- Email: [email protected]
Subglacial till behaviour derived from in situ wireless multi-sensor subglacial probes: Rheology, hydro-mechanical interactions and till formation
188
Abstracts / Quaternary International 279-280 (2012) 121–232
distribution. The progressive decline in the coercivity of the antiferromagnetic minerals in bulk samples throughout the whole period is mainly an expression of changes in the detrital fraction, reflecting changes in the source region, possibly involving increased aluminium substitution. The good correlation between DRS-defined hematite and frequency-dependent magnetic susceptibility in several chronologically defined subgroups of samples is consistent with the hypothesis that maghemite forms a transitional phase in a weathering sequence from ferrihydrite to hematite. The results shed new light on using HIRM to characterize hematite and goethite in sediments and on the history of weathering and climate change over the last 22 Ma in the dust source regions and on the Loess Plateau. THE DISTRIBUTION AND VULNERABILITIES OF CARBON IN PERMAFROST LANDSCAPES Jennifer Harden. U.S.Geological Survey, United States E-mail address: [email protected]
Carbon storage in northern landscapes reflects the climatic and environmental history under which C has accumulated. While the influence of temperature protects C from decomposition, water content and phase also regulate stabilization and destabilization of C on a variety of spatial scales: Topographic controls on solar insolation likely contribute to patterns of C storage with aspect and relief. Soil drainage affects moisture content and thermal properties, which interact to influence patterns of C storage with respect to combustion and vegetation. We have distinguished upland from lowland landscapes as separate pathways for regional warming to propagate through permafrost landscapes. In uplands, C becomes vulnerable mainly through top-down thaw and hillslope mobilization through surface and subsurface flow. In lowlands, permafrost C becomes vulnerable through thermokarst and lateral expansion of water bodies. Estimating C emissions from permafrost landscapes, however, requires both spatial and temporal components to account for different disturbance regimes, soil types, and permafrost characteristics. Here we explore key attributes of carbon, disturbance regime, landscape change, and feedbacks that must be quantified in order to estimate C emissions from degrading permafrost landscapes. SYNCHRONIZING HIGH-RESOLUTION POLLEN RECORDS FROM THE LAST GLACIAL (C.20-50 KA BP) USING TEPHROCHRONOLOGY: TESTING FOR ‘LEADS’ AND ‘LAGS’ DURING ENVIRONMENTAL TRANSITION Mark Hardiman. Centre for Quaternary Research, Department of Geog, United Kingdom E-mail address: [email protected]
Abrupt environmental transitions have been inferred from southern Europe based on multiple high resolution pollen records spanning the Last Glacial (c.20-50 Ka BP). These shifts have largely been related to Dansgaard-Oeschger cycles and Heinrich events. However, establishing the synchronicity, the ‘leads’ and ‘lags’, and regional variation of vegetation shifts is hampered by chronological uncertainties. Problems with the most commonly used technique, radiocarbon dating, include the old carbon effect in carbonate basins, lack of suitable sample material and calibration uncertainties, particularly for age estimates older than c.18 Ka BP. Due to these problems pollen stratigraphies are frequently aligned with other records. This procedure does not allow for the recognition of ‘leads’ and ‘lags’ in the environmental system and assumes that different proxies responded in a similar way to a common climatic forcing mechanism. Here we report on an approach that has the potential to overcome these difficulties. We present tephrochronological data from three sites in the eastern Mediterranean region– Kopais, Tenaghi Philippon and Lesvos. Some of the ash layers are non-visible ‘micro’ or ‘crypto’ tephras which have been assigned to volcanic source using both major, minor (EPMA) and trace element (LA-ICP-MS and SIMS) geochemical data from single shard analyses. Tephra layers correlated between sites can be used firstly to create a more precise ordering of palaeoenvironmental events and secondly to synchronise multiple records utilising Bayesian age-modelling techniques. The ability to use multiple tephra horizons to establish the relative phasing of vegetation changes across three terrestrial pollen sites
in the eastern Mediterranean region is fully explored; the chronological and palaeoenvironmental implications will be outlined. GEOCHRONOLOGICAL RECONSTRUCTION OF THE PLEISTOCENE FLUVIAL INCISION OF THE MOSELLE RIVER AND ITS MAIN TRIBUTARIES THE MEURTHE AND SARRE RIVERS (FRANCE, GERMANY) Dominique Harmand. Université Nancy 2, France E-mail address: [email protected]
