Journal articles: 'Glaciations du Quaternaire'

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Delmas, Magali, Marc Calvet, Yanni Gunnell, Régis Braucher, and Didier Bourlès. "Les glaciations quaternaires dans les Pyrénées ariégeoises : approche historiographique, données paléogéographiques et chronologiques nouvelles." Quaternaire, no. 23/1 (March 1, 2012): 61–85. http://dx.doi.org/10.4000/quaternaire.6091.

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Lebuis, J., and P. P. David. "La stratigraphie et les événements du Quaternaire de la partie occidentale de la Gaspésie, Québec." Dynamique et paléogéographie de l’inlandsis laurentidien 31, no. 3-4 (January 17, 2011): 275–96. http://dx.doi.org/10.7202/1000278ar.

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Une cartographie des dépôts meubles de la Gaspésie a permis d’identifier des unités lithostratigraphiques dont les noms formels sont proposés. Il existe des preuves pour deux glaciations distinctes représentées par des tills séparés par des intervalles de sédiments glacio-lacustres. La dernière glaciation a subi une inversion du sens de l’écoulement glaciaire et a permis la mise en place d’un troisième till, auquel est associé un diamicton glacio-marin déposé lors du vêlage des glaciers dans l’estuaire du Saint-Laurent. Enfin un quatrième till est dû à l’activité de calottes glaciaires confinées aux hautes terres du centre de la Gaspésie et qui ont donné naissance à des glaciers de vallée. Ces tills, en commençant par les plus vieux, ont été nommés Tamagodi, Langis, Petite-Matane et Grand-Volume. Les sédiments glacio-lacustres sous-jacents à chacun des deux premiers tills ne contiennent pas ou très peu de matière organique et n’ont pas été datés.

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Hétu, Bernard, and James T. Gray. "Le modelé glaciaire du centre de la Gaspésie septentrionale, Québec." Géographie physique et Quaternaire 39, no. 1 (November 29, 2007): 47–66. http://dx.doi.org/10.7202/032584ar.

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RÉSUMÉLe relief du centre de la Gaspésie septentrionale a grandement été modifié au cours des événements glaciaires du Quaternaire, mais l'érosion glaciaire s'est montrée très sélective. Les éléments du paysage les plus touchés sont les vallées et, dans une moindre mesure, les escarpements séparant les plateaux. Les vallées ont été surcreusées dans leur partie aval, parfois même sous le niveau de la mer. De plus, elles ont été calibrées et élargies, ce qui s'est traduit par l'apparition de parois abruptes, d'éperons tronqués et de vallées affluentes suspendues. Par ailleurs, la majorité des vallées principales ont vu leur tête défoncée et remplacée par un col glaciaire. En ce qui concerne les escarpements aux rebords des plateaux, la retouche glaciaire est très localisée, mais considérable puisqu'elle s'est traduite par l'apparition de cirques glaciaires. Les plateaux ne portent des traces de retouche glaciaire qu'aux endroits où la glace a pu être canalisée — à la tête des cirques défoncées et des vallées qui entaillent leurs rebords. On y trouve des champs de roches moutonnées, une topographie de knock-and-lochan et des lacs de surcreusement. Le modelé glaciaire du nord de la Gaspésie renvoit à deux types de glaciation différents: des glaciations de type alpin et des glaciation de type continental. L'âge exact des formes d'érosion glaciaire n'a pu être précisé, faute de dépôts corrélatifs, mais quelques observations suggèrent qu'elles sont le produit d'une longue suite de retouches étalées sur tout le Quaternaire, le dernier stade glaiciaire du Wisconsicien n'étant responsable que de légères retouches.

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Stauch, Georg, and Frank Lehmkuhl. "Quaternary glaciations in the Verkhoyansk Mountains, Northeast Siberia." Quaternary Research 74, no. 1 (July 2010): 145–55. http://dx.doi.org/10.1016/j.yqres.2010.04.003.

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AbstractGeomorphological mapping revealed five terminal moraines in the central Verkhoyansk Mountains. The youngest terminal moraine (I) was formed at least 50 ka ago according to new IRSL (infrared optically stimulated luminescence) dates. Older terminal moraines in the western foreland of the mountains are much more extensive in size. Although the smallest of these older moraines, moraine II, has not been dated, moraine III is 80 to 90 ka, moraine IV is 100 to 120 ka, and the outermost moraine V was deposited around 135 ka. This glaciation history is comparable to that of the Barents and Kara ice sheet and partly to that of the Polar Ural Mountains regarding the timing of the glaciations. However, no glaciation occurred during the global last glacial maximum (MIS 2). Based on cirque orientation and different glacier extent on the eastern and western flanks of the Verkhoyansk Mountains, local glaciations are mainly controlled by moisture transport from the west across the Eurasian continent. Thus glaciations in the Verkhoyansk Mountains not only express local climate changes but also are strongly influenced by the extent of the Eurasian ice sheets.

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Fulton, R. J., E. Irving, and P. M. Wheadon. "Stratigraphy and paleomagnetism of Brunhes and Matuyama (>790 ka) Quaternary deposits at Merritt, British Columbia." Canadian Journal of Earth Sciences 29, no. 1 (January 1, 1992): 76–92. http://dx.doi.org/10.1139/e92-009.

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A succession of Quaternary deposits in the Merritt basin of south-central British Columbia contains evidence for four glaciations and two interglaciations. Paleomagnetic signatures in these sediments are of three types: normal polarity, proposed to have been acquired during the Brunhes Normal Polarity Chron; reversed polarity, proposed to have been acquired during the Matuyama Reversed Polarity Chron; and reversed polarity (Matuyama age) all but obscured by a normally magnetized overprint (Brunhes age).Reversely magnetized deposits at the base of the succession include glacial lacustrine deposits, interpreted as representing two different glaciations, and a paleosol and a succession of nonglacial sediments, which are evidence of two interglaciations. As the reversed polarity of these deposits is proposed to have been acquired during the Matuyama Reversed Polarity Chron, they are older than 790 ka.Normally magnetized deposits, which make up the rest of the succession, contain evidence for only two glaciations, but traces of other glaciations may have been removed during the erosion interval encompassed by a major unconformity that underlies deposits of the last glaciation. All are referred to the Brunhes Normal Polarity Zone. In addition to these glacial and interglacial deposits, a series of normally magnetized Quaternary basalt flows forms a bench 90 m above the floor of the basin. These basalts were extruded after 790 ka but before the penultimate glaciation.

