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Статті в журналах з теми "Last glaciation (MIS3 à 2)"
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Liakka, J., M. Löfverström, and F. Colleoni. "The impact of the North American ice sheet on the evolution of the Eurasian ice sheet during the last glacial cycle." Climate of the Past Discussions 11, no. 6 (2015): 5203–41. http://dx.doi.org/10.5194/cpd-11-5203-2015.
Повний текст джерелаАнотація:
Abstract. Modeling studies show that the massive ice sheet expanding over the North American and Eurasian continents in the last glacial cycle has a large impact on the atmospheric stationary waves and thus yielded a glacial climate distinctly different from the present. However, to what extent the two ice sheets influenced each others growth trajectories remains largely unexplored. In this study we investigate how ice sheets in North America influence the downstream evolution of the Eurasian ice sheet, using a thermomechanical ice-sheet model forced by climate data from snapshot simulations of three distinctly different phases of the last glacial cycle: the Marine Isotope Stages 5b, 4 and 2 (LGM). Our results suggest that changes in the North American paleo-topography may have had a large influence on evolution of the Eurasian ice sheet. In the MIS4 and LGM experiments, the Eurasian ice sheet migrates westward towards the Atlantic sector – largely consistent with geological data and contemporary ice-sheet reconstructions – due to a low wavenumber stationary wave response, which yields a cooling in Europe and a warming in northeastern Siberia. The expansion of the North American ice sheet between MIS4 and LGM amplifies the Siberian warm anomaly, which limits the glaciation there and may therefore help to explain the progressive westward migration of the Eurasian ice sheet over this time period. While the Eurasian ice sheet in the MIS4 and LGM experiments appears to be in equilibrium with the simulated climate conditions, the MIS5b climate forcing is too warm to grow an ice sheet. First-order sensitivity experiments suggest that most of the MIS5b ice sheet was established during preceding colder stages.
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Liakka, Johan, Marcus Löfverström, and Florence Colleoni. "The impact of the North American glacial topography on the evolution of the Eurasian ice sheet over the last glacial cycle." Climate of the Past 12, no. 5 (2016): 1225–41. http://dx.doi.org/10.5194/cp-12-1225-2016.
Повний текст джерелаАнотація:
Abstract. Modeling studies have shown that the continental-scale ice sheets in North America and Eurasia in the last glacial cycle had a large influence on the atmospheric circulation and thus yielded a climate distinctly different from the present. However, to what extent the two ice sheets influenced each others' growth trajectories remains largely unexplored. In this study we investigate how an ice sheet in North America influences the downstream evolution of the Eurasian ice sheet, using a thermomechanical ice-sheet model forced by climate data from atmospheric snapshot experiments of three distinctly different phases of the last glacial cycle: the Marine Isotope Stages 5b, 4, and 2 (Last Glacial Maximum – LGM). Owing to the large uncertainty associated with glacial changes in the Atlantic meridional overturning circulation, each atmospheric snapshot experiment was conducted using two distinctly different ocean heat transport representations. Our results suggest that changes in the North American paleo-topography may have largely controlled the zonal distribution of the Eurasian ice sheet. In the MIS4 and LGM experiments, the Eurasian ice sheet migrates westward towards the Atlantic sector – largely consistent with geological data and contemporary ice-sheet reconstructions – due to a low wave number stationary wave response, which yields a cooling in Europe and a warming in northeastern Siberia. The expansion of the North American ice sheet between MIS4 and the LGM amplifies the Siberian warm anomaly, which limits the glaciation there and may therefore help explain the progressive westward migration of the Eurasian ice sheet in this time period. The ocean heat transport only has a small influence on the stationary wave response to the North American glacial topography; however, because temperature anomalies have a smaller influence on an ice sheet's ablation in a colder climate than in a warmer one, the impact of the North American glacial topography on the Eurasian ice-sheet evolution is reduced for colder surface conditions in the North Atlantic. While the Eurasian ice sheet in the MIS4 and the LGM experiments appears to be in equilibrium with the simulated climate conditions, the MIS5b climate forcing is too warm to grow an ice sheet in Eurasia. First-order sensitivity experiments suggest that the MIS5b ice sheet was established during preceding colder stages.
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Van Meerbeeck, C. J., H. Renssen, and D. M. Roche. "How did Marine Isotope Stage 3 and Last Glacial Maximum climates differ? Perspectives from equilibrium simulations." Climate of the Past Discussions 4, no. 5 (2008): 1115–58. http://dx.doi.org/10.5194/cpd-4-1115-2008.
