Journal articles: 'Glacial sedimentation'

1

Finkl, Charles W. "Glacial-Marine Sedimentation." Sedimentary Geology 45, no. 3-4 (November 1985): 315–16. http://dx.doi.org/10.1016/0037-0738(85)90008-9.

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Molnia, Bruce F., Austin Post, and Paul R. Carlson. "20th-century glacial-marine sedimentation in Vitus Lake, Bering Glacier, Alaska, U. S. A." Annals of Glaciology 22 (1996): 205–10. http://dx.doi.org/10.3189/1996aog22-1-205-210.

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Vitus Lake, the ice-marginal basin at the southeastern edge of Bering Glacier, Alaska, U.S.A., is a site of modern, rapid, glacial-marine sedimentation. Rather than being a fresh-water lake, Vitus Lake is a tidally influenced, marine to brackish embayment connected to the Pacifie Ocean by an inlet, the Seal River. Vitus Lake consists of five deep bedrock basins, separated by interbasinal highs. Glacial erosion has cut these basins as much as 250 m below sea level. High-resolution seismic reflection surveys conducted in 1991 and 1993 of four of Vitus Lake’s basins reveal a complex, variable three-component acoustic stratigraphy. Although not fully sampled, the stratigraphy is inferred to be primarily glacial-marine units of (1) basal contorted and deformed glacial-marine and glacial sediments deposited by basal ice-contact processes and submarine mass-wasting; (2) acoustically well-stratified glacial-marine sediment, which unconformably overlies the basal unit and which grades upward into (3) acoustically transparent or nearly transparent glacial-marine sediment. Maximum thicknesses of conformable glacial-marine sediment exceed 100 m. All of the acoustically transparent and stratified deposits in Vitus Lake are modern in age, having accumulated between 1967 and 1993. The basins where these three-part sequences of “present-day” glacial-marine sediment are accumulating are themselves cut into older sequences of stratified glacial and glacial-marine deposits. These older units outcrop on the islands in Vitus Lake.In 1967, as the result of a major surge, glacier ice completely filled all five basins. Subsequent terminus retreat, which continued through August 1993, exposed these basins, providing new locations for glacial-marine sediment accumulation. A correlation of sediment thicknesses measured from seismic profiles at specific locations within the basins, with the year that each location became ice-free, shows that the sediment accumulation at some locations exceeds 10 m year−1.

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3

Molnia, Bruce F., Austin Post, and Paul R. Carlson. "20th-century glacial-marine sedimentation in Vitus Lake, Bering Glacier, Alaska, U. S. A." Annals of Glaciology 22 (1996): 205–10. http://dx.doi.org/10.1017/s0260305500015433.

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Vitus Lake, the ice-marginal basin at the southeastern edge of Bering Glacier, Alaska, U.S.A., is a site of modern, rapid, glacial-marine sedimentation. Rather than being a fresh-water lake, Vitus Lake is a tidally influenced, marine to brackish embayment connected to the Pacifie Ocean by an inlet, the Seal River. Vitus Lake consists of five deep bedrock basins, separated by interbasinal highs. Glacial erosion has cut these basins as much as 250 m below sea level. High-resolution seismic reflection surveys conducted in 1991 and 1993 of four of Vitus Lake’s basins reveal a complex, variable three-component acoustic stratigraphy. Although not fully sampled, the stratigraphy is inferred to be primarily glacial-marine units of (1) basal contorted and deformed glacial-marine and glacial sediments deposited by basal ice-contact processes and submarine mass-wasting; (2) acoustically well-stratified glacial-marine sediment, which unconformably overlies the basal unit and which grades upward into (3) acoustically transparent or nearly transparent glacial-marine sediment. Maximum thicknesses of conformable glacial-marine sediment exceed 100 m. All of the acoustically transparent and stratified deposits in Vitus Lake are modern in age, having accumulated between 1967 and 1993. The basins where these three-part sequences of “present-day” glacial-marine sediment are accumulating are themselves cut into older sequences of stratified glacial and glacial-marine deposits. These older units outcrop on the islands in Vitus Lake.In 1967, as the result of a major surge, glacier ice completely filled all five basins. Subsequent terminus retreat, which continued through August 1993, exposed these basins, providing new locations for glacial-marine sediment accumulation. A correlation of sediment thicknesses measured from seismic profiles at specific locations within the basins, with the year that each location became ice-free, shows that the sediment accumulation at some locations exceeds 10 m year−1.

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4

Andrews, John T., John B. Anderson, and Gail M. Ashley. "Glacial Marine Sedimentation: Paleoclimatic Significance." Arctic and Alpine Research 24, no. 3 (August 1992): 263. http://dx.doi.org/10.2307/1551673.

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5

Pudsey, Carol J. "Glacial marine sedimentation; paleoclimatic significance." Marine and Petroleum Geology 10, no. 3 (June 1993): 295. http://dx.doi.org/10.1016/0264-8172(93)90111-5.

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6

Li, Qianyu, Fan Zheng, Muhong Chen, Rong Xiang, Peijun Qiao, Lei Shao, and Xinrong Cheng. "Glacial Paleoceanography off the Mouth of the Mekong River, Southern South China Sea, During the last 500 ka." Quaternary Research 73, no. 3 (May 2010): 563–72. http://dx.doi.org/10.1016/j.yqres.2010.03.003.

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We have analyzed core MD01-2392, ∽360 km east of the Mekong River mouth in the South China Sea (SCS). Over the past 500 ka, planktonic foraminiferal oxygen-isotopic values are consistently lighter than northern SCS and open-ocean records by up to 0.5‰, indicating the influence of run-off from the Mekong River during both glacial and interglacial periods. Carbonate content is higher during interglacials; sedimentation rates were higher during glacials. Increased sedimentation rates since 30 ka imply increased run-off during the last glacial maximum and Holocene Period. Contrary to general experience, in which it is classed as a warm species for temperature estimates, the thermocline-dwelling species Pulleniatina obliquiloculata increased its numbers during glacial periods. This implies an estuarine circulation and even brackish-water caps during glacial periods, reinforcing the sense of strong run-off. In an overall decline of warm water, the thermocline shoaled stepwise, with rapid rises across the glacial terminations. We infer that the southern SCS was opened to an influx of Indian Ocean waters through southern passages at those times of rising sea levels.

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Alam, M., and D. J. W. Piper. "Pre-Wisconsin stratigraphy and paleoclimates off Atlantic Canada, and its bearing on glaciation in Québec." Cadre stratigraphique et paléoclimatique 31, no. 1-2 (December 9, 2010): 15–22. http://dx.doi.org/10.7202/1000048ar.