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Ramadhin, Christine, and Chuixiang Yi. "ESD Ideas: Why are glaciations slower than deglaciations?" Earth System Dynamics 11, no. 1 (January 17, 2020): 13–16. http://dx.doi.org/10.5194/esd-11-13-2020.

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Abstract. The Earth's climate during the Quaternary is dominated by short warm interglacials and longer cold glaciations paced by external forcings such as changes in insolation. Although not observed in the solar radiation changes, the time series of the cycles display asymmetry since transitions to full glacial conditions are slower than the termination of glaciations. Here an idea is proposed for the slower transition by identifying and describing two negative sea ice feedbacks dominant during the glaciation process that could serve as a control on the intermediate stage and decrease the pace of the process.

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Dortch, Jason M., Lewis A. Owen, and Marc W. Caffee. "Quaternary glaciation in the Nubra and Shyok valley confluence, northernmost Ladakh, India." Quaternary Research 74, no. 1 (July 2010): 132–44. http://dx.doi.org/10.1016/j.yqres.2010.04.013.

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AbstractThree glacial stages (Deshkit 1, Deshkit 2 and Dishkit 3 glacial stages) are identified in the Nubra and Shyok valleys in northernmost Ladakh, northwest India, on the basis of geomorphic field mapping, remote sensing, and 10Be terrestrial cosmogenic nuclide surface exposure dating. The glacial stages date to ∼ 45 ka (Deshkit 1 glacial stage), ∼ 81 ka (Deshkit 2 glacial stage) and ∼ 144 ka (Deshkit 3 glacial stage). A mean equilibrium line altitude depression of ∼ 290 m for the Deshkit 1 glacial stage was calculated using the area accumulation ratio, toe-to-headwall ratio, area–altitude, and area–altitude balance ratio methods. Comparison of glaciation in the Nubra and Shyok valleys with glaciations in the adjacent Central Karakoram of northern Pakistan and northern side of the Ladakh Range of northern India indicates that glaciation was synchronous on Milankovitch timescales across the region during MIS-6, but differed greatly in extent, with more extensive glaciation in the Karakoram than the morphostratigraphically equivalent glaciation on the northern slopes of the Ladakh Range. This highlights the strong contrast in the extent of glaciation across ranges in the Himalaya–Tibetan orogen, necessitating caution when correlating glacial successions within and between mountain ranges.

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Barendregt, R. W., J. S. Vincent, E. Irving, and J. Baker. "Magnetostratigraphy of Quaternary and late Tertiary sediments on Banks Island, Canadian Arctic Archipelago." Canadian Journal of Earth Sciences 35, no. 2 (February 1, 1998): 147–61. http://dx.doi.org/10.1139/e97-094.

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Sediments approximately 50 m thick from Banks Island (Canadian Arctic Archipelago) contain one of the longest terrestrial records of Pleistocene climate changes in North America. Samples have been obtained from 126 horizons distributed among four localitites, of which 116 horizons yielded acceptable paleomagnetic data. In sediments of the Matuyama Reversed Zone, there are recorded at least two and possibly as many as five full continental glaciations, two interglacial intervals, and a nonglacial interval at the beginning which is considered preglacial. Subzones attributable to the Olduvai and Jaramillo are present within the Matuyama Reversed Zone. The Brunhes Normal Zone records three full continental glaciations and three interglaciations. The Brunhes-Matuyama boundary occurs within interglacial deposits. The preglacial Worth Point Formation records a climate milder than today, and cooler than that of the late Tertiary. Based on floral, faunal, stratigraphic, and paleomagnetic constraints, a normal polarity sequence in the Worth Point Formation is assigned to the Olduvai normal polarity subzone (1.95-1.77 Ma). The earliest direct evidence of glaciation on Banks Island occurs in sediments that postdate the Worth Point Formation ( <<1.77 Ma). Consequently, in the western Canadian Arctic, the first continental glaciation postdated the first glaciation in the Canadian Cordillera (2.6 Ma) by at least a million years. The overall mean direction of the Quaternary geomagnetic field in Banks Island does not differ significantly from the geocentric axial dipole field, and these sediments contain no inclination error.

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Locke, William W. "The late Quaternary geomorphic and paleoclimatic history of the Cape Dyer area, easternmost Baffin Island, N.W.T." Canadian Journal of Earth Sciences 24, no. 6 (June 1, 1987): 1185–98. http://dx.doi.org/10.1139/e87-114.

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The Cape Dyer area of easternmost Baffin Island was isolated from the Laurentide Ice Sheet by the fiords of Cumberland Peninsula. Accordingly, the glacial chronology at Cape Dyer is that of local ice only and is indicative of the local climate throughout the late Quaternary. Six drift units, representing three periods of restricted glaciation and three of expanded glaciation, are present. Beyond the most distal drift is an area that has not been modified by glaciation.The expanded glaciations were dated through correlation on the bases of moraine morphology, soil development, and amino-acid racemization in marine mollusc shells incorporated in the drifts. No maximum age can be assigned to the earliest glaciation in the Cape Dyer area, but the last major glacial advance occurred about 70 000 years BP. The presence of extensive glaciofluvial features, faunal indicators of warm ocean water, and rapid soil development indicate that major glaciations of the Cape Dyer area accompanied winters warmer than at present but summers sufficiently cool to allow ice advance.The restricted ice advances were dated through correlation on the bases of moraine morphology, soil development, and lichen cover to the period between 9000 years BP and the present. They indicate ice extent similar to or less than at present throughout the past 60 000 years, in response to climatic conditions that were colder and dryer than the present until 9000 years BP, then slightly warmer than the present.Correlation with indicators of hemispheric and global climate indicates both in-phase and out-of-phase relationships. Glaciations at Cape Dyer are in phase with periods of high accumulation on Arctic ice caps, ice rafting of sediment in the Labrador Sea, and computed summer-insolation minima – winter-insolation maxima at 65°N latitude. This is as would be expected given the climatic interpretations of the drifts. Glaciation of the Cape Dyer area is out of phase with global ice volume as indicated by oxygen isotopes, suggesting the Antarctic dry valleys as a modem climatic analog for the Pleistocene eastern Canadian Arctic. The record of ice extent, climatic interpretations, and proposed model for climatic change are in agreement with most previously published reconstructions.