Повний текст джерелаАнотація:
Abstract. Dansgaard-Oeschger events occurred frequently during Marine Isotope Stage 3 (MIS3), as opposed to the following MIS2 period, which included the Last Glacial Maximum (LGM). Transient climate model simulations suggest that these abrupt warming events in Greenland and the North Atlantic region are associated with a resumption of the Thermohaline Circulation (THC) from a weak state during stadials to a relatively strong state during interstadials. However, those models were run with LGM, rather than MIS3 boundary conditions. To quantify the influence of different boundary conditions on the climates of MIS3 and LGM, we perform two equilibrium climate simulations with the three-dimensional earth system model LOVECLIM, one for stadial, the other for interstadial conditions. We compare them to the LGM state simulated with the same model. Both climate states are globally 2°C warmer than LGM. A striking feature of our MIS3 simulations is the enhanced Northern Hemisphere seasonality, July being 4°C warmer than in LGM. Also, despite some modification in the location of North Atlantic deep water formation, deep water export to the South Atlantic remains unaffected. To study specifically the effect of orbital forcing, we perform two additional sensitivity experiments spun up from our stadial simulation. The insolation difference between MIS3 and LGM causes half of the 30–60°N July temperature anomaly (+6°C). In a third simulation additional freshwater forcing halts the Atlantic THC, yielding a much colder North Atlantic region (−7°C). Comparing our simulation with proxy data, we find that the MIS3 climate with collapsed THC mimics stadials over the North Atlantic better than both control experiments, which might crudely estimate interstadial climate. These results suggest that freshwater forcing is necessary to return climate from warm interstadials to cold stadials during MIS3. This changes our perspective, making the stadial climate a perturbed climate state rather than a typical, near-equilibrium MIS3 climate.
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Van Meerbeeck, C. J., H. Renssen, and D. M. Roche. "How did Marine Isotope Stage 3 and Last Glacial Maximum climates differ? – Perspectives from equilibrium simulations." Climate of the Past 5, no. 1 (2009): 33–51. http://dx.doi.org/10.5194/cp-5-33-2009.
Повний текст джерелаАнотація:
Abstract. Dansgaard-Oeschger events occurred frequently during Marine Isotope Stage 3 (MIS3), as opposed to the following MIS2 period, which included the Last Glacial Maximum (LGM). Transient climate model simulations suggest that these abrupt warming events in Greenland and the North Atlantic region are associated with a resumption of the Thermohaline Circulation (THC) from a weak state during stadials to a relatively strong state during interstadials. However, those models were run with LGM, rather than MIS3 boundary conditions. To quantify the influence of different boundary conditions on the climates of MIS3 and LGM, we perform two equilibrium climate simulations with the three-dimensional earth system model LOVECLIM, one for stadial, the other for interstadial conditions. We compare them to the LGM state simulated with the same model. Both climate states are globally 2°C warmer than LGM. A striking feature of our MIS3 simulations is the enhanced Northern Hemisphere seasonality, July surface air temperatures being 4°C warmer than in LGM. Also, despite some modification in the location of North Atlantic deep water formation, deep water export to the South Atlantic remains unaffected. To study specifically the effect of orbital forcing, we perform two additional sensitivity experiments spun up from our stadial simulation. The insolation difference between MIS3 and LGM causes half of the 30–60° N July temperature anomaly (+6°C). In a third simulation additional freshwater forcing halts the Atlantic THC, yielding a much colder North Atlantic region (−7°C). Comparing our simulation with proxy data, we find that the MIS3 climate with collapsed THC mimics stadials over the North Atlantic better than both control experiments, which might crudely estimate interstadial climate. These results suggest that freshwater forcing is necessary to return climate from warm interstadials to cold stadials during MIS3. This changes our perspective, making the stadial climate a perturbed climate state rather than a typical, near-equilibrium MIS3 climate.
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Ploskov, A. N., A. V. Eliseev, and I. I. Mokhov. "ENSEMBLE MODELLING OF ICE SHEET DYNAMICS IN THE LAST GLACIAL CYCLE." Доклады Российской академии наук. Науки о Земле 510, no. 1 (2023): 99–105. http://dx.doi.org/10.31857/s2686739722602873.