The fluvial terrace sequence of the main rivers flowing through the Eastern Paris Basin and the western Rhenish Massif has been intensively studied during the last decade. The multi-proxy study included morphological, sedimentological and geochronological approaches. The latter was based both on ESR for the Marne and the Aisne catchments, and on OSL for the lower terraces of the Moselle River and its tributaries. This chronological framework has recently been complemented with the obtention of 15 ESR datings of fluvial sediments from the Upper and Lower Moselle, the Meurthe, and the Sarre rivers. These yielded ages ranging from 0.2 and 1.9 Ma. The age estimates make it possible to update the previous chronostratigraphical framework for the Moselle catchment and in particular to demonstrate that the so-called “main terrace complex” of the Mosel and Saar valleys corresponds with stepped terraces related to different aggradation periods during the Lower Pleistocene. The results also improve the knowledge of the fluvial response to glacial-interglacial cycles, and provide evidence for a more or less constant incision rate estimated at 10 cm.ka 1 both in the Eastern Paris Basin and the Rhenish Massif. QUATERNARY RECORDS OF THE CONTINENTAL SHELF AND LOWER COASTAL PLAIN, SOUTH CAROLINA (USA): EXAMPLES OF WELLPRESERVED STRATIGRAPHIC RECORD AND DISTINCT LANDSCAPES FROM MIS-5 TO THE PRESENT M. Scott Harris. College of Charleston, United States E-mail address: [email protected]
The Continental Shelf and Coastal Plain of the southeastern United States contain a superior record of emergent coastal barrier system strata and geomorphologies as well as a sparsely distributed, but well-preserved landscape on a sediment-starved shelf. This paper presents the current state of knowledge on the stratigraphic deposits and geomorphic landscape developed during the last interglacial (MIS-5), to the last glacial lowstand, to the current sea level and modern coastal barrier systems. A geological understanding of these Pleistocene and Holocene landscapes as related to coastal management, marine spatial planning, and essential fish habitats is the purpose of our studies in this region. Using multibeam bathymetry, sidescan sonar, high-resolution subbottom profiles, ground penetrating radar, and LiDAR surveys of the last glacial maximum (LGM) deposits on the edge of the continental shelf to the emerged MIS-5 coastal systems, we present high-resolution interpretations of a variety of coastal, marine, and terrestrial landscapes. MIS-5 deposits comprise wellpreserved transgressive and regressive coastal systems with abundant, weakly altered landforms. LGM deposits are represented by a definable set of near-surface reflectors at a consistent depth along the edge of the shelf below 120m. Younger-Dryas swamp deposits and tidal channels frequently cover the shelf between the 20m and 25m isobaths. Modern coastal systems range from short drumstick barriers with many inlets to headland-attached strand beaches. These extend seaward into a complex array of sand, shell, mud, and rocky deposits exposed and reworked on the active shoreface. Mapping and delineating this heterogeneous patchwork of unconsolidated sediment interspersed with rocky plains and ledges will continue to be a priority to coastal managers, fishery scientists, and marine spatial planners over the next two decades. SUBGLACIAL TILL BEHAVIOUR DERIVED FROM IN SITU WIRELESS MULTI-SENSOR SUBGLACIAL PROBES: RHEOLOGY, HYDROMECHANICAL INTERACTIONS AND TILL FORMATION Jane Hart. University of Southampton, United Kingdom E-mail address: [email protected]
Abstracts / Quaternary International 279-280 (2012) 121–232
189
The rheology and hydro-mechanical interactions at the ice-bed interface form an important component of the glacier system, influencing glacier dynamics and the formation of till. We demonstrate that the sand-rich tills at Briksdalsbreen in Norway and Skalafellsjökull, Iceland, undergo deformation throughout the year, but with different styles. On the bulk rheology scale, till deformation exhibits elastic behaviour during the winter, when water pressures are low; and linear viscous behaviour after a critical yield stress of 35 kPa, when water pressures are high during the spring and summer. On the clast and matrix scale, low water pressures, correspond with high case stress variability and till temperatures. Meltwater driven, stick-slip, glacier velocity increases were transmitted through a relatively strong till grain network, causing brittle deformation. Intermediate water pressures, during late summer were linked to intermediate case stress variability and high till temperatures associated with the heat generated from stick-slip motion. High water pressures in the till were associated with low case stress variability and low, meltwater controlled, till temperatures, and occurred in the spring and autumn. Once the till was saturated, the ductile till absorbed any stick-slip velocity increases. We discuss, with examples, the different till forming processes associated with these changing conditions, demonstrating that the resultant till will represent a complex amalgamation of all of these processes.