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DOTSENKO, Valeriy, and Ibragim KERIMOV. "ABOUT THE REASONS OF CLIMATE WARMING BASED ON STUDYING THE HISTORY OF QUATERNARY GLACIOSES OF THE CAUCASUS (ON THE EXAMPLE OF THE INTERDURCHIE TEREK AND THE ANDIAN KOISU)." Sustainable Development of Mountain Territories 12, no. 3 (September 30, 2020): 461–71. http://dx.doi.org/10.21177/1998-4502-2020-12-3-461-471.

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The Greater Caucasus experienced repeated glaciation during the Quaternary (early, middle, upper Pleistocene, late Glacial, and late Holocene), which occurred under changing climatic conditions and differentiated tectonic movements. These glaciations, of course, are associated with changes in terrain, the formation of new deposits, transgressions and regressions of the Caspian Sea, changes in vegetation and soil types, so the problem of glaciation affects all earth Sciences to varying degrees. The study of Quaternary glaciation, especially Holocene glaciation, is currently relevant for understanding climate change. Against the background of significant climate fluctuations within the epochs of glaciation, there are smaller cooling phases that cause the temporary onset of glaciers. Short-term climate fluctuations are manifested in oscillations – minor fluctuations in the languages of glaciers. All this indicates that the climate undergoes significant changes in a short time, which are reflected in the morphosculpture of the terrain, the latest deposits and modern precipitation. Glaciation of the Greater Caucasus in the Prikazbeksky region reached its maximum in the middle Pleistocene,when glaciers went far into the Ossetian basin. All these traces have been preserved due to the lower capacity of the Chanty-Argun glacier and its fluvioglacial flow, which developed during the late Pleistocene epoch. Volcanic activity, especially active in the late Pliocene and continuing up to the present time, is associated with the late horn stage of development of the Caucasus. The formation of the Rukhs-Dzuar molass formation more than 2 km thick in the late Pleistocene in the Ossetian basin of the Tersky-Caspian flexure is associated with the activity of volcanoes in the Kazbek volcanic region. In the early Pleistocene, volcanic activity on the BC decreased significantly. The most intense outbreak of volcanism in the Kazbek and Elbrus volcanic regions occurred at the beginning of the late Pleistocene, which roughly coincided with the maximum phase of the late Pleistocene (Bezengian) glaciation. Then, in the second half of the late Pleistocene, volcanic activity was manifested on the mount Kazbek. The last outbreak of volcanic activity occurred in the Holocene no more than 2-3 thousand years ago. Fresh lavas are available on Elbrus, Kazbek, in the Terek valley near villages. Sioni and on the Kel volcanic plateau. Fumarolic activity still continues on Elbrus. Thus, in the Kazbek region, eruptions occurred from the late Pliocene to the late Holocene inclusive. Keywords: Pleistocene, Holocene, glaciation stages, nival-glacial processes, causes of glaciations, climate change, anthropogenic factors, natural factors, Earth degassing, magmatogenic degassing branch, seismotectonic degassing branch, greenhouse gases, newest geodynamics, volcanism, mud regimes, volcanism, methane hydrates, land degradation, water reclamation.

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Tidey, Emily J., and Christina L. Hulbe. "Bathymetry and glacial geomorphology in the sub-Antarctic Auckland Islands." Antarctic Science 30, no. 6 (October 22, 2018): 357–70. http://dx.doi.org/10.1017/s0954102018000342.

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AbstractNew high-resolution multibeam swath bathymetry along the east coast of the Auckland Islands is combined with subaerial topography and evaluated in the context of Quaternary glaciation of the islands. The marine geomorphology represents a mixture of past and current processes so that submerged glacial features are more evident in some areas than others. Fjords in the central and southern parts of the coastline are characterized by well-preserved terminal moraines and other glacial features while fjords to the north tend to have more subdued glacial features and a smoother seabed. This is the farthest north record yet established of extensive sub-Antarctic glaciation, relative to the position of the modern sub-Antarctic and Polar Front. This is the first analysis of detailed sea floor geomorphology in the area and provides a starting point for new studies of paleoclimate and past glaciations.

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Petley, D. J. "Report on Session 2b." Geological Society, London, Engineering Geology Special Publications 7, no. 1 (1991): 409–14. http://dx.doi.org/10.1144/gsl.eng.1991.007.01.37.

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IntroductionNo part of geological time has had a more profound influence on the engineering characteristics of soils and rocks than the Quaternary period. Large areas of the earth’s surface are covered by superficial deposits of Quaternary age, and almost all surface soils and rocks affected by the changeds in climate which occurred in the Quaternary retain characteristics which have implications for engineering works at the present time.During the Quaternary period, at least five major glaciations occurred. During each glaciation, as the climate became colder, ice sheets spread from the poles and mountainous areas, to be followed by a retreat as warmer weather conditions prevailed during the inter-glacial periods. At the present time, in the Northern hemisphere, ice sheets cover approximately 10% of the total land area, but during the time of maximum glaciation in the Pleistocene, over 30% of the total land area was covered by ice.The volume of water taken up by the ice sheets caused significant variation in sea-levels. It has been estimated that the maximum and minimum sea-levels during the Quaternary were +200 m and -150 m 0D respectively. Indeed, following the main postglacial transgression at the end of the Devensian, the sea has been within 3 m of its present level for only the last 4000 or 5000 years. These large variation in sea-level significantly influenced the development and stability of slopes in coastal areas and inland.