Повний текст джерелаАнотація:
Ensemble simulations (taking into account uncertainty of paleoclimate reconstructions) with a models for ice sheets dynamics for the last glacial cycle (last 128 kyr) are carried out. The model realistically reproduces spatial structure of major ice sheets and heights of their domes in the Northern hemisphere as well as the associated changes in global sea level. Perturbations with a sufficiently large amplitude applied to the initial paleoreconstruction result in marked differences of the modelling, in particular, durimg the Last Glacial maximu and during 58–51 kyr before present (the initial part of MIS3). According to our simualtions, the uncertainty of temperature reconstructions durng the last galcial cycle is limited to 2°C in agreement with existing estimates.
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Zolnikov, I. D., I. C. Novikov, E. V. Deev, A. V. Panin, and R. N. Kurbanov. "The Last Glaciation and Ice-Dammed Lakes in the South-East Altai." Journal "Ice and snow" 63, no. 4 (2023): 639–51. http://dx.doi.org/10.31857/s207667342304018x.
Повний текст джерелаАнотація:
Received June 8, 2023; revised September 4, 2023; accepted October 2, 2023The palaeogeographic scheme of the distribution of glaciers and ice-dammed lakes in the Altai during the last global glaciation (MIS-2) was compiled based on a detailed large-scale geomorphological survey. Analysis of geomorphological traces of glaciers of this time indicates that they occupied smaller areas than those of the first Late Pleistocene glaciation. By this means, the ice dams created by them were smaller that resulted in small sizes of ice-dammed lakes. The preserved levels of terraces indicate that during the first Late Pleistocene glaciation in the Kurai-Chuya depression system the ancient lake was the only one with a level of 2250 m and a total volume of 1.70 km3. During the second Late Pleistocene glaciation in the south-east Gorny Altai, another separate lake existed which was the Bartal-Kurai Lake with a level of 1700 m and a volume of 45 km3. This lake was dammed by the Mashey Glacier, which descended from the northern slopes of the North Chuaya Range. In the Chuya Depression, the existence of a landslide-dammed lake with a volume of 0.7 km3 and a level 1.750 m has been found. Its formation was not associated with glaciers of the MIS-2 stage. Direct dating of the last ice-dammed lake in the Chuya Depression with a level of 1950 m and a volume of 140 km3 has not yet been determined. This lake was dammed by the Kuehtanar Glacier, which descended from the southern slope of the Kurai ridge. The volume of ice-dammed waters of the MIS-2 time was an order of magnitude smaller than it was in the first Late Quaternary glaciation. This explains the much lower intensity of erosive and accumulative processes associated with the mega-flood occurred due to the breakthrough of the lakes during MIS-2.
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Lian, Olav B., and Stephen R. Hicock. "Lithostratigraphy and limiting optical ages of the Pleistocene fill in Fraser River valley near Clinton, south-central British Columbia." Canadian Journal of Earth Sciences 38, no. 5 (2001): 839–50. http://dx.doi.org/10.1139/e00-103.
Повний текст джерелаАнотація:
The Fraser River valley near Clinton contains a thick sediment fill that is presently incised down to bedrock. The sequence, approximately 500 m thick, is generally upward fining and consists of up to 100 m of glacigenic debris flow diamicton and glaciofluvialdeltaic gravel and sand at the base, overlain by about 350 m of glaciolacustrine sediments and minor diamicton, which is in turn capped by several metres of till. The sequence is interpreted to represent (i) valley aggradation in response to glaciation, followed by (ii) the impoundment of the valley by sediment and (or) ice, and the formation of a large proglacial lake(s), and finally (iii) overriding of the valley fill by glaciers. This glacial advance sequence can be readily correlated with previously studied units situated immediately to the north, most of which have been associated with the last glaciation; however, the age of these units has been based only on stratigraphic relations. We introduce limiting optical ages from a widespread glaciolacustrine unit that show that the glacial advance sequence was formed, at the earliest, during the penultimate Okanagan Centre Glaciation (oxygen isotope stage 4; ca. 7459 ka), but almost certainly during the (last) Fraser Glaciation (oxygen isotope stage 2; ca. 2412 ka). It could not have been deposited during oxygen isotope stage 6, or during an older glaciation.
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Lehmkuhl, Frank, Michael Klinge, Henrik Rother, and Daniela Hülle. "Distribution and timing of Holocene and late Pleistocene glacier fluctuations in western Mongolia." Annals of Glaciology 57, no. 71 (2016): 169–78. http://dx.doi.org/10.3189/2016aog71a030.