seawater. The model integrates hydrological, technological and economic considerations, and estimates the economic and environmental impacts of alternative water management policies; it was implemented in a case study in Israel. We constructed a unique hydrological database with data for each hydrological cell and applied a hydrological model for planning the allocation of the water resources and forecasting the concentration of chlorides in the aquifer under alternative scenarios. These scenarios included a variety of threshold policies for water supply. We developed an economic model that estimated the costs of various desalination processes, and calculated the costs of the water supply to the region under these scenarios. The hydrological model produces annual forecasts of chloride concentration in groundwater, while the economic model produces forecasts of the implementation costs. The conclusions from calculating the costs of improving the threshold chloride levels in the water supplies to city and/or agriculture or the steady-state levels in the aquifer are that desalination of brackish water involves the lowest costs, desalination of wastewater is significant for maintaining the chloride concentration threshold in water for agriculture, and desalination of seawater is recommended to maintain the national water balance. We conclude that the economic cost of improving the quality of the supplied water and of the aquifer water should be considered in decision making.
THE NEW LAKES – TERMINATION 1 COMPARED TO RECENT PROCESSES (IN SWISS ALPS AND A GLOBAL COMPARISON)
MAGNETIC FINGERPRINTING OF GREENLANDIC SEDIMENTS Robert Hatfield. Oregon State University, United States
Cédric Hartmann. University of Bern, Switzerland
E-mail address: rhatfi[email protected]
E-mail address: [email protected]
As is well-known from dating, fast deglaciation after the Last Glacial Maximum (LGM) caused glacial lakes as known as the Schweizer Alpenrandseen. By looking at these dates, recovered by 14C-Methode from unconsolidated sediment including organic matter deposited on top of till, it stands out that the ages of the dates from Swiss Foreland compared to the ones from the Alps are practical the same. This gives us the indication for an assumption that the enormous ice mass, which was distributed in most parts of Swiss Foreland, melted down and the glaciers retreated to the inneralpine passes in a very short time phase. In present days in alpine area deglaciation is proceeding fast again and is producing sub-, supra- or proglacial lakes. Not much is known about genesis of glacier lakes or better why the Swiss Lakes never have been filled up with sediments as in normal case while glacial retreat? And how it looks like globally? Do we have the same phenomena there? So we try to compare foreign literature with following analysis. We attempt to give an overview on the topic glacial lake and ask the question if there are parallels from the paleo- to the presentsituation? It is a challenge to display the comparison of these two time sequences and to reveal basic phenomena what these lakes are. For that we use features like different kind of maps, profiles and pictures from the last 10 to 20 years to get a better overview and then compare it to literature. But also mapping of the investigation areas, Trift-, Unteraar- and Rhône-Glacier should give us further information for the studies. The mentioned areas are chosen by following criteria: There is a significant retreat of the glacier in present time, they are all producing lake systems on or in front of the glacier in last decades and they bring different preconditions (steepness, underground, wide-ness of valley, etc.) with. Further investigations will be done till fall 2011 to clarify those problems and open questions. A MODEL FOR INTEGRATED WATER RESOURCES MANAGEMENT IN WATER-SCARCE REGIONS: MINIMIZATION OF THE IMPACTS OF GROUNDWATER EXPLOITATION ON SOCIETY AND THE ENVIRONMENT