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Burbank, Douglas W., and Kang Jian Cheng. "Relative dating of Quaternary moraines, Rongbuk valley, Mount Everest, Tibet: Implications for an ice sheet on the Tibetan Plateau." Quaternary Research 36, no. 1 (July 1991): 1–18. http://dx.doi.org/10.1016/0033-5894(91)90013-u.

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AbstractRelative-dating studies applied to high-altitude moraines (5000–5500 m) in the Rongbuk valley on the northern flank of Mt. Everest reveal strong contrasts in the weathering characteristics of the boulders exposed along moraine crests. These differences serve to define three intervals of major Pleistocene glaciation that, on the basis of the degree of weathering, are interpreted to extend back to at least the penultimate glaciation and probably encompass at least one still older glaciation. Either interpretation indicates that some of these moraines are considerably older than their previously assigned ages. The magnitude of equilibrium-line lowering during Neoglacial and late Pleistocene times is calculated to be ca. 50–100 and 350–450 m, respectively. The data described here are incompatible with the recently proposed model (Kuhle, 1987) for large-scale ice-sheet development on the Tibetan Plateau. The reconstructed equilibrium-line lowering in the Everest region is only 30% of that cited in the ice-sheet model. Moreover, the flow patterns and geometry of the former Rongbuk glaciers are in opposition to those proposed by the model. Based on the data from the Everest region, it appears that valley glaciation, rather than ice-sheet growth, characterized the southern margin of the Tibetan Plateau during the middle and late Pleistocene glaciations.

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May, Jan-Hendrik, Jana Zech, Roland Zech, Frank Preusser, Jaime Argollo, Peter W. Kubik, and Heinz Veit. "Reconstruction of a complex late Quaternary glacial landscape in the Cordillera de Cochabamba (Bolivia) based on a morphostratigraphic and multiple dating approach." Quaternary Research 76, no. 1 (July 2011): 106–18. http://dx.doi.org/10.1016/j.yqres.2011.05.003.

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AbstractAlthough glacial landscapes have previously been used for the reconstruction of late Quaternary glaciations in the Central Andes, only few data exist for the Eastern Cordillera in Bolivia. Here, we present results from detailed morphostratigraphic mapping and new data of surface exposure dating (SED), optically stimulated luminescence (OSL), and radiocarbon dating (14C) from the Huara Loma Valley, Cordillera de Cochabamba (Bolivia). Discrepancies between individual dating methods could be addressed within the context of a solid geomorphic framework. We identified two major glaciations. The older is not well constrained by the available data, whereas the younger glaciation is subdivided into at least four major glacial stages. Regarding the latter, a first advance dated to ~ 29–25 ka occurred roughly contemporaneous with the onset of the global last glacial maximum (LGM) and was followed by a less extensive (re-)advance around 20–18 ka. The local last glacial maximum (LLGM) in the Huara Loma Valley took place during the humid lateglacial ~17–16 ka, followed by several smaller readvances until ~10–11 ka, and complete deglaciation at the end of the Early Holocene.

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CONCHON, O. "Quaternary glaciations in Corsica." Quaternary Science Reviews 5 (1986): 429–32. http://dx.doi.org/10.1016/s0277-3791(86)80036-1.

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Rosqvist, Gunhild. "Quaternary glaciations in Africa." Quaternary Science Reviews 9, no. 2-3 (January 1990): 281–97. http://dx.doi.org/10.1016/0277-3791(90)90023-4.

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Andriashek, Laurence D., and René W. Barendregt. "Evidence for Early Pleistocene glaciation from borecore stratigraphy in north-central Alberta, Canada." Canadian Journal of Earth Sciences 54, no. 4 (April 2017): 445–60. http://dx.doi.org/10.1139/cjes-2016-0175.

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Pleistocene sediments collected in north-central Alberta, Canada, were subsampled and studied for paleomagnetic remanence characteristics. A magnetostratigraphy has been established for sediments previously assumed to represent multiple continental (Laurentide) glaciations but for which no geochronology was available. Based on the Quaternary record elsewhere in Alberta and Saskatchewan, it was thought that some of these sediments were deposited during pre-late Wisconsinan glaciations. The Quaternary sedimentary successions of north-central Alberta have a thickness up to 300 m within buried valleys and are composed of diamicts interbedded with glaciolacustrine and outwash sediments. Most of the sampled units are not accessible from outcrop, and their sedimentology and stratigraphy is derived from core data only. In 4 of 16 borecores sampled to date, diamict that correlates with the Bronson Lake Formation till is reversely magnetized, indicating an Early Pleistocene age. This formation is underlain by either Empress Formation sediments or Colorado Group shale, and is overlain by one or more normally magnetized glacigenic sedimentary units of the Bonnyville, Marie Creek, and Grand Centre formations, respectively. This new record of Early Pleistocene glaciation in north-central Alberta places the westernmost extent of earliest Laurentide ice at least 300 km farther west than its previously established limit in the Saskatoon and Regina regions of the Canadian Interior Plains, but still to the east of the maximum extent of the Late Wisconsinan (Late Pleistocene) Laurentide Ice Sheet, which extended into the foothills of the Alberta and Montana Rocky Mountains.

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Clague, John J. "The Quaternary stratigraphic record of British Columbia—evidence for episodic sedimentation and erosion controlled by glaciation." Canadian Journal of Earth Sciences 23, no. 6 (June 1, 1986): 885–94. http://dx.doi.org/10.1139/e86-090.

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The terrestrial Quaternary stratigraphic record of British Columbia is largely a product of brief depositional events separated by long periods of nondeposition and erosion. Thick, stratified Quaternary sediments are present mainly in valleys and coastal lowlands and accumulated during periods of growth and decay of the Cordilleran Ice Sheet. At glacial maxima, till was deposited over large areas of low and moderate relief. However, at the same time, much of the landscape was eroded by glaciers.Sedimentation has been more restricted and has occurred at lower rates during nonglacial periods than during glaciations. On land, the only important sediment accumulation sites during nonglacials have been lakes, floodplains, and fans. However, large amounts of sediment have accumulated offshore, especially in fjords and basins such as the Strait of Georgia. Because of the restricted aspect of sedimentation during nonglacials, the stratigraphic record of these periods is meagre. In most places, true nonglacial units are thin and discontinuous, or they are absent altogether. Commonly, a nonglacial period is recorded only by an unconformity produced when streams incised valley fills shortly after the end of the preceding glaciation.

