- Email: [email protected]
Investigating diverse phenomena of slope movement in mountain areas
Abstracts / Quaternary International 279-280 (2012) 462–565
INVESTIGATING DIVERSE PHENOMENA OF SLOPE MOVEMENT IN MOUNTAIN AREAS Vanessa Wirz. Universität Zürich, Switzerland E-mail address: [email protected]
Permafrost is sensitive to climate change and its degradation can newly develop or accelerate slope instabilities. Previous studies mostly concentrated on rock glacier dynamics and rock wall stabilities. In the last few decades, an increasing number of rock falls in permafrost slopes and increasing creep rates of rock glaciers were observed. Within X-Sense, a joint project between different research groups (Geodesy, Computer engineering and Geography) the aim is to develop and deploy instruments and methods to continuously measure the dynamics of permafrost slopes using differential GPS (Global Positioning System) surveys and interferomertric synthetic aperture radar (InSAR) data. The objective of the presented study is (a) to give an overview of the differing types of slope movement in mountain permafrost, (b) to develop research strategies and methods to analyze seasonal and inter-annual velocity variations and (c) to develop hypotheses on the influencing factors. The field area (Matter valley, Switzerland) includes exceptionally fast and potentially hazardous rock glaciers (moving up to 30 m/a) as well as slopes where clear evidence for movement exists but the underlying mechanisms remain unknown. We present research strategies and methods to investigate displacement time series in permafrost slopes based on continuous GPS observations and InSAR data. Due to the high temporal resolution of the GPS data and the high spatial coverage of the InSAR data, process-oriented studies can be applied to analyze the influence of important factors. ON THE PERIPHERY OF THE MAGDALENIAN WORLD. AN OPEN-AIR SITE IN KLEMENTOWICE (E POLAND) Tadeusz Wisniewski. Maria Curie Sklodowska University, Poland E-mail address: [email protected]
Klementowice village is located in the western part of the Na1eczów Plateau in the north-west part of the Lublin Upland. The site is located on a mild slope of a loess patch in the upper part of a small water-course called the Klementowice Stream. The site in Klementowice was discovered in 1981 and the same year and in 1982 excavations were conducted by S. Jastrzebski and J. Libera, during which over 7 382 items were discovered. They were mainly flint artefacts and fragments of stone tiles. Numerous artefacts, especially tools (10% of all), allowed finding analogies to materials found in Moravia and Germany. On the basis of characteristic tool forms, the authors of the excavations date the entire assemblage to the end of the Bulling Interstadial and associate it with the Late Magdalenian Culture. After 1982, the excavations were stopped. Only 25 years later, in 2007, the excavations were resumed and conducted by T. Wisniewski. During the field works, a new unknown concentrations of flint artefacts was discovered. In total, some 3 000 artifacts were obtained, including 250 tools. Perforators and burins dominate among the tools, including those of the Lacan type which were not recorded earlier in the inventory. During 2010 archaeological investigation the flint inventory was supplemented by remains of fauna, first from the site. They are pieces of horse's teeth as well as a fragment of horse's jaw, rib and long bones. Good state of preserve of the bones, especially teeth allowed to perform multidimensional analysis. We'll also be able to determine the age of the site by making radiocarbon dating. Klementowice, at the same time, is the furthest Magdalenian settlement point to the north-east, not only in Poland but also in the whole Europe. HOLOCENE FLUVIAL DYNAMICS OF THE GUADALETE RIVER (SWANDALUSIA) Daniel Wolf. Technical University, Germany E-mail address: [email protected]
The river Guadalete runs through the southwestern part of Andalusia (Spain) with its river head being located in the heights of the Sierra de Grazalema. On its course into the Bahia de Cádiz, the Guadalete passes a landscape of high sensitivity. Because of steep gradients in the headwater
539
and several constructions of water reservoirs along the upper course, only the lower reaches of the river are suitable to reconstruct Holocene river history. Fluvial architecture is quite complex and shows phases of river aggredation, river stability including features of soil formation inside the sediment and phases of incision as well. However, fluvial behavior and resulting sediment characteristics are likewise dependent on valley geometry, varying from narrow sections to wide valley floors. Particular landscape sensitivity is expressed by local tectonic activity primarily forced by the tilting of marly Keuper substratum, as well as by high erodibility of the surrounding marl landscape, which underlies an intense land use. Several profile analyses of gravel pits and corings enabled us to compile a standard profile, which provides information about the Holocene river history. In our presentation we attempt to describe causes and effects of different sedimentation patterns, while providing them with a chronological framework. ASSESSING FORMALDEHYDE AS A TOOL FOR SYNCHRONISING ICE AND GAS RECORDS IN ANTARCTIC ICE CORES Eric Wolff. British Antarctic Survey, United Kingdom E-mail address: [email protected]