In principle the geologic record of previous Greenland Ice Sheet (GIS) deglaciations can provide a context from which to assess present and future behaviors. The question is how to accurately trace ice sheet retreat for times when no terrestrial evidence remains. The marine record records these past variation, but deconvolving the integrated signal into ice sheet behavior is a non-trivial problem. By developing sediment fingerprints it may be possible to trace sediment export and determine when specific areas of Greenland became ice-free. A precursor to any such approach is the establishment of a comprehensive dataset that characterizes and discriminates between potential sources so that robust fingerprints can be constructed. Here we present particle-size magnetic data from sediments collected from the three main geological terranes of southern Greenland and basalts from Iceland. Samples were split into six particle size fractions with magnetic susceptibility showing the magnetic signal to be dominantly carried in the medium-fine silt fractions (45-10 mm) of the sediments. Significant intra-fraction variation within samples means that apparent discrimination based on measurement of bulk sediments could reflect grain-size variations rather than geological diversity; thus fingerprints should only be constructed on a particle size basis. Initial particlesize specific magnetic remanence results show magnetic similarities within terranes and variation between magnetic terranes, replicable over several particle size fractions. Comparison of these terrestrial fingerprints to oceanic cores through events when GIS mass wasting was highest (i.e. glacial terminations) should allow estimation of the relative amounts of sediment export from Greenland's three terranes; linked to the geographical extent of the GIS. These fingerprints can also aid understanding of other processes operating proximally to the GIS; e.g. the strength of the WBUC and/or understanding of IRD sources. COSMOGENIC 10BE EXPOSURE DATING OF ANCIENT QUARRIES IN WESTERN TURKEY Esther Haudenschild. Institut für Geologie, Switzerland E-mail address: [email protected]
Nava Haruvy. Netanya Academic College, Israel E-mail address: [email protected]
Israel as a water scarce country increased its exploitation of groundwater resources, which has caused problems of local aquifer contamination. Urban development and adoption of water desalination and irrigation with wastewater accelerate groundwater salinity and climatic change will further exacerbate these problems. We developed a model for planning water supply from diverse sources, including groundwater wastewater and
Kestanbol Granite, outcropping in the Ezine village of Çanakkale, was operated by the Romans for the production and export of building stones since ancient times. Today, remnant building stones can still be found in the ruins of these quarries, whose extent and operation periods are unknown, although archaeologists roughly estimate a Roman period from 500 BC to 500 AD. Can cosmogenic 10Be help to quantify the chronology of quarrying in this area? The aim of our study is therefore to first determine the extent of the working area of the Romans and then to date the
Abstracts / Quaternary International 279-280 (2012) 121–232
distribution. The progressive decline in the coercivity of the antiferromagnetic minerals in bulk samples throughout the whole period is mainly an expression of changes in the detrital fraction, reflecting changes in the source region, possibly involving increased aluminium substitution. The good correlation between DRS-defined hematite and frequency-dependent magnetic susceptibility in several chronologically defined subgroups of samples is consistent with the hypothesis that maghemite forms a transitional phase in a weathering sequence from ferrihydrite to hematite. The results shed new light on using HIRM to characterize hematite and goethite in sediments and on the history of weathering and climate change over the last 22 Ma in the dust source regions and on the Loess Plateau. THE DISTRIBUTION AND VULNERABILITIES OF CARBON IN PERMAFROST LANDSCAPES Jennifer Harden. U.S.Geological Survey, United States E-mail address: [email protected]
Carbon storage in northern landscapes reflects the climatic and environmental history under which C has accumulated. While the influence of temperature protects C from decomposition, water content and phase also regulate stabilization and destabilization of C on a variety of spatial scales: Topographic controls on solar insolation likely contribute to patterns of C storage with aspect and relief. Soil drainage affects moisture content and thermal properties, which interact to influence patterns of C storage with respect to combustion and vegetation. We have distinguished upland from lowland landscapes as separate pathways for regional warming to propagate through permafrost landscapes. In uplands, C becomes vulnerable mainly through top-down thaw and hillslope mobilization through surface and subsurface flow. In lowlands, permafrost C becomes vulnerable through thermokarst and lateral expansion of water bodies. Estimating C emissions from permafrost landscapes, however, requires both spatial and temporal components to account for different disturbance regimes, soil types, and permafrost characteristics. Here we explore key attributes of carbon, disturbance regime, landscape change, and feedbacks that must be quantified in order to estimate C emissions from degrading permafrost landscapes. SYNCHRONIZING HIGH-RESOLUTION POLLEN RECORDS FROM THE LAST GLACIAL (C.20-50 KA BP) USING TEPHROCHRONOLOGY: TESTING FOR ‘LEADS’ AND ‘LAGS’ DURING ENVIRONMENTAL TRANSITION Mark Hardiman. Centre for Quaternary Research, Department of Geog, United Kingdom E-mail address: [email protected]