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Böse, Margot. "Quaternary glaciations of northern Europe." Quaternary International 279-280 (November 2012): 61. http://dx.doi.org/10.1016/j.quaint.2012.07.268.

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Sarikaya, Mehmet Akif. "Late Quaternary glaciations in Turkey." Quaternary International 279-280 (November 2012): 427. http://dx.doi.org/10.1016/j.quaint.2012.08.1384.

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Böse, Margot, Christopher Lüthgens, Jonathan R. Lee, and James Rose. "Quaternary glaciations of northern Europe." Quaternary Science Reviews 44 (June 2012): 1–25. http://dx.doi.org/10.1016/j.quascirev.2012.04.017.

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Brown, Iain M. "Quaternary glaciations of New Guinea." Quaternary Science Reviews 9, no. 2-3 (January 1990): 273–80. http://dx.doi.org/10.1016/0277-3791(90)90022-3.

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van Vliet-Lanoë, Brigitte. "Le prélude au Quaternaire : les modalités d'entrée en glaciation (65 Ma - 2,2 Ma)." Quaternaire, no. 18/2 (June 1, 2007): 111–28. http://dx.doi.org/10.4000/quaternaire.1006.

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Zech, Wolfgang, Rupert Bäumler, Oksana Savoskul, Anatoli Ni, and Maxim Petrov. "Bodengeographische Beobachtungen zur pleistozänen und holozänen Vergletscherung des Westlichen Tienshan (Usbekistan)." E&G Quaternary Science Journal 46, no. 1 (January 1, 1996): 144–51. http://dx.doi.org/10.3285/eg.46.1.11.

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Abstract. Soil geographic studies were carried out in the Oigaing valley between Ugamsky and Pskemsky range NE of Tashkent (W-Tienshan, Republic of Uzbekistan) with special regard to the Pleistocene and Holocene glaciation. Clear end moraines of the last main glaciation are preserved at the junction of Maidan and Oigaing river at 1500-1600 m a.s.l. They show intensively weathered soils with a depth of more than 80 cm. Similar deposits ol presumably Pleistocene or late glacial origin are also located upvalley at the embouchure of numerous side valleys (Beschtor, Tekesch, Aütor) into the main valley of Oigaing. All side valleys are characterized by late glacial ground and end moraines in 2500-2700 m a.s.l. showing intensively weathered brown colored soils of 30-40 cm depth. Further moraines of Holocene or recent origin are located approach of the recent glaciers which descend to 3000-3200 m. They show shallow, initial soils, and presumably correspond with glacial advances during the so-called "Little Ice Age" with a maximum advance at about 1850 in the Alps, and in the middle Holocene at about 2000 or 4000 a BP. Highly weathered, and rubefied interglacial soils developed from old Quaternary gravel are preserved above high glacial ice marginal grounds of the last main glaciation (>2850 m a.s.l.) in the lower side valley of the Barkrak river. In the upper valley huge drift could be shown above the ice marginal grounds, but without typical forms of morainic deposits. They give evidence for older glaciations with a greater extent compared with the last main glaciation. However, no corresponding moraines are present in the working area.

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Wang, Xiaoli, Jiangyong Qu, Naifa Liu, Xinkang Bao, and Sen Song. "Limited gene flow and partial isolation phylogeography of Himalayan snowcock Tetraogallus himalayensis based on part mitochondrial D-loop sequences." Current Zoology 57, no. 6 (December 1, 2011): 758–67. http://dx.doi.org/10.1093/czoolo/57.6.758.

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Abstract Himalayan snowcock Tetraogallus himalayensis are distributed in alpine and subalpine areas in China. We used mitochondrial DNA control-region data to investigate the origin and past demographic change in sixty-seven Himalayan snowcock T. himalayensis. The fragments of 1155 nucleotides from the control region of mitochondrial DNA were sequenced, and 57 polymorphic positions defined 37 haplotypes. A high level of genetic diversity was detected in all populations sampled and may be associated isolation of the mountains and habitat fragmentation and deterioration from Quaternary glaciations. In the phylogenetic tree, all haplotypes grouped into four groups: clade A (Kunlun Mountains clade), clade B (Northern Qinghai-Tibetan Plateau clade), clade C (Tianshan Mountains clade) and clade D (Kalakunlun Mountains clade). We found a low level of gene flow and significant genetic differentiation among all populations. Based on divergence time we suggest that the divergence of Himalayan snowcock occurred in the middle Pleistocene inter-glaciation, and expansion occurred in the glaciation. Analysis of mtDNA D-loop sequences confirmed demographic population expansion, as did our non-significant mismatch distribution analysis. In conclusion, limited gene flow and a pattern of partial isolation phylogeographic was found in geographic populations of T. himalayansis based on the analysis on mtDNA D-loop sequences.

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SHI, Y. "Quaternary glaciation in China." Quaternary Science Reviews 5 (1986): 503–7. http://dx.doi.org/10.1016/s0277-3791(86)80044-0.

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Rother, H., and J. Shulmeister. "Synoptic climate change as a driver of late Quaternary glaciations in the mid-latitudes of the Southern Hemisphere." Climate of the Past 2, no. 1 (May 12, 2006): 11–19. http://dx.doi.org/10.5194/cp-2-11-2006.

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Abstract. The relative timing of late Quaternary glacial advances in mid-latitude (40-55° S) mountain belts of the Southern Hemisphere (SH) has become a critical focus in the debate on global climate teleconnections. On the basis of glacial data from New Zealand (NZ) and southern South America it has been argued that interhemispheric synchrony or asynchrony of Quaternary glacial events is due to Northern Hemisphere (NH) forcing of SH climate through either the ocean or atmosphere systems. Here we present a glacial snow-mass balance model that demonstrates that large scale glaciation in the temperate and hyperhumid Southern Alps of New Zealand can be generated with moderate cooling. This is because the rapid conversion of precipitation from rainfall to snowfall drives massive ice accumulation at small thermal changes (1-4°C). Our model is consistent with recent paleo-environmental reconstructions showing that glacial advances in New Zealand during the Last Glacial Maximum (LGM) and the Last Glacial Interglacial Transition (LGIT) occurred under very moderate cooling. We suggest that such moderate cooling could be generated by changes in synoptic climatology, specifically through enhanced regional flow of moist westerly air masses. Our results imply that NH climate forcing may not have been the exclusive driver of Quaternary glaciations in New Zealand and that synoptic style climate variations are a better explanation for at least some late Quaternary glacial events, in particular during the LGIT (e.g. Younger Dryas and/or Antarctic Cold Reversal).