Повний текст джерелаАнотація:
Abstract.Despite being a key location for paleoglaciological research in north-central Asia, with the largest number of modern and Pleistocene glaciers, and in the transition zone between the humid Russian Altai and dry Gobi Altai, little is known about the precise extent and timing of Holocene and late Pleistocene glaciations in western Mongolia. Here we present detailed information on the distribution of modern and late Holocene glaciers, and new results addressing the geomorphological differentiation and numerical dating (by optically stimulated luminescence, OSL) of Pleistocene glacial sequences in these areas. For the Mongolian Altai, geochronological results suggest large ice advances correlative to marine isotope stages (MIS) 4 and 2. This is in contrast to results from the Khangai mountains, central Mongolia, showing that significant ice advances additionally occurred during MIS3. During the Pleistocene, glacial equilibrium-line altitudes (ELAs) were ~500 to >1000m lower in the more humid portion of the Russian and western Mongolian Altai, compared to 300-600 m in the drier ranges of the eastern Mongolian Altai. Pleistocene ELAs in the Khangai mountains were depressed by 700-1000 m, suggesting more humid conditions at times of major glaciation than in the eastern Mongolian Altai. This paleo-ELA pattern reveals that the precipitation gradient from the drier to the more humid regions was more pronounced during glacial times than at present.
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Glushkova, O. Yu, та V. N. Smirnov. "Реконструкция масштабов и морфологических особенностей плейстоценовых оледенений на Северо-Востоке России". Bulletin of the North-East Science Center, № 2 (30 червня 2021): 50–67. http://dx.doi.org/10.34078/1814-0998-2021-2-50-67.
Повний текст джерелаАнотація:
Based on the currently available data, it has been established that the earliest glaciations occurred in the Late Eopleistocene and at the end of the Early Neopleistocene. They had local distribution in the most uplifted parts of the Chersky Range. Their traces are presented in the form of moraines enclosed in sediments of intermontain depressions. Glacial forms of this age have not been identified in the relief of mountains and plains in the North-East of Russia. The Middle Neopleistocene glaciation was the largest, both in area and length of individual glaciers. It was mountain-valley and reticulated; in some areas, mountain-cover. Its time coincides with the stage of activation of the ascending neotectonic movements in the Middle Neopleistocene. Traces of the last two Late Neopleistocene glaciations are well expressed in the relief in widespread exaration, moraine, and fluvioglacial complexes. The first Late Neopleistocene glaciation (Zyryan) was significantly inferior to the one occurred in the Middle Neopleistocene, in all parameters, but it also left large amphitheaters of terminal moraines in the foothill belts. Glacial complexes of the last Late Neopleistocene glaciation are widespread in areas 2-3 times smaller than the previous one and, as a rule, are located within its contours.
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Shulmeister, James, Glenn D. Thackray, Tammy M. Rittenour, and Olivia M. Hyatt. "Multiple glacial advances in the Rangitata Valley, South Island, New Zealand, imply roles for Southern Hemisphere westerlies and summer insolation in MIS 3 glacial advances." Quaternary Research 89, no. 2 (2018): 375–93. http://dx.doi.org/10.1017/qua.2017.108.
Повний текст джерелаАнотація:
AbstractStratigraphic evidence and extensive optically stimulated luminescence (OSL) geochronology from an 18-km-long reach of the middle Rangitata Valley, South Island, New Zealand, provide evidence for at least six distinct glacial advances during the last glacial cycle. These include four well-constrained Marine Oxygen Isotope Stage (MIS) 3 and 2 advances at ca. 38 ka, ca. 27 ka, ca. 21 ka and at 18 ka, as well as less well-constrained advances in MIS 4 and/or early MIS 3. Ice occupied a farther downvalley reach of the Rangitata from 38 ka to after 18 ka, indicating that near-full glacial conditions persisted for most of the last 20 ka of the last glaciation, though the glacier still fluctuated significantly, as reflected by the numerous distinguishable advances. Global or regional cooling alone cannot explain the persistence of near-maximum glacial conditions for this extended period, nor can it explain the occurrence of the largest advances ca. 32 ka. Instead, we invoke the northward expansion of the westerlies during MIS 3 as the cause for the early widespread glaciation, wherein enhanced westerly flow under moderate cooling maximised glacial extents. Local insolation favoured extended MIS 3 glaciation until ca. 32 ka. Increasing summer insolation gradually reduced glacial extents after ca. 28 ka.
Дисертації з теми "Last glaciation (MIS3 à 2)"
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Pallier, Céline. "De l’enregistrement sédimentaire en milieu karstique à la taphonomie des sites archéologiques du Paléolithique supérieur (MIS 3-MIS 2) : les apports de la grotte du Mas d’Azil et de la vallée de l’Arize (Pyrénées, France)." Electronic Thesis or Diss., Toulouse 2, 2021. http://www.theses.fr/2021TOU20011.
