurs des sites et des habitants de la plaine. Le concept de geomorphosite, qui fournit une profondeur temporelle a un site aux caracteres geomorphologiques remarquables est sollicite pour definir la plaine de Xanthos comme un archeo-geomorphosite

Research paper thumbnail of Jouer en classe pour reconstituer un débat de société

Karthala eBooks, Jan 21, 2021

Research paper thumbnail of Dry? or Wet? Magma-Water Interaction during Minoan-Thera Eruption of Santorini depicted from 3D morphological analysis of Ashes

EGU General Assembly Conference Abstracts, Apr 1, 2012

ABSTRACT Powerful and, catastrophic Minoan-Thera eruption of Santorini occurred at mid-second mil... more ABSTRACT Powerful and, catastrophic Minoan-Thera eruption of Santorini occurred at mid-second millennium BC (~3300 BP) produced totally 30 km3 DRE of tephras (Sigurdsson et al., 1990; Pyle, 1990). Magnitude of Minoan-Thera of Santorini Late Bronze Age eruption was estimated as 6 (Colossal) to 7(super colossal) corresponding to Plinian/Ultraplinian style activity according to Volcanic Explosivity Index (McCoy&Heiken,2000). During this one of the largest eruptions in the human history, vent properties and eruption dynamics have changed from dry plinian phase (first phase) to wet phreatomagmatic surges and to pyroclastic flows, comprising of four distinct phases. Convective eruption cloud formed in the first phase was under influence of westerly winds, according to numerous published papers, extending toward east-northeast-southeast, toward Black Sea, Turkey, Mediterannean Sea. We drilled Letoon Plain, southwestern coast of Turkey and cut 3 cm thick tephra deposit overlying an organic material-rich layer dated as 1612 BC (C14, AMS method), corresponding well to the age of Minoan-Thera eruption. The iron content of Minoan-Thera tephras (≥ 2%) is higher than Turkish tephras (in general <2%). Grain size distribution of our Minoan-Thera tephra measured by Laser Sizer exhibits that drilled tephra is mostly fine-grained and 93 % of tephra is below 100 microns, meeting distal tephra characteristics. We examined the surficial morphological features of distal, fine grained tephra and applied some quantitative statistical parameters for surface descriptors of volcanic ashes such as "Average roughness of profile (Ra), Surface Area (SA), Volume (V), Fractal Dimension of Roughness (DAS), Projected Area (PA)". We compared quantitative morphological data acquired from Minoan-Thera eruption with that of well-known plinian style and phreatomagmatic eruptions derived from Central Turkey. Fragments of Minoan-Thera tephras either have tubular, spherical vesicles indicating magmatic fragmentation, or are sometimes blocky-equant, mosslike grains and curviplanar cut and shallow vesicles depicting typical phreatomagmatic fragmentation. We calculated True Surface Area (SA) and Plotted Area (PA) of ashes. SA/PA values of Santorini 63 µ deposits vary from 1.35 to 3.96, besides those of 125 µ range between 1.32-2.18. Comparing all SA/PA values, we can conclude that vesiculated ashes have SA/PA around 1.8 and over. Some are > 2 as polyhedron - multifractal unvesiculated glassy ashes. Meanwhile, blocky-equant ashes have SA/PA <1.6. On the correlative diagrams of surface descriptors, the intermediate character of Santorini tephras between Plinian deposits and Phreatomagmatic deposits is obvious. Ash surface morphology, surface descriptors, and the correlation with the known eruptions of distal tephras of Minoan-Thera indicate that the nature of the first phase of Minoan-Thera is not purely magmatic as it was classically claimed in most of the previous works.

Research paper thumbnail of Volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption (Santorini) in a distal setting, southwestern Turkey

Journal of Quaternary Science, Apr 26, 2021

ABSTRACTWe present the volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption of ... more ABSTRACTWe present the volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption of Santorini (LBAES) in a distal setting in southwestern Turkey. In one of the drilled cores at the Letoon Hellenic antique site on Eşençay Delta, we encountered a 4 cm thick tephra deposit underlain by 46 cm thick tsunami‐deposited sand (tsunamite), and an organic‐rich layer that we 14C dated to 3295 ± 30 bp or 1633 bc. The relationship between Santorini distal volcanic ash and underlying tsunamite is described and interpreted. LBAES occurred in four main phases: (1) plinian; (2) phreatomagmatic; (3) phreatomagmatic with mudflows; and (4) ignimbritic flows and co‐ignimbrite tephra falls. In this study, we aim to understand which eruptive phases generate distal ash during the Minoan eruptive sequence by examining the 3D surface morphology of ash formed by different fragmentation processes. To that end, we used numerous statistical multivariates, 3D fractal dimension of roughness, and a new textural parameter of surface area‐3D/plotted area‐2D to characterise the eruption dynamics. Based on ash surface morphologies and the calculated statistical parameters, we propose that that distal ash is represented by a single layer composed of well‐mixed (coarse to fine) magmatic and phreatomagmatic ash.