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Scapozza, Cristian. "Evidence of paraglacial and paraperiglacial crisis in Alpine sediment transfer since the last glaciation (Ticino, Switzerland)." Quaternaire, no. 27/2 (June 1, 2016): 139–55. http://dx.doi.org/10.4000/quaternaire.7805.

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Paillard, Didier. "Quaternary glaciations: from observations to theories." Quaternary Science Reviews 107 (January 2015): 11–24. http://dx.doi.org/10.1016/j.quascirev.2014.10.002.

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Paillard, D. "On Quaternary glaciations, observations and theories." Quaternary Science Reviews 120 (July 2015): 128–32. http://dx.doi.org/10.1016/j.quascirev.2015.05.017.

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Stauch, G., and L. Gualtieri. "Late Quaternary glaciations in northeastern Russia." Journal of Quaternary Science 23, no. 6-7 (September 2008): 545–58. http://dx.doi.org/10.1002/jqs.1211.

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Ingólfsson, Ó. "Fingerprints of Quaternary glaciations on Svalbard." Geological Society, London, Special Publications 354, no. 1 (2011): 15–31. http://dx.doi.org/10.1144/sp354.2.

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Ghil, M., A. Mullhaupt, and P. Pestiaux. "Deep water formation and Quaternary glaciations." Climate Dynamics 2, no. 1 (May 1987): 1–10. http://dx.doi.org/10.1007/bf01088850.

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Rabassa, Jorge, and Chalmers M. Clapperton. "Quaternary glaciations of the southern Andes." Quaternary Science Reviews 9, no. 2-3 (January 1990): 153–74. http://dx.doi.org/10.1016/0277-3791(90)90016-4.

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Jansson, Peter, Cecilia Richardson, and Stig Jonsson. "Assessment of requirements for cirque formation in northern Sweden." Annals of Glaciology 28 (1999): 16–22. http://dx.doi.org/10.3189/172756499781821959.

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AbstractCirques in the Rassepautasjtjåkka massif currently lack glaciers and the geomorphology indicates that no glaciers occupied the cirques during the Holocene. The current climatic conditions in the cirques can be assessed using available climatic data; air temperature at Rassepautasjtjåkka, summer and winter balances of adjacent glaciers, and general precipitation patterns in northern Sweden. The data suggest that either a significant change in precipitation and wind regime or a moderate change in temperature is required to initiate a cirque glacier in the massif. Formation of a wet-based erosive glacier requires warmer winters with higher accumulation rates, equivalent to a more maritime influence in the area. Studies of current atmospheric circulation suggest that strong west- east circulation, associated with a northerly position of the polar front, is favourable for increased accumulation. Using typical erosion rates from present glaciers, we see that ~ 10% of the last 3 Myr may be required for forming the Rassepautasjtjåkka cirques. This is a significant portion of time since most of the glacial cycles are spent in states of interglacials, maximum glaciation or mountain-based glaciation. Marine sediments from the Norwegian Sea provide indications of minor glaciations back to ~12.6 Myr and, hence, cirque-formation periods are not restricted to Quaternary. Thus, it is possible that many cirque forms have a much longer history than previously recognized.

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Jeppsson, Lennart, and Mikael Calner. "The Silurian Mulde Event and a scenario for secundo–secundo events." Transactions of the Royal Society of Edinburgh: Earth Sciences 93, no. 2 (June 2002): 135–54. http://dx.doi.org/10.1017/s0263593300000377.

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ABSTRACTGraphic correlation using graptolites and conodonts provides a high-resolution timescale for correlating from coastal to deep oceanic sections and, thereby, also a detailed record of the sequence of changes during the Mulde Secundo-Secundo Event. That interval includes sedimentary facies otherwise unknown in older Wenlock to early Ludlow strata on Gotland. The identified sequence of changes includes a detailed record of, in order: two extinctions (Datum points 1 and 1·5); widespread deposition of carbon-rich sediments extensive enough to cause a δ13C increase of c. 4.8‰, the onset, maximum and end of a sea-level fall and rise of at least 16 m during 30 kyr; a third extinction (Datum 2); a disaster fauna; and a slow faunal recovery. Thus, a secondary result of the event was a weakened greenhouse effect triggering a glaciation: the Gannarve Glaciation (new term). The order of changes proves that regression did not cause the extinctions. Faunal and sea-level changes, as well as the sedimentary succession, fit well with predictions based on an oceanic model. Extinctions were primarily caused by a severe drop in primary planktonic productivity, causing starvation among planktonic larvae in non-coastal settings. The Grötlingbo Bentonite (new term), the thickest in the Wenlock of Gotland, was deposited across the basin shortly after Datum 2. Temporal resolution is high enough to permit some comparison with Quaternary glaciations.

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Sosa-Pivatto, María, Gonzalo A. Camps, Matías C. Baranzelli, Anahí Espíndola, Alicia N. Sérsic, and Andrea Cosacov. "Connection, isolation and reconnection: Quaternary climatic oscillations and the Andes shaped the phylogeographical patterns of the Patagonian bee Centris cineraria (Apidae)." Biological Journal of the Linnean Society 131, no. 2 (August 26, 2020): 396–416. http://dx.doi.org/10.1093/biolinnean/blaa116.