Повний текст джерелаАнотація:
La grotte du Mas d’Azil, traversée par l’Arize, a conservé les témoignages de dynamiques hydrosédimentaires du dernier cycle glaciaire, qui ont conditionné à la fois les occupations humaines durant le Paléolithique supérieur et la conservation des vestiges archéologiques. Ainsi, comment l’étude d’un tel enregistreur sédimentaire peut-elle répondre à la question des lacunes archéologiques de la dernière période glaciaire ?Des hiatus, chronologiques ou d’ordre spatial, sont observés dans les occupations de la grotte. Quelle signification leur attribuer : absence des humains ou conservation différentielle ? A la transition MIS 3-MIS 2, une phase d’aggradation sédimentaire a contraint l’occupation dans la grotte, tout en jouant un rôle majeur dans la conservation ou l’érosion des vestiges. Elle a permis la conservation partielle des niveaux aurignaciens qu’elle recouvre, mais a rendu la grotte inaccessible pendant plusieurs millénaires. Enfin, l’étude géomorphologique permet une réflexion très précise sur l’organisation de l’espace, les accès et les circulations des populations à l’intérieur de la grotte au cours du Magdalénien moyen récent.La grotte renseigne aussi sur les dynamiques hydrosédimentaires et les conditions paléoclimatiques à l’échelle de la vallée de l’Arize. Les phénomènes observés à l’intérieur de la grotte ont été enregistré à l’extérieur de façon dégradée, mais des hypothèses de corrélations restent possibles entre les enregistrements dans la grotte et dans la vallée de l’Arize. La grotte du Mas d’Azil est donc un enregistreur très haute résolution des réponses hydrosédimentaires découlant des fluctuations climatiques, en particulier lors du dernier cycle glaciaire. Par les témoignages archéologiques insérés dans leur contexte géomorphologique, cette grotte souligne l’importance de la taphonomie différentielle des vestiges archéologiques et permet de les interpréter, de l’échelle du site jusqu’à celle des vallées du piémont nord-pyrénéen<br>The Mas d'Azil cave, crossed by the Arize river, has preserved evidence of the hydrosedimentary dynamics of the last glacial cycle, which conditioned both human occupation during the Upper Palaeolithic and the conservation of archaeological remains. Thus, how can the study of such a sedimentary recorder answer the question of the archaeological gaps of the last ice age?Hiatuses, either chronological or spatial, are observed in the cave's occupations. What significance can be attributed to them : absence of humans or differential conservation? At the transition MIS 3-MIS 2, a phase of sedimentary aggradation has constrained occupation in the cave, while playing a major role in the conservation or erosion of the remains. It allowed the partial conservation of the Aurignacian levels that it covers, but made the cave inaccessible for several millennia. Finally, the geomorphological study allows a very precise reflection on the organisation of space, access and movement of the populations inside the cave during the recent Middle Magdalenian.The cave also provides information on the hydrosedimentary dynamics and paleoclimatic conditions on the scale of the Arize valley. The phenomena observed inside the cave have been recorded outside in a degraded way, but correlation hypotheses remain possible between the recordings in the cave and in the Arize valley. The Mas d'Azil cave is therefore a very high-resolution recorder of hydrosedimentary responses resulting from climatic fluctuations, particularly during the last glacial cycle. Through the archaeological evidence inserted in its geomorphological context, this cave underlines the importance of the differential taphonomy of the archaeological remains and makes it possible to interpret them, from the scale of the site to that of the valleys of the northern Pyrenean foothills
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Sandström, Sonja. "Central Asian ice-marginal moraines of the global last glacial maximum : An analysis of topographic features affecting the glaciation pattern in the Tian Shan and Altai mountains." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-155171.