Research paper thumbnail of Dynamiques géomorphologiques et occupation du sanctuaire de Létôon (Plaine de Xanthos, Turquie) au cours des cinq milles dernières années. In Nathalie Carcaud et Gille Arnaud Fassetta (Edts.)

HAL (Le Centre pour la Communication Scientifique Directe), 2015

Research paper thumbnail of Paysage : approches qualitatives et quantitatives

Research paper thumbnail of Chapitre IV. Dynamiques géomorphologiques et occupation du sanctuaire de Létôon (Plaine de Xanthos, Turquie) au cours des cinq mille dernières années

CNRS Éditions eBooks, 2015

Research paper thumbnail of Geoarchaeological approach and geomorphological heritage management around the Letoon (plain of Xanthos, Turkey)

Ce travail propose une reconstitution de l'évolution de l'environnement de la plaine term... more Ce travail propose une reconstitution de l'évolution de l'environnement de la plaine terminale de l'Eşen Çayı depuis le milieu de l'Holocène, avec une attention particulière pour l'environnement proche du sanctuaire du Létôon et de la cité de Xanthos, durant leur période d'occupation (du viie siècle av. J.-C. jusqu'à la période byzantine). La démarche retenue déploie trois approches. L'approche historique, d'abord, confronte les sources archéologiques, historiques, littéraires et géomorphologiques pour définir les enjeux de cette recherche et cerner les questions auxquelles elle doit répondre : l'objectif est de mieux comprendre les sociétés qui ont occupé cet espace et leur relation avec leur environnement. L'approche géo archéologique, ensuite, y répond en s'appuyant sur les données géophysiques (résistivité électrique) et l'analyse des séquences carottées (étude des sédiments, datations). Il apparaît qu'à l'époque de l&#...

Research paper thumbnail of Dynamiques géomorphologiques et occupation du sanctuaire de Létôon (Plaine de Xanthos, Turquie) au cours des cinq milles dernières années. In Nathalie Carcaud et Gille Arnaud Fassetta (Edts.)

Research paper thumbnail of Volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption (Santorini) in a distal setting, southwestern Turkey

Journal of Quaternary Science, 2021

We present the volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption of Santorin... more We present the volcanic ash and tsunami record of the Minoan Late Bronze Age Eruption of Santorini (LBAES) in a distal setting in southwestern Turkey. In one of the drilled cores at the Letoon Hellenic antique site on Eşençay Delta, we encountered a 4 cm thick tephra deposit underlain by 46 cm thick tsunami‐deposited sand (tsunamite), and an organic‐rich layer that we 14C dated to 3295 ± 30 bp or 1633 bc. The relationship between Santorini distal volcanic ash and underlying tsunamite is described and interpreted. LBAES occurred in four main phases: (1) plinian; (2) phreatomagmatic; (3) phreatomagmatic with mudflows; and (4) ignimbritic flows and co‐ignimbrite tephra falls. In this study, we aim to understand which eruptive phases generate distal ash during the Minoan eruptive sequence by examining the 3D surface morphology of ash formed by different fragmentation processes. To that end, we used numerous statistical multivariates, 3D fractal dimension of roughness, and a new textural parameter of surface area‐3D/plotted area‐2D to characterise the eruption dynamics. Based on ash surface morphologies and the calculated statistical parameters, we propose that that distal ash is represented by a single layer composed of well‐mixed (coarse to fine) magmatic and phreatomagmatic ash.

Research paper thumbnail of Dry? or Wet? Magma-Water Interaction during Minoan-Thera Eruption of Santorini depicted from 3D morphological analysis of Ashes

ABSTRACT Powerful and, catastrophic Minoan-Thera eruption of Santorini occurred at mid-second mil... more ABSTRACT Powerful and, catastrophic Minoan-Thera eruption of Santorini occurred at mid-second millennium BC (~3300 BP) produced totally 30 km3 DRE of tephras (Sigurdsson et al., 1990; Pyle, 1990). Magnitude of Minoan-Thera of Santorini Late Bronze Age eruption was estimated as 6 (Colossal) to 7(super colossal) corresponding to Plinian/Ultraplinian style activity according to Volcanic Explosivity Index (McCoy&Heiken,2000). During this one of the largest eruptions in the human history, vent properties and eruption dynamics have changed from dry plinian phase (first phase) to wet phreatomagmatic surges and to pyroclastic flows, comprising of four distinct phases. Convective eruption cloud formed in the first phase was under influence of westerly winds, according to numerous published papers, extending toward east-northeast-southeast, toward Black Sea, Turkey, Mediterannean Sea. We drilled Letoon Plain, southwestern coast of Turkey and cut 3 cm thick tephra deposit overlying an organic material-rich layer dated as 1612 BC (C14, AMS method), corresponding well to the age of Minoan-Thera eruption. The iron content of Minoan-Thera tephras (≥ 2%) is higher than Turkish tephras (in general <2%). Grain size distribution of our Minoan-Thera tephra measured by Laser Sizer exhibits that drilled tephra is mostly fine-grained and 93 % of tephra is below 100 microns, meeting distal tephra characteristics. We examined the surficial morphological features of distal, fine grained tephra and applied some quantitative statistical parameters for surface descriptors of volcanic ashes such as "Average roughness of profile (Ra), Surface Area (SA), Volume (V), Fractal Dimension of Roughness (DAS), Projected Area (PA)". We compared quantitative morphological data acquired from Minoan-Thera eruption with that of well-known plinian style and phreatomagmatic eruptions derived from Central Turkey. Fragments of Minoan-Thera tephras either have tubular, spherical vesicles indicating magmatic fragmentation, or are sometimes blocky-equant, mosslike grains and curviplanar cut and shallow vesicles depicting typical phreatomagmatic fragmentation. We calculated True Surface Area (SA) and Plotted Area (PA) of ashes. SA/PA values of Santorini 63 µ deposits vary from 1.35 to 3.96, besides those of 125 µ range between 1.32-2.18. Comparing all SA/PA values, we can conclude that vesiculated ashes have SA/PA around 1.8 and over. Some are > 2 as polyhedron - multifractal unvesiculated glassy ashes. Meanwhile, blocky-equant ashes have SA/PA <1.6. On the correlative diagrams of surface descriptors, the intermediate character of Santorini tephras between Plinian deposits and Phreatomagmatic deposits is obvious. Ash surface morphology, surface descriptors, and the correlation with the known eruptions of distal tephras of Minoan-Thera indicate that the nature of the first phase of Minoan-Thera is not purely magmatic as it was classically claimed in most of the previous works.