Abrupt environmental transitions have been inferred from southern Europe based on multiple high resolution pollen records spanning the Last Glacial (c.20-50 Ka BP). These shifts have largely been related to Dansgaard-Oeschger cycles and Heinrich events. However, establishing the synchronicity, the ‘leads’ and ‘lags’, and regional variation of vegetation shifts is hampered by chronological uncertainties. Problems with the most commonly used technique, radiocarbon dating, include the old carbon effect in carbonate basins, lack of suitable sample material and calibration uncertainties, particularly for age estimates older than c.18 Ka BP. Due to these problems pollen stratigraphies are frequently aligned with other records. This procedure does not allow for the recognition of ‘leads’ and ‘lags’ in the environmental system and assumes that different proxies responded in a similar way to a common climatic forcing mechanism. Here we report on an approach that has the potential to overcome these difficulties. We present tephrochronological data from three sites in the eastern Mediterranean region– Kopais, Tenaghi Philippon and Lesvos. Some of the ash layers are non-visible ‘micro’ or ‘crypto’ tephras which have been assigned to volcanic source using both major, minor (EPMA) and trace element (LA-ICP-MS and SIMS) geochemical data from single shard analyses. Tephra layers correlated between sites can be used firstly to create a more precise ordering of palaeoenvironmental events and secondly to synchronise multiple records utilising Bayesian age-modelling techniques. The ability to use multiple tephra horizons to establish the relative phasing of vegetation changes across three terrestrial pollen sites
in the eastern Mediterranean region is fully explored; the chronological and palaeoenvironmental implications will be outlined. GEOCHRONOLOGICAL RECONSTRUCTION OF THE PLEISTOCENE FLUVIAL INCISION OF THE MOSELLE RIVER AND ITS MAIN TRIBUTARIES THE MEURTHE AND SARRE RIVERS (FRANCE, GERMANY) Dominique Harmand. Université Nancy 2, France E-mail address: [email protected]
The fluvial terrace sequence of the main rivers flowing through the Eastern Paris Basin and the western Rhenish Massif has been intensively studied during the last decade. The multi-proxy study included morphological, sedimentological and geochronological approaches. The latter was based both on ESR for the Marne and the Aisne catchments, and on OSL for the lower terraces of the Moselle River and its tributaries. This chronological framework has recently been complemented with the obtention of 15 ESR datings of fluvial sediments from the Upper and Lower Moselle, the Meurthe, and the Sarre rivers. These yielded ages ranging from 0.2 and 1.9 Ma. The age estimates make it possible to update the previous chronostratigraphical framework for the Moselle catchment and in particular to demonstrate that the so-called “main terrace complex” of the Mosel and Saar valleys corresponds with stepped terraces related to different aggradation periods during the Lower Pleistocene. The results also improve the knowledge of the fluvial response to glacial-interglacial cycles, and provide evidence for a more or less constant incision rate estimated at 10 cm.ka 1 both in the Eastern Paris Basin and the Rhenish Massif. QUATERNARY RECORDS OF THE CONTINENTAL SHELF AND LOWER COASTAL PLAIN, SOUTH CAROLINA (USA): EXAMPLES OF WELLPRESERVED STRATIGRAPHIC RECORD AND DISTINCT LANDSCAPES FROM MIS-5 TO THE PRESENT M. Scott Harris. College of Charleston, United States E-mail address: [email protected]