Understanding terminations and millennial scale changes requires an excellent knowledge of the sequence of events that occurred. For ice cores, a precise understanding is hampered because the climate response is observed in the ice phase, but the gases (such as CO2) are in the air bubbles. The key to synchronising these datasets is to precisely determine the difference in age between ice and air at the same depth or the difference in depth between data of the same age (delta-depth). In Antarctica, the climate changes are too slow for direct use of the 15N signal of rapid warming used in Greenland. However if a signal in the ice phase corresponding to the rapid methane rise of each Dansgaard-Oeschger event could be found, then numerous synchronisation points could be established. Formaldehyde (HCHO) is an oxidation product of methane. Its use in ice cores has been restricted by very strong postdepositional losses, making it more dependent on climate than on atmospheric chemistry. At sites with low accumulation rate, most HCHO is lost, making even its detection questionable. Nonetheless, at ice depths corresponding to the fast methane rises, Antarctic climate is rather constant (across the apex of an Antarctic Isotopic Maximum). Any residual HCHO signal at these depths should consist of a slowly changing concentration (due to the smoothly varying climate), with a net jump in concentrations at the age where methane jumps. Here we will measure, with the most sensitive methods, the residual HCHO signal across one or more of these events in 2 Antarctic ice cores as a proof of concept for this method of synchronising ice cores. We will present our results, to establish whether or not the expected signal can be identified. If we are successful in identifying the depth of such a HCHO jump, then it opens up a new, well-understood method to pin delta-depth along Antarctic cores, and thus define precisely the timing between changes in climate and in (e.g.) CO2. CLIMATIC HISTORY OF THE PAST 2,000 YEARS RECORDED IN THE THREE STALAGMITES FROM THE YONGCHEON AND DANGCHEOMUL LAVA TUBE CAVES IN JEJU ISLAND, SOUTH KOREA Kyung-Sik Woo. Kanwon National University, Korea E-mail address: [email protected]
Yongcheon and Dangcheomul Caves are located on Jeju Island, the southernmost part of Korea. The island is under the strong influence of East Asian monsoon climate. Even though the Yongcheon and Dangcheomul caves are typical lava tube caves which probably formed between 0.2w0.4 Ma ago, they contain numerous carbonate speleothems which is less than a few thousand years old. Presence of carbonate speleothems is the result of overlying carbonate sand dunes which were formed by the transport of carbonate sands onto the cave from nearby beaches. Three stalagmites (YC1, YC-2 and DC-1) were collected in their growth position in 2005, 2008 and 2010, respectively. The ages of the stalagmites were determined by 210Pb dating, radiocarbon dating and U/Th dating and by counting growth laminae. Age dating revealed that the ages of stalagmites range from 300 years to 3,000 years. High resolution stable isotope analyses were carried out. The YC-1 clearly shows Dark Age Cold Period, Medieval Warm Period,
INVESTIGATING DIVERSE PHENOMENA OF SLOPE MOVEMENT IN MOUNTAIN AREAS Vanessa Wirz. Universität Zürich, Switzerland E-mail address: [email protected]
Permafrost is sensitive to climate change and its degradation can newly develop or accelerate slope instabilities. Previous studies mostly concentrated on rock glacier dynamics and rock wall stabilities. In the last few decades, an increasing number of rock falls in permafrost slopes and increasing creep rates of rock glaciers were observed. Within X-Sense, a joint project between different research groups (Geodesy, Computer engineering and Geography) the aim is to develop and deploy instruments and methods to continuously measure the dynamics of permafrost slopes using differential GPS (Global Positioning System) surveys and interferomertric synthetic aperture radar (InSAR) data. The objective of the presented study is (a) to give an overview of the differing types of slope movement in mountain permafrost, (b) to develop research strategies and methods to analyze seasonal and inter-annual velocity variations and (c) to develop hypotheses on the influencing factors. The field area (Matter valley, Switzerland) includes exceptionally fast and potentially hazardous rock glaciers (moving up to 30 m/a) as well as slopes where clear evidence for movement exists but the underlying mechanisms remain unknown. We present research strategies and methods to investigate displacement time series in permafrost slopes based on continuous GPS observations and InSAR data. Due to the high temporal resolution of the GPS data and the high spatial coverage of the InSAR data, process-oriented studies can be applied to analyze the influence of important factors. ON THE PERIPHERY OF THE MAGDALENIAN WORLD. AN OPEN-AIR SITE IN KLEMENTOWICE (E POLAND) Tadeusz Wisniewski. Maria Curie Sklodowska University, Poland E-mail address: [email protected]
Klementowice village is located in the western part of the Na1eczów Plateau in the north-west part of the Lublin Upland. The site is located on a mild slope of a loess patch in the upper part of a small water-course called the Klementowice Stream. The site in Klementowice was discovered in 1981 and the same year and in 1982 excavations were conducted by S. Jastrzebski and J. Libera, during which over 7 382 items were discovered. They were mainly flint artefacts and fragments of stone tiles. Numerous artefacts, especially tools (10% of all), allowed finding analogies to materials found in Moravia and Germany. On the basis of characteristic tool forms, the authors of the excavations date the entire assemblage to the end of the Bulling Interstadial and associate it with the Late Magdalenian Culture. After 1982, the excavations were stopped. Only 25 years later, in 2007, the excavations were