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Cores from tops of seamounts close to the continental shelf west of the Grand Banks contain sequences of alternating clays (representing glacials) and foram nanno ooze (deposited in warmer periods), back to the Pliocene. Although sedimentation in the cores is controlled primarily by glacial conditions on the Grand Banks and Laurentian Channel, glacial history further inland can be inferred. The Wisconsin sequence shows two cool interstadials and one rather warmer one, correlable with the Plum Point, Port Talbot and St. Pierre Interstadials. Clay sedimentation during Wisconsin glacial stages was minor, suggesting glaciers did not extend to the shelf edge. In the late lllinoian, there was a major influx of red sediments, indicating significant erosion of the Gulf of St. Lawrence and Laurentian Channel. Glaciation was more extensive than during the Wisconsin. Two lllinoian interstadials, with temperatures between those of the Plum Point and St. Pierre interstadials are recognised. Early lllinoian glaciation was the most severe yet recognised in the cores. Sedimentation appears to have been controlled by the advance of a Newfoundland — Labrador — E. Québec ice sheet across the Grand Banks.

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Lemmen, Donald S., Robert Gilbert, John P. Smol, and Roland I. Hall. "Holocene sedimentation in glacial Tasikutaaq Lake, Baffin Island." Canadian Journal of Earth Sciences 25, no. 6 (June 1, 1988): 810–23. http://dx.doi.org/10.1139/e88-080.

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Tasikutaaq Lake, on Cumberland Peninsula, Baffin Island, receives inflow and fine sediment from a 448 km2 drainage basin, 21% of which is glacier covered. During the summer of 1983 the lake remained essentially isothermal between about 4 and 6 °C. The suspended sediment concentration of inflow never exceeded 100 mg L−1 with overflow and homopycnal flow dominant.Surface sediments are clearly laminated, although varves are not apparent. The sediments are very fine, with less than 3% sand in all but the most proximal sites. Average sedimentation rates between 1976 and 1983 ranged from about 4 mm a−1 to 0.25 mm a−1 down lake from the point of inflow. The absence of varves is a function of the low rates of sediment accumulation and the long residence time of the fine sediments in the water column.Three sediment cores up to 135 cm in length reveal marked changes in sediment characteristics and diatom assemblages through the Holocene. During the late Foxe Glaciation it is likely that glacier ice contacted the lake, with retreat upvalley recorded by thinly varved (?) silts. By 7580 ± 140 BP ice had retreated to near its present margins. The earliest diatom assemblage in the cores is dominated by small Fragilaria spp., typical of late glacial, pioneering environments. Sedimentation rates during much of the Hypsithermal were about five times less than at present, with the resulting massive sediments having "nonglacial" characteristics despite the presence of glacial ice in the drainage basin. A planktonic diatom flora suggests that summer lake ice cover was minimal at this time. A climatic deterioration at about 4500 BP marks the onset of the Neoglacial, recorded by a shift in the diatom assemblage to species characteristic of more shallow water environments. Retreat from Neoglacial moraines is recorded by clearly laminated sediments and increasing accumulation rates. In general, laminated sediments relate to periods of high sediment input associated with glacial retreat, whereas massive sediments relate to low sediment input in association with glacial stabilization or advance.

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9

Leonard, Eric M. "Use of Lacustrine Sedimentary Sequences as Indicators of Holocene Glacial History, Banff National Park, Alberta, Canada." Quaternary Research 26, no. 2 (September 1986): 218–31. http://dx.doi.org/10.1016/0033-5894(86)90106-7.

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Bottom sediments from three lakes in the Canadian Rocky Mountains were examined with the aim of evaluating the usefulness of downvalley sediment studies in reconstruction of Holocene glacial histories. Analyses of organic carbon and carbonate contents of core sediments provide information on changing sedimentation rate and changing relative importance of glacial and non-glacial sediment sources. Sedimentary histories of the three lakes are similar, suggesting that they record regional glacial/climatic forcing, rather than localized events, and thus that they may be useful in reconstructing Holocene glacial history. Lacustrine sediments indicate a period of high sedimentation rates and relatively large glacial sediment contribution prior to 7500-7000 yr B.P., with much reduced rates and decreased glacial sediment contribution between about 6000 and 4000 yr B.P., possibly interrupted by a brief period of increased glacial sediment output shortly after 5000 yr B.P. Sometime after 4000 yr B.P., sedimentation rates and glacial sediment output began to rise again, reaching approximately present levels by 2750-2650 yr B.P., and have not since returned to low mid-Holocene levels. In detail over the last 3000 yr there is some indication of a slight decrease in sedimentation rate for more than 1000 yr after about 2200 yr B.P. Sedimentation rates and glacial sediment input into all three lakes rose between about 900 and 750 yr B.P. and have remained very high since. If the lake sediments are interpreted as a proxy record of upvalley glacial activity, they allow the development of a glacial chronology which is at once generally consistent with, and more complete and easily datable than, the surficial glacial record.

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Leonard, Eric M. "Varve Studies at Hector Lake, Alberta, Canada, and the Relationship Between Glacial Activity and Sedimentation." Quaternary Research 25, no. 2 (March 1986): 199–214. http://dx.doi.org/10.1016/0033-5894(86)90057-8.

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Glacial lake sedimentary records from Hector Lake in Banff National Park, Alberta, are examined with the aim of clarifying the relationship between glacial activity and outwash sedimentation. Rhythmic couplets in lake bottom sediments provide a method for accurate documentation and dating of recent sedimentation chronology, as analysis of 137Cs content indicates that the couplets are of annual periodicity (i.e., varves). A comparison of sedimentation rate records with recent regional glacial history indicates that high sedimentation rates of one to a few decades duration occur either during and immediately following periods of moraine deposition (ie, maximum ice stands) or during periods of rapid ice recession. Comparison of sedimentary records with somewhat longer term glacial and vegetation records indicates that sedimentation rate variations of several centuries duration closely parallel changes in upvalley ice extent. Over this time scale, high sedimentation rates occur during periods of relatively increased ice extent, low rates during periods of reduced ice extent. Within this general pattern, however, sedimentation rates may remain very high for nearly a century following maximum ice stands, due to the exposure of unstable glaciogenic deposits to fluvial reworking during ice recession.

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11

van der Vegt, Paul. "Sedimentation in Pleistocene glacial tunnel valleys." Quaternary International 279-280 (November 2012): 513. http://dx.doi.org/10.1016/j.quaint.2012.08.1772.

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12

Hundert, Thian, and David J. W. Piper. "Late Quaternary sedimentation on the southwestern Scotian Slope, eastern Canada: relationship to glaciationGeological Survey of Canada Contribution 20070176." Canadian Journal of Earth Sciences 45, no. 3 (March 2008): 267–85. http://dx.doi.org/10.1139/e07-075.

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The sedimentary record on continental slopes has the potential to preserve a record of glacial retreat on the adjacent continental shelf. The glacial history of the southwestern part of the Scotian Shelf is poorly known. Air-gun and high-resolution sparker profiles and numerous sediment cores up to 10 m long have been used to determine the character of sedimentation on the southwestern Scotian Slope since the last glacial maximum (LGM). Seismic-reflection profiles show that glacial till was deposited at shallow depths on the upper continental slope, and correlation to dated piston cores farther downslope show that this till dates from the LGM. Slope sedimentation at this time was dominated by local ice and deposited as plume fallout and turbidites. Progressively increasing importance of red-brown sediment derived from glacial supply to Laurentian Channel indicates retreat of ice from the shelf edge and diminishing supply of proglacial sediment from the calving embayment in the mid-Scotian Shelf. With the termination of distal proglacial sediment supply, the sedimentation rate diminished rapidly and hemipelagic sedimentation prevailed through the Holocene.