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Abstract The joint effect of the Andes as a geographical barrier and the Quaternary glaciations as promoters of genetic divergence remains virtually unexplored in southern South America. To help fill this knowledge gap, in this study we investigated the demographic history of Centris cineraria, a solitary bee mainly distributed in Patagonia. We used mitochondrial and nuclear markers and performed phylogeographical and dating analyses, adjusted spatio-temporal diffusion and species distribution models, and used Approximate Bayesian Computation to identify likely historical demographic scenarios. Our results revealed that during glacial periods the Andes represented a barrier due to the extent of the ice-sheets and the occurrence of unsuitable habitats, while interglacials allowed for gene flow across the Andes. Secondary contact between previously isolated lineages was evident across at least two low-altitude Andean areas, the northern one being a putative glacial refugium. Our findings also suggest that C. cineraria has persisted in situ in four periglacial refugia located along a north–south transect, congruent with the maximum extent of the ice sheet during the Greatest Patagonian Glaciation. As the first phylogeographical study of Patagonian insects, our work reveals that the interaction between Quaternary climatic oscillations and the Andes as a barrier was the main driver of the spatial and demographic history of C. cineraria.

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Barr, Iestyn D., and Chris D. Clark. "Late Quaternary glaciations in Far NE Russia; combining moraines, topography and chronology to assess regional and global glaciation synchrony." Quaternary Science Reviews 53 (October 2012): 72–87. http://dx.doi.org/10.1016/j.quascirev.2012.08.004.

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Owen, Lewis A., Ruth Robinson, Douglas I. Benn, Robert C. Finkel, Nicole K. Davis, Chaolu Yi, Jaakko Putkonen, Dewen Li, and Andrew S. Murray. "Quaternary glaciation of Mount Everest." Quaternary Science Reviews 28, no. 15-16 (July 2009): 1412–33. http://dx.doi.org/10.1016/j.quascirev.2009.02.010.

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Sizov, Oleg, Anna Volvakh, Anatoly Molodkov, Andrey Vishnevskiy, Andrey Soromotin, and Evgeny Abakumov. "Lithological and geomorphological indicators of glacial genesis in the upper Quaternary strata, Nadym River basin, Western Siberia." Solid Earth 11, no. 6 (November 10, 2020): 2047–74. http://dx.doi.org/10.5194/se-11-2047-2020.

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Abstract. Analysing the genesis of Quaternary sediments is important for understanding the glaciation history and development of marine sediments in the northern part of Western Siberia. The problem is relevant since there is no consistent concept of the Quaternary sediment genesis in the north of Western Siberia. The formation of sediments is associated with marine, glacial and interglacial sedimentation conditions. The research objective is to identify the persistent features characterising the conditions of sedimentation and relief formation using the Nadym River basin as an example. The best method for studying this problem is a comprehensive analysis of the lithological, chronostratigraphic, petrographic and geomorphological studies of the Quaternary sediment upper strata. This study provides data from the analysis of the basic characteristics of quartz grains at the site. The rounding and morphology of the quartz grains provide evidence of possible glacial processing of some of the site strata. A petrographic study of selected boulder samples was performed. Some of them, by the shape and presence of striation, can be attributed to ice basins. The first use of a detailed digital elevation model applied to the study area made it possible to identify specific relief forms that could very likely be created during glaciations. Based on the analysis, we propose to consider the vast lake alluvial plains in the Nadym River basin as periglacial regions. This idea lays the lithological framework for understanding the reasons for the formation of the modern landscape structure. The materials and descriptions provided are of interest to researchers of Quaternary sediments, topography, vegetation and soil cover, particularly researchers engaged in revising the history of the natural environment development in the north of Western Siberia.

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Ludwikowska-Kędzia, Małgorzata, Halina Pawelec, and Grzegorz Adamiec. "Sedimentological interpretation and stratigraphical position of glacigenic deposits in the Napęków area (Holy Cross Mountains, Poland)." Geologos 21, no. 4 (December 1, 2015): 261–84. http://dx.doi.org/10.1515/logos-2015-0018.

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AbstractThe identification of depositional conditions and stratigraphical position of glacigenic deposits in the Napęków area is important for the genetic and stratigraphical interpretation of Quaternary deposits in the central part of the Holy Cross Mountains, as well as for a revision of the course and extent of Middle Polish (Saalian) glaciations. These deposits comprise a series of diamictons which occur between sandy-gravelly deposits. Based on results of macro- and microscopic sedimentological investigations, analysis of heavy mineral composition, roundness and frosting of quartz grains, as well as OSL dating, this complex must have formed during the Odranian Glaciation (Drenthe, Saalian, MIS 6). Sandy-gravelly deposits are of fluvioglacial and melt-out origin. Diamictons represent subglacial traction till. Their facies diversity is a result of variations in time and space, complex processes of deposition and deformation, responsible for their formation at the base of the active ice sheet. This glacigenic depositional complex was transformed by erosion-denudation and aeolian processes in a periglacial environment during the Vistulian (Weichselian, MIS 5d-2).

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Dauvillier, A. "Note sur la liaison continentale Amérique du Sud-Antarctique." Cahiers de géographie du Québec 17, no. 41 (April 12, 2005): 339–42. http://dx.doi.org/10.7202/021122ar.

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Bobrowsky, Peter, and Nathaniel W. Rutter. "The Quaternary Geologic History of the Canadian Rocky Mountains." Géographie physique et Quaternaire 46, no. 1 (November 23, 2007): 5–50. http://dx.doi.org/10.7202/032887ar.