The Continental Shelf and Coastal Plain of the southeastern United States contain a superior record of emergent coastal barrier system strata and geomorphologies as well as a sparsely distributed, but well-preserved landscape on a sediment-starved shelf. This paper presents the current state of knowledge on the stratigraphic deposits and geomorphic landscape developed during the last interglacial (MIS-5), to the last glacial lowstand, to the current sea level and modern coastal barrier systems. A geological understanding of these Pleistocene and Holocene landscapes as related to coastal management, marine spatial planning, and essential fish habitats is the purpose of our studies in this region. Using multibeam bathymetry, sidescan sonar, high-resolution subbottom profiles, ground penetrating radar, and LiDAR surveys of the last glacial maximum (LGM) deposits on the edge of the continental shelf to the emerged MIS-5 coastal systems, we present high-resolution interpretations of a variety of coastal, marine, and terrestrial landscapes. MIS-5 deposits comprise wellpreserved transgressive and regressive coastal systems with abundant, weakly altered landforms. LGM deposits are represented by a definable set of near-surface reflectors at a consistent depth along the edge of the shelf below 120m. Younger-Dryas swamp deposits and tidal channels frequently cover the shelf between the 20m and 25m isobaths. Modern coastal systems range from short drumstick barriers with many inlets to headland-attached strand beaches. These extend seaward into a complex array of sand, shell, mud, and rocky deposits exposed and reworked on the active shoreface. Mapping and delineating this heterogeneous patchwork of unconsolidated sediment interspersed with rocky plains and ledges will continue to be a priority to coastal managers, fishery scientists, and marine spatial planners over the next two decades. SUBGLACIAL TILL BEHAVIOUR DERIVED FROM IN SITU WIRELESS MULTI-SENSOR SUBGLACIAL PROBES: RHEOLOGY, HYDROMECHANICAL INTERACTIONS AND TILL FORMATION Jane Hart. University of Southampton, United Kingdom E-mail address: [email protected]
Abstracts / Quaternary International 279-280 (2012) 121–232
189
The rheology and hydro-mechanical interactions at the ice-bed interface form an important component of the glacier system, influencing glacier dynamics and the formation of till. We demonstrate that the sand-rich tills at Briksdalsbreen in Norway and Skalafellsjökull, Iceland, undergo deformation throughout the year, but with different styles. On the bulk rheology scale, till deformation exhibits elastic behaviour during the winter, when water pressures are low; and linear viscous behaviour after a critical yield stress of 35 kPa, when water pressures are high during the spring and summer. On the clast and matrix scale, low water pressures, correspond with high case stress variability and till temperatures. Meltwater driven, stick-slip, glacier velocity increases were transmitted through a relatively strong till grain network, causing brittle deformation. Intermediate water pressures, during late summer were linked to intermediate case stress variability and high till temperatures associated with the heat generated from stick-slip motion. High water pressures in the till were associated with low case stress variability and low, meltwater controlled, till temperatures, and occurred in the spring and autumn. Once the till was saturated, the ductile till absorbed any stick-slip velocity increases. We discuss, with examples, the different till forming processes associated with these changing conditions, demonstrating that the resultant till will represent a complex amalgamation of all of these processes.
seawater. The model integrates hydrological, technological and economic considerations, and estimates the economic and environmental impacts of alternative water management policies; it was implemented in a case study in Israel. We constructed a unique hydrological database with data for each hydrological cell and applied a hydrological model for planning the allocation of the water resources and forecasting the concentration of chlorides in the aquifer under alternative scenarios. These scenarios included a variety of threshold policies for water supply. We developed an economic model that estimated the costs of various desalination processes, and calculated the costs of the water supply to the region under these scenarios. The hydrological model produces annual forecasts of chloride concentration in groundwater, while the economic model produces forecasts of the implementation costs. The conclusions from calculating the costs of improving the threshold chloride levels in the water supplies to city and/or agriculture or the steady-state levels in the aquifer are that desalination of brackish water involves the lowest costs, desalination of wastewater is significant for maintaining the chloride concentration threshold in water for agriculture, and desalination of seawater is recommended to maintain the national water balance. We conclude that the economic cost of improving the quality of the supplied water and of the aquifer water should be considered in decision making.