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Epstein, O. G., A. G. Dlugach, and A. V. Starovoytov. "Late glacial glaciomarine and Holocene marine sediments in the eastern part of the Barents Sea: structure composition; thickness; conditions of formation." Moscow University Bulletin. Series 4. Geology, no. 3 (December 15, 2022): 83–88. http://dx.doi.org/10.33623/0579-9406-2022-3-83-88.

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Geological-geophysical dates are showing that Holocene marine and Late Glacial glaciomarine sediments in the eastern Barents Sea represent seismostratigraphic complexes (SSC), accordingly SSCI and SSCII. Th e composed of glacial mineral matter sediments SSCII formed in the time of the Barents Sea shelf deglaciation, but the sediments SSCI deposited in conditions of open marine basin and are terrigenious. Features of the structure, composition and thicknesses of sediments SSCII are defi nite by melting conditions of degraded glacier masses and by character of originated sedimentation basins, but of sediments SSCI — by hydrodynamic factor and, partially, — by processes of last glacial eustatic marine transgression.

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Hunter, Lewis E., Ross D. Powell, and Daniel E. Lawson. "Morainal-bank sediment budgets and their influence on the stability of tidewater termini of valley glaciers entering Glacier Bay, Alaska, U.S.A." Annals of Glaciology 22 (1996): 211–16. http://dx.doi.org/10.1017/s0260305500015445.

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Investigations of grounding-line sedimentation in front of tidewater termini of temperate valley glaciers demonstrate that sediment yields and dynamics provide a second-order control on glacier stability by influencing water depth at the grounding line. Sediment is delivered to the grounding line by two routes: (1) debris transported in, on and beneath the glacier, and (2) sediment transported in glacial outwash streams. Glacial streams in Glacier Bay, Alaska, U.S.A., deliver 106to 107m3year−1of sediment to the grounding lines. The glacial debris flux transports 105to 106m3year−1of debris to the ice cliffs, where approximately 10% is released at the grounding line, the remainder being transported downfjord by iceberg-rafting. An additional 105m3year−1of sediment may be transported to the grounding line by shearing and advection of a deformable bed.

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Hunter, Lewis E., Ross D. Powell, and Daniel E. Lawson. "Morainal-bank sediment budgets and their influence on the stability of tidewater termini of valley glaciers entering Glacier Bay, Alaska, U.S.A." Annals of Glaciology 22 (1996): 211–16. http://dx.doi.org/10.3189/1996aog22-1-211-216.

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Investigations of grounding-line sedimentation in front of tidewater termini of temperate valley glaciers demonstrate that sediment yields and dynamics provide a second-order control on glacier stability by influencing water depth at the grounding line. Sediment is delivered to the grounding line by two routes: (1) debris transported in, on and beneath the glacier, and (2) sediment transported in glacial outwash streams. Glacial streams in Glacier Bay, Alaska, U.S.A., deliver 106 to 107 m3 year−1 of sediment to the grounding lines. The glacial debris flux transports 105 to 106 m3 year−1 of debris to the ice cliffs, where approximately 10% is released at the grounding line, the remainder being transported downfjord by iceberg-rafting. An additional 105 m3 year−1 of sediment may be transported to the grounding line by shearing and advection of a deformable bed.

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Barnett, Peter J., and Paul F. Karrow. "Ice-marginal sedimentation and processes of diamicton deposition in large proglacial lakes, Lake Erie, Ontario, Canada." Canadian Journal of Earth Sciences 55, no. 7 (July 2018): 846–62. http://dx.doi.org/10.1139/cjes-2017-0006.

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Detailed studies of coastal cliff exposures through two end moraines form the basis for a model of ice-marginal sedimentation in large ice-contact glacier-fed lakes. The input to the ice-marginal environment directly from the glacier included subglacial till and subaquatic flow tills. The subaquatic flow till (thinly bedded diamicton) was deposited in an apron (up to 1 km wide) along the ice margin. An upward gradient of pore-water pressure immediately beyond the ice margin, causing heaving and dilation of the sediments, initiated debris flows of glacially derived debris (subaquatic flow tills). Most of the stratified sediments in the ice-marginal zone entered the lake by way of a large proglacial stream. Sedimentation was dominated by quasi- or near-continuous density underflows that resulted in the deposition of a sequence of thick rhythmites. The glacier in the Lake Erie basin most likely behaved like an ice stream, with its movement controlled predominantly by a deforming bed of glacial debris, separating the glacier sole from underlying predeposited sediments. The deforming bed is preserved as a massive diamicton layer, interpreted here as subglacially deposited till.

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Jamšek Rupnik, Petra, Manja Žebre, and Giovanni Monegato. "Late Quaternary evolution of the sedimentary environment in Modrejce near Most na Soči (Soča Valley, Julian Alps)." Geologija 63, no. 2 (December 7, 2020): 295–309. http://dx.doi.org/10.5474/geologija.2020.022.

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Geomorphological and geological mapping have long been used to study the glacial history of the Slovenian Alps, but many uncertainties remain regarding the time and extent of Pleistocene glaciations there. Glacial landforms and undisturbed glacial deposits are rare in the areas of the former glacier terminus, especially in the Soča Valley, where large discrepancies in the interpretation of the extent of the former Soča Glacier have been reported. Early studies proved inconclusive as to whether one or two glaciations extended into the Soča Valley as far as Most na Soči. In order to answer this question, the Quaternary sedimentary succession and landforms in the Modrejce Valley near Most na Soči were investigated. New geological and geomorphological field data allow the interpretation of the sedimentary environment and the stratigraphic relationships between different units. In response to glacial dynamics, the sedimentation developed from glaciofluvial and glaciolacustrine to fully glacial environments, followed by slope deposition. At higher altitudes lateral moraines are preserved, while the staircase-like slope below has been carved into older glacial, glaciofluvial and glaciolacustrine deposits by glacial and post-glacial processes, including fluvial erosion and slope dynamics. We conclude that the succession studied here was deposited over the course of two different glacial advances – LGM and pre-LGM. Our study thus suggests that the Soča Glacier extended as far as the area of Most na Soči twice over the course of the late Quaternary.

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Lemoine, Rick M., and James T. Teller. "Late Glacial Sedimentation and History of the Lake Nipigon Basin, Ontario." Géographie physique et Quaternaire 49, no. 2 (November 30, 2007): 239–50. http://dx.doi.org/10.7202/033039ar.