Research paper thumbnail of Palaeogeographical reconstruction and management challenges of an archaeological site listed by UNESCO: the case of the Letoon shrine in the Xanthos Plain (Turkey)

QUAGEO, 2012

Palaeogeographical reconstruction and management challenges of an archaeological site listed by U... more Palaeogeographical reconstruction and management challenges of an archaeological site listed by UNESCO: the case of the Letoon shrine in the Xanthos Plain (Turkey) During the Hellenistic period, Xanthos and Letoon were respectively a large city and an important shrine in Lycia. Questions still remain about the geography of the Eşen Çayı delta during the first millennium BC: what were the features of the landscape surrounding the Letoon shrine? Where did the riverbed lie? Our analysis is based on a reconstruction of the geomorphological dynamics at work during the Holocene. These are then compared with historical, archaeological and literary sources. Sedimentary sampling shows that a marine bay was gradually closed during the formation of a coastline spit, which led to the development of a lagoon system. Lagoons and marshes remained predominant characteristics of the plain over a long period. A branch or a former channel of the Eşen Çayı was discovered close to the Letoon shrine. In ...

Research paper thumbnail of Reconstructing the Geomorphological Evolution of the Plain of Xanthos (SW Turkey) during the Holocene: a Geoarchaeological Approach

Research paper thumbnail of Reconstitution paléogéographique des dynamiques paysagères durant l’Holocène autour de Xanthos et Létôon dans l’ancienne Lycie (Turquie) : premiers résultats

Norois, 2009

Reconstitution paléogéographique des dynamiques paysagères durant l'Holocène autour de Xanthos et... more Reconstitution paléogéographique des dynamiques paysagères durant l'Holocène autour de Xanthos et Létôon dans l'ancienne Lycie (Turquie) : premiers résultats

Research paper thumbnail of Paleogeographical reconstruction and management challenges of an archaeological site listed by UNESCO: Case of the plain of Xanthos and Letoon (Turkey)

Journal of Earth Science, 2010

Research paper thumbnail of Paléogéographie et reconstitution des dynamiques géomorphologiques à l’Holocène autour des sites archéologiques de Xanthos et Létôon (Turquie)

Research paper thumbnail of Jouer en classe pour reconstituer un débat de société

Enseigner les traites, les esclavages, les abolitions et leurs héritages

Research paper thumbnail of Approche géoarchéologique et valorisation du patrimoine géomorphologique autour du Létôon (plaine de Xanthos, Turquie)

Ce travail propose une reconstitution de l'evolution de l'environnement de la plaine term... more Ce travail propose une reconstitution de l'evolution de l'environnement de la plaine terminale de l'Esen Cayi depuis le milieu de l'Holocene, avec une attention particuliere pour l'environnement proche du sanctuaire du Letoon et de la cite de Xanthos, durant leur periode d'occupation (du viie siecle av. J.-C. jusqu'a la periode byzantine). La demarche retenue deploie trois approches. L'approche historique, d'abord, confronte les sources archeologiques, historiques, litteraires et geomorphologiques pour definir les enjeux de cette recherche et cerner les questions auxquelles elle doit repondre : l'objectif est de mieux comprendre les societes qui ont occupe cet espace et leur relation avec leur environnement. L'approche geo archeologique, ensuite, y repond en s'appuyant sur les donnees geophysiques (resistivite electrique) et l'analyse des sequences carottees (etude des sediments, datations). Il apparait qu'a l'epoque de l&#...

Research paper thumbnail of Chapitre IV. Dynamiques géomorphologiques et occupation du sanctuaire de Létôon (Plaine de Xanthos, Turquie) au cours des cinq mille dernières années

Research paper thumbnail of Chapter 1. Geoarchaeology during Late Glacial in northern France

La géoarchéologie française au xxie siècle, 2015