Повний текст джерелаАнотація:
Glacial runoff from the Tian Shan and Altai Mountains is an important water resource, especially for people living in the arid areas of Central Asia. Measured water volumes from glaciers have decreased, and glacier area have shrunk with 50-90% since the Little Ice Age. Lack of knowledge regarding glaciers in high mountain areas, and the impact from climate change makes this an important field to investigate. This thesis focuses on topographic features and their impact on spatial glaciation patterns; today and during the global last glacial maximum, 19-30 thousand years ago (ka). From selected marginal moraines in the Tian Shan and Altai mountains, with a deglaciation age between 19-30 ka, an analysis was created in ArcMap (GIS, Geographic Information System) with 1 arc second resolution ASTER GDEM2 (Digital Elevation Model) and in Google Earth. An elevation profile, hypsometry and mapping were created for the analysis. The interpretations made from the limited dataset resulted in topographic features affecting the glaciation extension today and percentage of decreasing glacier area since 19-30 ka, to be connected to north/south-facing direction of the drainage area and the elevation. Drainage areas experiencing the highest percentage of glacial shrinkage were southfacing and/or at elevation below 3961 m a.s.l.<br>Central Asia Paleoglaciology Project
Частини книг з теми "Last glaciation (MIS3 à 2)"
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Peterson, Jim A., S. Chandra, and Christian Lundberg. "Landforms from the Quaternary glaciation of Papua New Guinea: an overview of ice extent during the Last Glacial Maximum." In Developments in Quaternary Sciences. Elsevier, 2004. http://dx.doi.org/10.1016/s1571-0866(04)80136-2.
Повний текст джерела
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Robinson, Beren W., and Dolph Schluter. "Natural Selection and the Evolution of Adaptive Genetic Variation in Northern Freshwater Fishes." In Adaptive Genetic Variation In The Wild. Oxford University PressNew York, NY, 2000. http://dx.doi.org/10.1093/oso/9780195121834.003.0003.
Повний текст джерелаАнотація:
Abstract The fishes inhabiting depauperate northern postglacial lakes and rivers have lately experienced high rates of divergence and species formation. The study of these fishes provides insight into how genetic variation in populations is molded by divergent environmentally based selection and how genetic variation and selection interact to cause rapid diversification. We summarize patterns of variation and divergence in the trophic traits of these fishes and show that (1) populations in depauperate environments often have elevated levels of niche-based phenotypic variation, which regularly takes the form of trophic or resource polymorphisms, and which appear to represent cases of character release; (2) much of this variation is genetically based and is the product of disruptive selection; (3) parallel patterns of diversification occur within and among populations; (4) in some instances this process has led to stable species coexistence despite gene flow and incipient to full-blown sympatric speciation; and (5) a reserve of genetic variation persists in most postglacial fishes that may allow a response to certain kinds of environmental change. Contemporary patterns of variation reflect a recent history of natural selection that has operated since the last glaciation some 15,000 years ago, but they may also reflect species-level selection that has occurred over the much longer time scale of millions of years representing many glacial periods.
Тези доповідей конференцій з теми "Last glaciation (MIS3 à 2)"
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Solhjell, E., D. Moellenbeck, S. Yang, and J. W. Lakeman. "Geotechnical Properties of Subglacial Till at Baltic Sea Offshore Wind Farm Sites." In Offshore Technology Conference. OTC, 2024. http://dx.doi.org/10.4043/35172-ms.
Повний текст джерелаАнотація:
Abstract Detailed geotechnical soil investigation surveys have been performed with onshore laboratory testing and interpretation to support the development of two wind farm sites, herein denoted Sites 1 and 2, in the Baltic Sea, offshore Poland. The two wind farms are planned to have about 50 wind turbines each with a total combined capacity of about 1.4 GW. Large diameter monopiles have been selected as the foundation concept with a target embedment length ranging from 25 m to 40 m. The presence of an overconsolidated, high to ultra-high strength subglacial till layer, located at a depth of about 20 m to 40 m below seabed, is critical for the monopile foundation design. This layer presents significant challenges in terms of pile drivability, while also providing support to the monopile foundation design, both for the foundation capacity as well as the overall structural stability and integrity. The onshore laboratory testing included classification testing, static and cyclic strength testing, and testing to determine in-situ stress history and deformation properties. The interpretation included the integration of the geophysical data, geological, in-situ testing, and geotechnical laboratory testing to derive representative soil parameters for the subglacial till. X-ray scans showed signs of a complex geological process having taken place. The subglacial till is heterogeneous, with sandy, gravelly clay alternating with homogenized deformed clay layers. It exhibits poor sorting, including intermittent sand layers and erosive contacts at various depths. Seismic reflections display varying amplitudes and facies characteristics, reflecting its intricate geological history linked to the last glaciation event. The presence of inclined layers, deformed laminations, and fractures help to confirm glaciotectonic origins. Key parameters for strength assessment are presented. The cyclic strength properties are compared to experience from literature offering insights into its cyclic loading behavior. The thorough investigation provides essential insights into the geotechnical properties of subglacial till at the two offshore wind farm sites, crucial for designing reliable monopile foundations in challenging marine environments.