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ABSTRACTThe Lake Nipigon basin lies north of the Lake Superior basin and was the hydrological link between glacial Lake Agassiz and the Great Lakes during part of the last deglaciation. A sequence of glaciolacustrine sediments, composed mainly of silt-clay rhythmites and sand, was deposited in the offshore waters of glacial Lake Nipigon by overflow from Lake Agassiz and meltwater from the retreating glacier margin. Sections from six long sediment cores and four lake bluff exposures reveal a sandy (early deglacial) lower section that is overlain by 300 to 850 silt-clay rhythmites (varves). Deposition of these varves, as well as coarser sediment along the western shore, began after 9200 BP, as the glacial margin retreated northward along the continental divide that separated the Nipigon basin from the higher Lake Agassiz basin to the west. The absence of ice rafted clasts in the rhythmites suggests that the ice had retreated from the lake by the time they were deposited. On the basis of their elevation in relation to the lowest raised beach at West Bay, which formed about 9000 BP, most rhythmites probably were deposited between 9000 and 8000 BP. Species of arboreal pollen are present in early postglacial sediments of the Nipigon-Superior lowlands, suggesting that the Lake Nipigon region became colonized by coniferous and deciduous forests soon after déglaciation. The presence of non-arboreal pollen species suggest that these forests were interspersed with open meadows and grasslands, similar to today's floral assemblages. Fossil molluscs recovered from glaciolacustrine sand exposed along the eastern side of the basin suggest that the limnological characteristics of late glacial Lake Nipigon were similar to those of today.

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Kennedy, Douglas S., and John B. Anderson. "Glacial-Marine Sedimentation and Quaternary Glacial History of Marguerite Bay, Antarctic Peninsula." Quaternary Research 31, no. 2 (March 1989): 255–76. http://dx.doi.org/10.1016/0033-5894(89)90008-2.

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AbstractMarguerite Bay, situated between the subpolar glacial regime of the northern Antarctic Peninsula and the polar glacial regime of West Antarctica, is ideally located to test various models of glacial and glacial-marine sedimentation and specific scenarios of late Wisconsin ice sheet expansion. Piston cores and single-channel seismic reflection data were collected during the Deep Freeze 85 and 86 expeditions to determine the late Quaternary history of the area. Seismic data in the bay show a rugged seafloor, with numerous deep troughs and a very thin layer of sediment over crystalline basement or older sediments. Glacial erosion is important in modifying existing features, although the ultimate repository of the eroded material is not known; it is not found within the bay. The piston cores are topped by diatomaceous muds, which are underlain by terrigenous muds and muddy gravels that imply deposition beneath an ice shelf. Basal tills were penetrated at three sites, reflecting deposition by a grounded marine ice sheet. A reconstruction of the glacial history of Marguerite Bay since the last glacial maximum shows grounded ice filling the bay in late Wisconsin time. Rising sea level caused an uncoupling of the ice sheet and slow retreat of an ice shelf throughout the Holocene.

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Guyard, Hervé, Pierre Francus, Guillaume St-Onge, Sonja Hausmann, and Reinhard Pienitz. "Microfacies and microstructures of subglacial and deglacial sediments from the Pingualuit Crater Lake (Ungava Peninsula, Canada)." Canadian Journal of Earth Sciences 51, no. 12 (December 2014): 1084–96. http://dx.doi.org/10.1139/cjes-2014-0041.

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The Pingualuit Crater (Ungava Peninsula, Canada) hosts a freshwater basin in which a subglacial lake subsisted under the Laurentide Ice Sheet during the last glacial period. Microfacies and microstructures of a 9 m long sediment core are presented to discuss the depositional environment of deformed glacigenic and postglacial sequences deposited in the deep basin of the lake. Five distinct lithofacies are characterized. The range of glacial microstructures observed in the lower facies (Facies IV) reveals that high stress level occurred outside the crater during the formation of this diamicton released by the ablation of debris-rich basal glacier ice in an ice contact subglacial–proglacial lacustrine environment. The overlying subaqueous and glacigenic sediment gravity flow (Facies IIIb) is associated with a temporary absence of ice cover over the coring site, and likely results from the efflux plume and the associated suspension sedimentation produced during the retreat of the ice margin. Then, the finely laminated (<1–2 mm) and normally graded meltout silts (Facies IIIa) containing dropstones and load cast features suggest underflows in an unstable ice marginal lacustrine environment hydrologically separated from the retreating glacier but containing floating glacial ice blocks. Microstructures within occasional diamictic layers indicate sudden meltout deposits from these drifting ice blocks. The above finer-grained sediments (Facies Ib) lack typical glacial microstructures, marking the onset of postglacial organic sedimentation. These postglacial sediments are affected by post-depositional deformations due to an overlying rotational slide (Facies II) that may have perturbed the associated environmental record.

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BOLDT LOVE, KATHERINE, BERNARD HALLET, THOMAS L. PRATT, and SHAD O'NEEL. "Observations and modeling of fjord sedimentation during the 30 year retreat of Columbia Glacier, AK." Journal of Glaciology 62, no. 234 (May 31, 2016): 778–93. http://dx.doi.org/10.1017/jog.2016.67.

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ABSTRACTTo explore links between glacier dynamics, sediment yields and the accumulation of glacial sediments in a temperate setting, we use extensive glaciological observations for Columbia Glacier, Alaska, and new oceanographic data from the fjord exposed during its retreat. High-resolution seismic data indicate that 3.2 × 108m3of sediment has accumulated in Columbia Fjord over the past three decades, which corresponds to ~5 mm a−1of erosion averaged over the glaciated area. We develop a general model to infer the sediment-flux history from the glacier that is compatible with the observed retreat history, and the thickness and architecture of the fjord sediment deposits. Results reveal a fivefold increase in sediment flux from 1997 to 2000, which is not correlated with concurrent changes in ice flux or retreat rate. We suggest the flux increase resulted from an increase in the sediment transport capacity of the subglacial hydraulic system due to the retreat-related steepening of the glacier surface over a known subglacial deep basin. Because variations in subglacial sediment storage can impact glacial sediment flux, in addition to changes in climate, erosion rate and glacier dynamics, the interpretation of climatic changes based on the sediment record is more complex than generally assumed.

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Giraudi, Carlo. "Middle to Late Holocene glacial variations, periglacial processes and alluvial sedimentation on the higher Apennine massifs (Italy)." Quaternary Research 64, no. 2 (September 2005): 176–84. http://dx.doi.org/10.1016/j.yqres.2005.06.007.

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AbstractThe major climatic variations that have affected the summit slopes of the higher Apennine massifs in the last 6000 yr are shown in alternating layers of organic matter-rich soils and alluvial, glacial and periglacial sediments. The burial of the soils, triggered by environmental–climatic variations, took place in several phases. For the last 3000 yr chronological correlations can be drawn between phases of glacial advance, scree and alluvial sedimentation and development of periglacial features. During some periods, the slopes were covered by vegetation up to 2700 m and beyond, while in other phases the same slopes were subject to glacial advances and periglacial processes, and alluvial sediments were deposited on the high plateaus. Around 5740–5590, 1560–1370 and 1300–970 cal yr B.P., organic matter-rich soils formed on slopes currently subject to periglacial and glacial processes; the mean annual temperature must therefore have been higher than at present. Furthermore, on the basis of the variations in the elevation of the lower limit reached by gelifraction, it can be concluded that the oscillations in the minimum winter temperatures could have ranged between 3.0°C lower (ca. 790–150 cal yr B.P.) and 1.2°C higher (ca. 5740–5590 cal yr B.P.) than present minimum winter temperatures. During the last 3000 yr the cold phases recorded by the Calderone Glacier advance in the Apennines essentially match basically the phases of glacial advance in the Alps.