THE NEW LAKES – TERMINATION 1 COMPARED TO RECENT PROCESSES (IN SWISS ALPS AND A GLOBAL COMPARISON)
MAGNETIC FINGERPRINTING OF GREENLANDIC SEDIMENTS Robert Hatfield. Oregon State University, United States
Cédric Hartmann. University of Bern, Switzerland
E-mail address: rhatfi[email protected]
E-mail address: [email protected]
As is well-known from dating, fast deglaciation after the Last Glacial Maximum (LGM) caused glacial lakes as known as the Schweizer Alpenrandseen. By looking at these dates, recovered by 14C-Methode from unconsolidated sediment including organic matter deposited on top of till, it stands out that the ages of the dates from Swiss Foreland compared to the ones from the Alps are practical the same. This gives us the indication for an assumption that the enormous ice mass, which was distributed in most parts of Swiss Foreland, melted down and the glaciers retreated to the inneralpine passes in a very short time phase. In present days in alpine area deglaciation is proceeding fast again and is producing sub-, supra- or proglacial lakes. Not much is known about genesis of glacier lakes or better why the Swiss Lakes never have been filled up with sediments as in normal case while glacial retreat? And how it looks like globally? Do we have the same phenomena there? So we try to compare foreign literature with following analysis. We attempt to give an overview on the topic glacial lake and ask the question if there are parallels from the paleo- to the presentsituation? It is a challenge to display the comparison of these two time sequences and to reveal basic phenomena what these lakes are. For that we use features like different kind of maps, profiles and pictures from the last 10 to 20 years to get a better overview and then compare it to literature. But also mapping of the investigation areas, Trift-, Unteraar- and Rhône-Glacier should give us further information for the studies. The mentioned areas are chosen by following criteria: There is a significant retreat of the glacier in present time, they are all producing lake systems on or in front of the glacier in last decades and they bring different preconditions (steepness, underground, wide-ness of valley, etc.) with. Further investigations will be done till fall 2011 to clarify those problems and open questions. A MODEL FOR INTEGRATED WATER RESOURCES MANAGEMENT IN WATER-SCARCE REGIONS: MINIMIZATION OF THE IMPACTS OF GROUNDWATER EXPLOITATION ON SOCIETY AND THE ENVIRONMENT
In principle the geologic record of previous Greenland Ice Sheet (GIS) deglaciations can provide a context from which to assess present and future behaviors. The question is how to accurately trace ice sheet retreat for times when no terrestrial evidence remains. The marine record records these past variation, but deconvolving the integrated signal into ice sheet behavior is a non-trivial problem. By developing sediment fingerprints it may be possible to trace sediment export and determine when specific areas of Greenland became ice-free. A precursor to any such approach is the establishment of a comprehensive dataset that characterizes and discriminates between potential sources so that robust fingerprints can be constructed. Here we present particle-size magnetic data from sediments collected from the three main geological terranes of southern Greenland and basalts from Iceland. Samples were split into six particle size fractions with magnetic susceptibility showing the magnetic signal to be dominantly carried in the medium-fine silt fractions (45-10 mm) of the sediments. Significant intra-fraction variation within samples means that apparent discrimination based on measurement of bulk sediments could reflect grain-size variations rather than geological diversity; thus fingerprints should only be constructed on a particle size basis. Initial particlesize specific magnetic remanence results show magnetic similarities within terranes and variation between magnetic terranes, replicable over several particle size fractions. Comparison of these terrestrial fingerprints to oceanic cores through events when GIS mass wasting was highest (i.e. glacial terminations) should allow estimation of the relative amounts of sediment export from Greenland's three terranes; linked to the geographical extent of the GIS. These fingerprints can also aid understanding of other processes operating proximally to the GIS; e.g. the strength of the WBUC and/or understanding of IRD sources. COSMOGENIC 10BE EXPOSURE DATING OF ANCIENT QUARRIES IN WESTERN TURKEY Esther Haudenschild. Institut für Geologie, Switzerland E-mail address: [email protected]
Nava Haruvy. Netanya Academic College, Israel E-mail address: [email protected]
Israel as a water scarce country increased its exploitation of groundwater resources, which has caused problems of local aquifer contamination. Urban development and adoption of water desalination and irrigation with wastewater accelerate groundwater salinity and climatic change will further exacerbate these problems. We developed a model for planning water supply from diverse sources, including groundwater wastewater and
Kestanbol Granite, outcropping in the Ezine village of Çanakkale, was operated by the Romans for the production and export of building stones since ancient times. Today, remnant building stones can still be found in the ruins of these quarries, whose extent and operation periods are unknown, although archaeologists roughly estimate a Roman period from 500 BC to 500 AD. Can cosmogenic 10Be help to quantify the chronology of quarrying in this area? The aim of our study is therefore to first determine the extent of the working area of the Romans and then to date the