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ABSTRACT The Canadian Rocky Mountains figured prominently during the glacial history of western Canada. First as a western limit or boundary to the Laurentide Ice Sheet, second as an eastern margin of the Cordilleran Ice Sheet, and finally as a centre of local Montane ice. Throughout the Quaternary, complex interactions of glacier ice from these three ice sources markedly changed the physical form of the Rocky Mountains, Trench and Foothills areas. Investigations into the Quaternary history of this region have been ongoing since the beginning of the last century. Since about 1950, the number of studies performed in this area have increased significantly. This paper briefly reviews the historical accomplishments of Quaternary work in the region up to the period of about 1950. From this time to the present, individual study efforts are examined in detail according to the three geographic regions: 1) the northern Rocky Mountains (from the Liard Plateau south to the McGregor Plateau), 2) the central Rocky Mountains (from the McGregor Plateau south to the Porcupine Hills) and 3) the southern Rocky Mountains (from the Porcupine Hills south to the international border). In the northern region, geologic data suggest a maximum of two Rocky Mountain glaciations and only one Laurentide glaciation and no ice coalescence. In the central region, three of four Rocky Mountain events, and at least two Laurentide events are known. Only in the central region is there good evidence for ice coalescence, but the timing of this event is not clearly established. In the south, at least three Rocky Mountain episodes and a variable number of Laurentide episodes are recognized. There is no evidence for ice coalescence. A number of facts support the proposal that Cordilleran ice crossed the Continental Divide and joined with local Montane ice at several locations. However, this expansion of western ice occurred before the Late Wisconsinan in all areas but Jasper. In general, the chronological data presented suggest that the Late Wisconsinan glaciation in the Rocky Mountains was a short-lived event which started around or after 20 ka years ago and ended before 12 ka ago.

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Shanahan, Timothy M., and Marek Zreda. "Chronology of Quaternary glaciations in East Africa." Earth and Planetary Science Letters 177, no. 1-2 (April 15, 2000): 23–42. http://dx.doi.org/10.1016/s0012-821x(00)00029-7.

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Akcar, Naki. "Quaternary Glaciations at Uludag Mountain (NW Turkey)." Quaternary International 279-280 (November 2012): 13. http://dx.doi.org/10.1016/j.quaint.2012.07.051.

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46

Sarıkaya, Mehmet Akif, and Attila Çiner. "Late Quaternary glaciations in the eastern Mediterranean." Geological Society, London, Special Publications 433, no. 1 (December 11, 2015): 289–305. http://dx.doi.org/10.1144/sp433.4.

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MANN, DANIEL H., RONALD S. SLETTEN, and RICHARD E. REANIER. "Quaternary glaciations of the Rongbuk Valley, Tibet." Journal of Quaternary Science 11, no. 4 (July 1996): 267–80. http://dx.doi.org/10.1002/(sici)1099-1417(199607/08)11:4<267::aid-jqs242>3.0.co;2-v.

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48

Veyret, Y. "Quaternary glaciations in the French Massif Central." Quaternary Science Reviews 5 (January 1986): 395–96. http://dx.doi.org/10.1016/0277-3791(86)90202-7.

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Bednarski, Jan. "Late Quaternary glacial and sea-level events, Clements Markham Inlet, northern Ellesmere Island, Arctic Canada." Canadian Journal of Earth Sciences 23, no. 9 (September 1, 1986): 1343–55. http://dx.doi.org/10.1139/e86-129.

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Clements Markham Inlet cuts into the Grant Land Mountains of the northernmost coast of Ellesmere Island. The head of the inlet is bounded on three sides by mountain ice caps that surround lowlands mantled by extensive raised marine deposits. Fieldwork and mapping of late Quaternary sediments were used to determine the limits of past glaciations and the nature of ice retreat from the inlet head. Forty-five radiocarbon dates on driftwood and marine shells provide a deglacial chronology and document related sea-level adjustments.High-level ice-marginal meltwater channels and mountain summit erratics indicate that ice once inundated all of Clements Markham Inlet. During at least one of these undated glaciations, ice flowed unconstrained by the local topography. In contrast, the most recent glaciation involved confluent trunk glaciers, which terminated near the head of the inlet. Beyond this terminus, smaller glaciers entering the sides of the inlet debouched into a glacioisostatically depressed sea (full glacial sea). Retreat from the last glaciation is documented by moraines, kame terraces, and ice-contact deltas.Inside the ice limit at the head of the inlet, sections commonly show that a marine transgression occurred immediately after the retreat of the ice. Conversely, sections outside the last ice limit, along the sides of the inlet, show complex intercalations of marine and glacigenic sediments. These indicate proximal ice-front conditions where small valley glaciers locally contacted the sea.The oldest date on the last ice limit is 9845 BP. After this, slow retreat was in progress, and some glaciers were within 6 km of their current positions by ca. 9700 BP. At the head of the inlet, the mouths of the confluent valleys became ice free by 8000 BP. After 8000 BP, glacial retreat accelerated greatly, so that the entire lowland became ice free within 400 years.Relative sea-level curves from the inlet indicate ice-load changes that confirm this pattern of ice retreat. Outside the last ice limit, the full glacial sea reached 124 m asl by at least 10 000 BP. Emergence from this sea occurred slowly between at least 10 000 and 8000 BP (0.72 m 100 year−1). This period was followed by "normal" rapid postglacial emergence, which decelerated to the present.The marine limit of the full glacial sea rises from 92 m asl, at the outer coast, to 124 m asl near the last ice limit at the head of the inlet. Initial emergence from the full glacial sea occurred simultaneously throughout the inlet. On the proximal side of the last ice limit, the marine limit descends in the up-ice direction and becomes progressively younger. Individual strandlines tilt up in a southwesterly direction towards the central Grant Land Mountains, suggesting a former centre of glacio-isostatic loading in that area.

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Broster, Bruce E., and John J. Clague. "Advance and retreat glacigenic deformation at Williams Lake, British Columbia." Canadian Journal of Earth Sciences 24, no. 7 (July 1, 1987): 1421–30. http://dx.doi.org/10.1139/e87-134.

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Glacigenic deformation structures at Williams Lake, British Columbia, occur within stratified Quaternary sediments that both overlie and underlie lodgement till of the last (Fraser = Late Wisconsinan) glaciation. The main structures in sediments below the lodgement till are faults, joints, and clastic dikes produced by glacier overriding during Late Wisconsinan time. The orientation of these structures is closely related to the direction of glacier flow at Williams Lake. Their character and stratigraphic position suggest that the substrate in this area was partly frozen and partly unfrozen when covered by ice during the Fraser Glaciation.A different suite of glacigenic deformation structures is found in sediments above the lodgement till. These include complex folds, load casts, and high-angle faults formed during deglaciation as a result of loss of ice support and collapse. These structures yield information on the local pattern of ice decay, but bear no relationship to the regional direction of Late Wisconsinan glacier flow.

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Journal articles on the topic 'Glaciations du Quaternaire'

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