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Kim, Ju Yong. "Last Glacial Fluvial Sedimentary Sequences and Sedimentation Rate." Quaternary International 279-280 (November 2012): 244. http://dx.doi.org/10.1016/j.quaint.2012.08.568.

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Hogan, Kelly A., Martin Jakobsson, Larry Mayer, Brendan T. Reilly, Anne E. Jennings, Joseph S. Stoner, Tove Nielsen, et al. "Glacial sedimentation, fluxes and erosion rates associated with ice retreat in Petermann Fjord and Nares Strait, north-west Greenland." Cryosphere 14, no. 1 (January 28, 2020): 261–86. http://dx.doi.org/10.5194/tc-14-261-2020.

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Abstract. Petermann Fjord is a deep (>1000 m) fjord that incises the coastline of north-west Greenland and was carved by an expanded Petermann Glacier, one of the six largest outlet glaciers draining the modern Greenland Ice Sheet (GrIS). Between 5 and 70 m of unconsolidated glacigenic material infills in the fjord and adjacent Nares Strait, deposited as the Petermann and Nares Strait ice streams retreated through the area after the Last Glacial Maximum. We have investigated the deglacial deposits using seismic stratigraphic techniques and have correlated our results with high-resolution bathymetric data and core lithofacies. We identify six seismo-acoustic facies in more than 3500 line kilometres of sub-bottom and seismic-reflection profiles throughout the fjord, Hall Basin and Kennedy Channel. Seismo-acoustic facies relate to bedrock or till surfaces (Facies I), subglacial deposition (Facies II), deposition from meltwater plumes and icebergs in quiescent glacimarine conditions (Facies III, IV), deposition at grounded ice margins during stillstands in retreat (grounding-zone wedges; Facies V) and the redeposition of material downslope (Facies IV). These sediment units represent the total volume of glacial sediment delivered to the mapped marine environment during retreat. We calculate a glacial sediment flux for the former Petermann ice stream as 1080–1420 m3 a−1 per metre of ice stream width and an average deglacial erosion rate for the basin of 0.29–0.34 mm a−1. Our deglacial erosion rates are consistent with results from Antarctic Peninsula fjord systems but are several times lower than values for other modern GrIS catchments. This difference is attributed to fact that large volumes of surface water do not access the bed in the Petermann system, and we conclude that glacial erosion is limited to areas overridden by streaming ice in this large outlet glacier setting. Erosion rates are also presented for two phases of ice retreat and confirm that there is significant variation in rates over a glacial–deglacial transition. Our new glacial sediment fluxes and erosion rates show that the Petermann ice stream was approximately as efficient as the palaeo-Jakobshavn Isbræ at eroding, transporting and delivering sediment to its margin during early deglaciation.

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Tomkins, Jessica D., and Scott F. Lamoureux. "Multiple hydroclimatic controls over recent sedimentation in proglacial Mirror Lake, southern Selwyn Mountains, Northwest Territories." Canadian Journal of Earth Sciences 42, no. 9 (September 1, 2005): 1589–99. http://dx.doi.org/10.1139/e05-049.

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Varves from Mirror Lake, Northwest Territories (62°N, 128°W) reveal significant, but changing climatic influences on discharge and sedimentation on a decadal scale during the late 20th century. The complex hydroclimatic signal within the sediments indicates the difficulty in identifying a quantitative relationship between varve thickness and a single climatic variable. Regression of recent varve thickness with local meteorological data shows July temperature as the dominant control over sediment accumulation. In contrast, the dampening effects of increased snowfall on glacier ablation and resultant runoff reduce sediment delivery. Although the impact of snowfall does not appear to significantly weaken the relationship between summer temperature and varve formation, periods when multiple climatic factors control sediment delivery are characterized by distinctive varves containing two prominent silt units. Thus, the Mirror Lake hydrological system appears to shift between two general states. The first state involves a pronounced summer glacial meltwater phase due to dominant summer temperature influences on glacial melt, resulting in varves with one silt unit. This varve structure dominates the sedimentary record from A.D. 1670 to 1941, possibly reflecting a Little Ice Age influence in the study area. The second state operates in years when glacial meltwater discharge is delayed until August, due to increased snow cover, and the lake receives increased sediment-poor nival melt. These conditions lead to the formation of varves with two silt units corresponding to nival and glacial discharge phases and are common in the sedimentary record from A.D. 1390 to 1669 and A.D. 1942 to 1996.

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26

Bard, Edouard, Laurent Labeyrie, Maurice Arnold, Monique Labracherie, Jean-Jacques Pichon, Josette Duprat, and Jean-Claude Duplessy. "AMS-14C Ages Measured in Deep Sea Cores from the Southern Ocean: Implications for Sedimentation Rates during Isotope Stage 2." Quaternary Research 31, no. 2 (March 1989): 309–17. http://dx.doi.org/10.1016/0033-5894(89)90011-2.

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Abstract14C dates obtained by accelerator mass spectrometry (AMS) on monospecific foraminiferal samples from two deep-sea sediment cores raised in the Indian sector of the Southern Ocean have been corrected for the difference in 14C composition between atmosphere and sea surface by using a reconstruction of the latitudinal 14C gradient which existed in the Southern Ocean prior to 1962. The corrected AMS-14C data show a reduced sedimentation rate in core MD 84-527 between 25,000 and 10,000 yr BP. For core MD 84-551 the available data suggest that the sedimentation rate was higher during the Holocene than during the glacial period. These changes in sedimentation rates may be attributed to an increased opal dissolution during the last glacial maximum.

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27

Hepp, Daniel A., and Tobias Mörz. "An approach to quantifying Pliocene ice sheet dynamics via slope failure frequencies recorded in Antarctic Peninsula rise sediments." Antarctic Science 21, no. 6 (July 17, 2009): 619–31. http://dx.doi.org/10.1017/s0954102009990289.

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AbstractUnderstanding of glacially driven sedimentary transport systems across the shelf to the slope and subsequently to deep sea sediment bodies along the Pacific continental margin of Antarctic Peninsula is crucial for interpreting ice sheet dynamics. Here we quantify slope-failure frequencies recorded in Pliocene core intervals of ODP Site 1095. We used the relationship between long-term sedimentation rate and marine carbon burial efficiency to calculate glacial or interglacial specific sedimentation rates. Using the decompacted average length of glacial-interglacial cycles it was possible to solve a set of linear equations to derive average half-periods of 61.59 and 59.77 kyr respectively for the time interval 5.8–3.2 Ma. The resulting frequency distribution of slope failures reflects short and rapid but cyclic ice advances every ∼375 years. Short retention times between slope loading and slope failure are supported by biogenic silica dissolution analyses. This study demonstrates the potential of the rise record to improve models of orbitally controlled size variations of the West Antarctic ice sheet and confirms the hypothesis of a highly dynamic ice sheet during the early Pliocene warm period.