resumed and conducted by T. Wisniewski. During the field works, a new unknown concentrations of flint artefacts was discovered. In total, some 3 000 artifacts were obtained, including 250 tools. Perforators and burins dominate among the tools, including those of the Lacan type which were not recorded earlier in the inventory. During 2010 archaeological investigation the flint inventory was supplemented by remains of fauna, first from the site. They are pieces of horse's teeth as well as a fragment of horse's jaw, rib and long bones. Good state of preserve of the bones, especially teeth allowed to perform multidimensional analysis. We'll also be able to determine the age of the site by making radiocarbon dating. Klementowice, at the same time, is the furthest Magdalenian settlement point to the north-east, not only in Poland but also in the whole Europe. HOLOCENE FLUVIAL DYNAMICS OF THE GUADALETE RIVER (SWANDALUSIA) Daniel Wolf. Technical University, Germany E-mail address: [email protected]
The river Guadalete runs through the southwestern part of Andalusia (Spain) with its river head being located in the heights of the Sierra de Grazalema. On its course into the Bahia de Cádiz, the Guadalete passes a landscape of high sensitivity. Because of steep gradients in the headwater
539
and several constructions of water reservoirs along the upper course, only the lower reaches of the river are suitable to reconstruct Holocene river history. Fluvial architecture is quite complex and shows phases of river aggredation, river stability including features of soil formation inside the sediment and phases of incision as well. However, fluvial behavior and resulting sediment characteristics are likewise dependent on valley geometry, varying from narrow sections to wide valley floors. Particular landscape sensitivity is expressed by local tectonic activity primarily forced by the tilting of marly Keuper substratum, as well as by high erodibility of the surrounding marl landscape, which underlies an intense land use. Several profile analyses of gravel pits and corings enabled us to compile a standard profile, which provides information about the Holocene river history. In our presentation we attempt to describe causes and effects of different sedimentation patterns, while providing them with a chronological framework. ASSESSING FORMALDEHYDE AS A TOOL FOR SYNCHRONISING ICE AND GAS RECORDS IN ANTARCTIC ICE CORES Eric Wolff. British Antarctic Survey, United Kingdom E-mail address: [email protected]
Understanding terminations and millennial scale changes requires an excellent knowledge of the sequence of events that occurred. For ice cores, a precise understanding is hampered because the climate response is observed in the ice phase, but the gases (such as CO2) are in the air bubbles. The key to synchronising these datasets is to precisely determine the difference in age between ice and air at the same depth or the difference in depth between data of the same age (delta-depth). In Antarctica, the climate changes are too slow for direct use of the 15N signal of rapid warming used in Greenland. However if a signal in the ice phase corresponding to the rapid methane rise of each Dansgaard-Oeschger event could be found, then numerous synchronisation points could be established. Formaldehyde (HCHO) is an oxidation product of methane. Its use in ice cores has been restricted by very strong postdepositional losses, making it more dependent on climate than on atmospheric chemistry. At sites with low accumulation rate, most HCHO is lost, making even its detection questionable. Nonetheless, at ice depths corresponding to the fast methane rises, Antarctic climate is rather constant (across the apex of an Antarctic Isotopic Maximum). Any residual HCHO signal at these depths should consist of a slowly changing concentration (due to the smoothly varying climate), with a net jump in concentrations at the age where methane jumps. Here we will measure, with the most sensitive methods, the residual HCHO signal across one or more of these events in 2 Antarctic ice cores as a proof of concept for this method of synchronising ice cores. We will present our results, to establish whether or not the expected signal can be identified. If we are successful in identifying the depth of such a HCHO jump, then it opens up a new, well-understood method to pin delta-depth along Antarctic cores, and thus define precisely the timing between changes in climate and in (e.g.) CO2. CLIMATIC HISTORY OF THE PAST 2,000 YEARS RECORDED IN THE THREE STALAGMITES FROM THE YONGCHEON AND DANGCHEOMUL LAVA TUBE CAVES IN JEJU ISLAND, SOUTH KOREA Kyung-Sik Woo. Kanwon National University, Korea E-mail address: [email protected]
Yongcheon and Dangcheomul Caves are located on Jeju Island, the southernmost part of Korea. The island is under the strong influence of East Asian monsoon climate. Even though the Yongcheon and Dangcheomul caves are typical lava tube caves which probably formed between 0.2w0.4 Ma ago, they contain numerous carbonate speleothems which is less than a few thousand years old. Presence of carbonate speleothems is the result of overlying carbonate sand dunes which were formed by the transport of carbonate sands onto the cave from nearby beaches. Three stalagmites (YC1, YC-2 and DC-1) were collected in their growth position in 2005, 2008 and 2010, respectively. The ages of the stalagmites were determined by 210Pb dating, radiocarbon dating and U/Th dating and by counting growth laminae. Age dating revealed that the ages of stalagmites range from 300 years to 3,000 years. High resolution stable isotope analyses were carried out. The YC-1 clearly shows Dark Age Cold Period, Medieval Warm Period,