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Batchelor, C. L., J. A. Dowdeswell, K. A. Hogan, R. D. Larter, E. Parsons, and O. West. "Processes and patterns of glacier-influenced sedimentation and recent tidewater glacier dynamics in Darbel Bay, western Antarctic Peninsula." Antarctic Science 31, no. 4 (May 14, 2019): 218–27. http://dx.doi.org/10.1017/s0954102019000191.

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AbstractBathymetric data of unprecedented resolution are used to provide insights into former ice dynamics and glacial processes in a western Antarctic Peninsula embayment. An assemblage of submarine glacial landforms, which includes subglacially produced streamlined features and ice-marginal ridges, reveals the former pattern of ice flow and retreat. A group of more than 250 small (< 1–3 m high, 10–20 m wide) and relatively evenly spaced recessional moraines was identified beyond the margin of Philippa Glacier. The small recessional moraines are interpreted to have been produced during short-lived, possibly annual re-advances of a grounded ice margin during overall retreat. This is the first time that these features have been shown to be part of the assemblage of landforms produced by tidewater glaciers on the Antarctic Peninsula. Glacier-terminus changes during the last four decades, mapped from LANDSAT satellite images, were analysed to determine whether the moraines were produced during recent still-stands or re-advances of Philippa Glacier and to further investigate the short-term (annual to decadal) variability in ice-marginal position in tidewater glacier systems. The asynchronous response of individual tidewater glaciers in Darbel Bay is interpreted to be controlled mainly by local topography rather than by glacier catchment-area size.

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29

Henderson, Penny J. "Sedimentation in an esker system influenced by bedrock topography near Kingston, Ontario." Canadian Journal of Earth Sciences 25, no. 7 (July 1, 1988): 987–99. http://dx.doi.org/10.1139/e88-098.

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Late Wisconsinan sand and gravel deposits on the Frontenac Arch, Ontario, record a major meltwater drainage system developed subglacially and subaqueously in one or more glacial lake phases of the Lake Ontario basin during retreat of the Laurentide Ice Sheet. Factors influencing channel location, morphology, and sediment deposition are ice flow direction and the Precambrian bedrock topography, in turn dependent upon bedrock structure and composition. Meltwater drainage across the Frontenac Arch is localized within a broad depression oriented approximately parallel to glacial flow. Sediment deposition within the regional depression follows ice-flow direction despite irregular bedrock relief, indicating formation of the meltwater system and associated sediments in three stages: (i) establishment of a continuous meltwater system subglacially under high hydrostatic pressure with minor erosion of underlying Precambrian bedrock; (ii) deposition of poorly sorted, coarse-grained sediment in cavities or channels associated with irregular bedrock topography; and (iii) deposition of several coalescing subaqueous outwash fans at the ice margin as the glacier receded from the area. The discontinuous nature of the deposits and the association of proximal to distal outwash fan facies within a deposit suggest that esker sedimentation occurred during periodic stabilization of the ice front during deglaciation.

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30

Webb, Nathan D., David A. Grimley, Andrew C. Phillips, and Bruce W. Fouke. "Origin of glacial ridges (OIS 6) in the Kaskaskia Sublobe, southwestern Illinois, USA." Quaternary Research 78, no. 2 (July 20, 2012): 341–52. http://dx.doi.org/10.1016/j.yqres.2012.06.005.

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AbstractThe origin of Illinois Episode (OIS 6) glacial ridges (formerly: ‘Ridged Drift’) in the Kaskaskia Basin of southwestern Illinois is controversial despite a century of research. Two studied ridges, containing mostly fluvial sand (OSL ages: ~ 150 ± 19 ka), with associated debris flows and high-angle reverse faults, are interpreted as ice-walled channels. A third studied ridge, containing mostly fine-grained till, is arcuate and morainal. The spatial arrangement of various ridge types can be explained by a glacial sublobe in the Kaskaskia Basin, with mainly fine-grained ridges along the sublobe margins and coarse-grained glaciofluvial ridges in a paleodrainage network within the sublobe interior. Illinois Episode till fabric and striation data demonstrate southwesterly ice flow that may diverge near the sublobe terminus. The sublobe likely formed as glacial ice thinned and receded from its maximum extent. The Kaskaskia Basin contains some of the best-preserved Illinois Episode constructional glacial landforms in the North American midcontinent. Such distinctive features probably result from ice flow and sedimentation into this former lowland, in addition to minimal postglacial erosion. Other similar OIS 6 glacial landforms may exist in association with previously unrecognized sublobes in the midcontinent, where paleo-lowlands might also have focused glacial sedimentation.

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31

Frakes, L. A. "A preliminary model for subaqueous-glacial and post-glacial sedimentation in intra-continental basins." Palaeogeography, Palaeoclimatology, Palaeoecology 51, no. 1-4 (October 1985): 347–56. http://dx.doi.org/10.1016/0031-0182(85)90092-6.

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32

Aksu, A. E., and David J. W. Piper. "Late Quaternary sedimentation in Baffin Bay." Canadian Journal of Earth Sciences 24, no. 9 (September 1, 1987): 1833–46. http://dx.doi.org/10.1139/e87-174.

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Baffin Bay is a small ocean basin that connects the Arctic and Atlantic oceans. The adjacent continental shelves have been extensively reworked during Quaternary glaciation. The shelf break generally lies between 200 and 500 m. The continental slope passes directly into the abyssal plain of Baffin Bay basin without any major submarine canyon – deep-sea fan system being present, except for a large smooth sediment apron in northern Baffin Bay.On the basis of over 50 piston cores, six Quaternary sediment facies are distinguished from detrital mineralogy (reflected in colour) and sediment texture. Facies A, B, and C are predominantly ice-rafted or are debris flow deposits, each with a distinct mineralogy. Facies D is turbidites and bottom-current sorted sands, silts, and muds. Facies E is hemipelagic sediment. Facies F consists of sediments ranging from slumps, through debris flow deposits, to fine-grained turbidites, with a distinctive provenance in northern Baffin Bay.These sediment facies appear to be partly controlled by glacial conditions. Hemipelagic facies E predominates during the present interglacial. During glacial stages, facies D turbidites were deposited. They resulted from slumping of proglacial sediments on the continental slopes off Greenland and Baffin Island. Facies C and F occurred on the continental slopes at these times. Ice-rafted facies A and B predominate at several horizons, reflecting a rapid breakup of ice shelves in northern Baffin Bay and increased rates of iceberg melting within the Bay. Overall sedimentation rates are relatively low, reflecting dry-base ice sheets in source areas.Deep-sea channel systems floored by sorted coarse sediments and bounded by muddy levees are absent in Baffin Bay, in contrast to mid-latitude glaciated continental margins off eastern Canada. These channel systems are the result of melting of wet-base glaciers, which provide a localized supply of sediment that is sorted by ice margin processes. In Baffin Bay, most glacial sediments are derived by calving of icebergs, probably from dry-base glaciers. Sediments are gradually released over large areas as the bergs melt, and are subsequently redistributed by debris flows.

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33

Piper, David J. W., Peta J. Mudie, Ali E. Aksu, and Philip R. Hill. "Late Quaternary sedimentation, 50° N, North-East Newfoundland shelf." Géographie physique et Quaternaire 32, no. 4 (January 25, 2011): 321–32. http://dx.doi.org/10.7202/1000331ar.

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Ten cores from the Northeast Newfoundland shelf and adjacent continental slope have correlable late Quaternary marine sequences. Late Holocene sediment is olive grey mud, with some ice-rafted debris. The early Holocene is characterised by warmer water microfossil assemblages, abundant ice-rafted carbonate debris, and pollen assemblages indicating open boreal woodland interspersed with tundra. Late and mid-Wisconsinan glacial stades show subarctic planktonic microfossil assemblages, regional sources of tundra pollen, storm reworking of earlier sediment, including till, and shallower water assemblages of benthonic foraminifera and diatoms. Two mid-Wisconsinan interstades are recognised, with marine microfossils similar to the early Holocene. This sequence rests disconformably on earlier (?lllinoian) pro-glacial muds which appear to overlie till.

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34

Mothersill, John S. "Paleomagnetic dating of late glacial and postglacial sediments in Lake Superior." Canadian Journal of Earth Sciences 25, no. 11 (November 1, 1988): 1791–99. http://dx.doi.org/10.1139/e88-169.

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The oldest unit of the late Quaternary sedimentary sequence of Lake Superior consists of glacial till that was deposited about 9900 years BP during the last glacial readvance into the Lake Superior basin. The till deposits are unconformably overlain by a thin sequence of bedded sands and silts, which are overlain by a thick sequence of varved sediments (> 10 m in thickness), which in turn are overlain by postglacial silty clays.Unfortunately, 14C has not been found to be a useful tool in dating the late glacial and postglacial sediments of Lake Superior. However, paleodeclination and paleoinclination logs provide a useful method of correlating and indirectly dating cores taken of the late glacial and postglacial sediments. It is concluded from paleomagnetic dating that rhythmic sedimentation ceased before 9200 years BP in the southeastern lake proper and at about 8700 years BP in the southeastern bay areas. However, rhythmic sedimentation continued until about 8200 years BP in the northern part of Lake Superior and until about 8000 years BP in the Nipigon Bay area.

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35

Viviani, Juliana B., Antonio C. Rocha-Campos, and Marcia Ernesto. "Late paleozoic glacial sedimentation in Northeastern Brazil: new results." Anais da Academia Brasileira de Ciências 72, no. 4 (December 2000): 598. http://dx.doi.org/10.1590/s0001-37652000000400012.

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36

Udalov, A. A., A. A. Vedenin, A. I. Chava, and S. A. Schuka. "Benthic fauna of the Oga Bay (Novaya Zemlya, Kara Sea)." Океанология 59, no. 6 (December 22, 2019): 1028–38. http://dx.doi.org/10.31857/s0030-15745961028-1038.

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Benthic fauna of the Oga Bay (the Kara Sea, Novaya Zemlya) was studied in 20152016 during the IO RAS expeditions on RV "Akademik Mstislav Keldysh". 5 grab stations (15 samples) at depths of 70140 m were sampled. Three macrobenthic communities consecutively replaced each others from the inner near-glacier part of the gulf towards the outher slope. The main factor determining the distribution of macrobenthic communities in the Oga Bay is the concentration of suspended matter in the water column and in the near-bottom layer, that caused by a very powerful level of sedimentation from the Goluboy (Oga) glacier. The depletion of benthic communities (qualitative and quantitative) which is typical for Arctic fjords with glacial inflow was shown. The specific community with the dominance of bivalve Portlandia arctica inhabits the main part of the bay. The peculiarities of the benthos of Arctic glacial bays are discussed.

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37

Houben, Peter. "Late-glacial and Holocene fluvial sedimentation in a small upland catchment in Hesse (Germany)." Zeitschrift für Geomorphologie 41, no. 4 (December 26, 1997): 461–78. http://dx.doi.org/10.1127/zfg/41/1997/461.

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38

PIRRIE, D., J. A. CRAME, J. B. RIDING, A. R. BUTCHER, and P. D. TAYLOR. "Miocene glaciomarine sedimentation in the northern Antarctic Peninsula region: the stratigraphy and sedimentology of the Hobbs Glacier Formation, James Ross Island." Geological Magazine 134, no. 6 (November 1997): 745–62. http://dx.doi.org/10.1017/s0016756897007796.

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The onshore record of Cenozoic glaciation in the Antarctic Peninsula region is limited to a number of isolated localities on Alexander Island, the South Shetland Islands and in the James Ross Island area. In the James Ross Island area, Late Cretaceous sedimentary rocks are unconformably overlain by a unit of diamictites and tuffs, which occur at the base of the James Ross Island Volcanic Group. These rocks are here defined as the Hobbs Glacier Formation, and on the basis of palynological studies are assigned to a Miocene (?late Miocene) age. The diamictites are interpreted as representing glaciomarine sedimentation close to the grounding line of either a floating ice shelf or a grounded tidewater glacier in a marine basin. Provenance studies indicate that the glacier was flowing from the Antarctic Peninsula towards the southeast. Volcanic tuffs conformably overlie the diamictites and are interpreted as representing deposition in a periglacial delta front setting in either a marine or non-marine basin, away from direct glacial influence. The Hobbs Glacier Formation and overlying James Ross Island Volcanic Group help to enhance our understanding of the Neogene glacial chronology of West Antarctica.

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39

Dupont, L. M., T. Caley, J. H. Kim, I. Castañeda, B. Malaizé, and J. Giraudeau. "Glacial-interglacial vegetation dynamics in South Eastern Africa coupled to sea surface temperature variations in the Western Indian Ocean." Climate of the Past 7, no. 4 (November 9, 2011): 1209–24. http://dx.doi.org/10.5194/cp-7-1209-2011.

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Abstract. Glacial-interglacial fluctuations in the vegetation of South Africa might elucidate the climate system at the edge of the tropics between the Indian and Atlantic Oceans. However, vegetation records covering a full glacial cycle have only been published from the eastern South Atlantic. We present a pollen record of the marine core MD96-2048 retrieved by the Marion Dufresne from the Indian Ocean ∼120 km south of the Limpopo River mouth. The sedimentation at the site is slow and continuous. The upper 6 m (spanning the past 342 Ka) have been analysed for pollen and spores at millennial resolution. The terrestrial pollen assemblages indicate that during interglacials, the vegetation of eastern South Africa and southern Mozambique largely consisted of evergreen and deciduous forests. During glacials open mountainous scrubland dominated. Montane forest with Podocarpus extended during humid periods was favoured by strong local insolation. Correlation with the sea surface temperature record of the same core indicates that the extension of mountainous scrubland primarily depends on sea surface temperatures of the Agulhas Current. Our record corroborates terrestrial evidence of the extension of open mountainous scrubland (including fynbos-like species of the high-altitude Grassland biome) for the last glacial as well as for other glacial periods of the past 300 Ka.

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40

Dupont, L. M., T. Caley, J. H. Kim, I. Castaneda, B. Malaizé, and J. Giraudeau. "Glacial-interglacial vegetation dynamics in south eastern Africa depend on sea surface temperature variations in the west Indian Ocean." Climate of the Past Discussions 7, no. 4 (July 6, 2011): 2261–96. http://dx.doi.org/10.5194/cpd-7-2261-2011.

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Abstract. Glacial-interglacial fluctuations in the vegetation of South Africa might elucidate the climate system at the edge of the tropics between Indian and Atlantic Ocean. However, vegetation records covering a full glacial cycle have only been published from the eastern South Atlantic. We present a pollen record of the marine core MD96-2048 retrieved by the Marion Dufresne from the Indian Ocean ~120 km south of the Limpopo River mouth. The sedimentation at the site is slow and continuous. The upper 6 m (down till 342 ka) have been analysed for pollen and spores at millennial resolution. The terrestrial pollen assemblages indicate that during interglacials the vegetation of eastern South Africa and southern Mozambique largely consisted of evergreen and deciduous forests. During glacials open mountainous scrubland dominated. Montane forest with Podocarpus extended during humid periods favoured by strong local insolation. Correlation with the sea surface temperature record of the same core indicates that the extension of mountainous scrubland primarily depends on sea surface temperatures of the Agulhas Current. Our record corroborates terrestrial evidence of the extension of open mountainous scrubland (including elements with affinity to the Cape Flora) for the last glacial as well as for other glacial periods of the past 300 ka.

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41

Bednarski, Jan. "The Geomorphology of Glaciomarine Sediments in a High Arctic Fiord." Géographie physique et Quaternaire 42, no. 1 (December 18, 2007): 65–74. http://dx.doi.org/10.7202/032709ar.

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ABSTRACTA general geomorphic model describing marine transgressions and regressions under non-glacial conditions is applied to the glacial environment. The general model recognizes two variables: i) the rate of relative sea level change, and ii) the rate of sedimentation at the coastline. The interaction of the two variables determines the nature of transgression or regression at a particular shoreline. In glaciated areas both sedimentation rates and relative sea level changes are controlled mainly by glacioclimatic responses of the ice. This is best illustrated along arctic coastlines where glacioisostatic loading caused extensive marine inundations during, and immediately after, the last glaciation. Subsequent emergence in the early Holocene has exposed extensive raised marine deposits. Clements Markham Inlet, on the northernmost coast of Ellesmere Island, Northwest Territories, contains raised marine deposits which have a definite spatial and sequential distribution related to the glacial history. The general geomorphic model is used to explain the distribution and geomorphology of this sediment. As the glacial cycle proceeds the balance between fluxes of sediment input and rate of sea level rise or fall will have a direct bearing on the type of stratigraphie sequence found in a particular area.

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42

Salomonsen, Inger. "Origin of a deep buried valley system in Pleistocene deposits of the eastern central North Sea." Danmarks Geologiske Undersøgelse Serie C 12 (December 31, 1995): 7–19. http://dx.doi.org/10.34194/seriec.v12.7106.

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In the North Sea, the sedimentary development of the late Tertiary and early Quaternary was dominated by deltaic sedimentation in a fast subsiding basin. During the Pleistocene, pronounced climatic changes affected the sedimentation of the area and progradation of the delta systems ceased. The Middle and Upper Pleistocene sedimentary successions consist of alternations of marine and fluvial deposits, partly reworked during glacial periods. Seismic records from the Danish sector of the North Sea reveal numerous deep incisions cut down from various levels of the Middle and Upper Pleistocene successions. These incisions are concluded to form a pattern of buried valleys. Detailed seismic stratigraphic analysis shows the occurrence of various internal unconformities within these buried valleys. It is concluded that the valleys originate from a river system developed in periods of repeated sea-level changes. Pluvial erosion during glacial sea-level lowstand and glacial meltwater action is proposed to have been responsible for the origin of the valley system. Thus, in Middle and Upper Pleistocene glacial periods drainage and associated sediment transport occurred from Northwest and Central European land areas via a presently buried river system in the southeastern North Sea towards a depositional basin north and northwest of the Danish North Sea sector.

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43

Håkanson, Lars. "A model to predict gross sedimentation in small glacial lakes." SIL Proceedings, 1922-2010 25, no. 1 (September 1993): 520. http://dx.doi.org/10.1080/03680770.1992.11900180.

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44

Arnaud, Emmanuelle, and Carolyn H. Eyles. "Glacial influence on Neoproterozoic sedimentation: the Smalfjord Formation, northern Norway." Sedimentology 49, no. 4 (August 2002): 765–88. http://dx.doi.org/10.1046/j.1365-3091.2002.00466.x.

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45

Montes, A. S. L., C. P. Gravenor, and M. L. Montes. "Glacial sedimentation in the late precambrian bebedouro formation, Bahia, Brazil." Sedimentary Geology 44, no. 3-4 (July 1985): 349–58. http://dx.doi.org/10.1016/0037-0738(85)90019-3.

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Håkanson, Lars. "A model to predict gross sedimentation in small glacial lakes." Hydrobiologia 284, no. 1 (May 1994): 19–42. http://dx.doi.org/10.1007/bf00005729.

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47

Xu, Mengzhen, Jim Bogen, Zhaoyin Wang, Truls E. Bønsnes, and Stine Gytri. "Pro-glacial lake sedimentation from jökulhlaups (GLOF), Blåmannsisen, northern Norway." Earth Surface Processes and Landforms 40, no. 5 (November 7, 2014): 654–65. http://dx.doi.org/10.1002/esp.3664.

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48

Andrews, John T. "Fiord to Deep Sea Sediment Transfers along the Northeastern Canadian Continental Margin: Models and Data." Géographie physique et Quaternaire 44, no. 1 (December 18, 2007): 55–70. http://dx.doi.org/10.7202/032798ar.

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ABSTRACT In Alaskan fiords, sedimentation rates are high; during a glacial advance fiord-basin sediments are transported to the ice front to form a shoal which reduces the calving rate. Thus, during successive glacial cycles, sediment is initially stored and then removed from fiord basins. In the fiords of eastern Baffin Island sedimentation rates are, and were, much lower (< 1000 Kg/m2 ka). and fiord-basin fills may span several glacial cycles. This hypothesis is in keeping with the relatively low sedimentation rates on the adjacent shelf (50 to 500 kg/m2 ka) and deep-sea plain (< = 50 kg/m2 ka). The advance of outlet glaciers through these arctic fiords may be explained by the in situ growth of a floating ice-shelf, grounded at the mouth of the fiord. The extent of late Foxe Glaciation in McBeth and ltirbilung fiords can be delimited by raised marine deltas (50-85 m asl) with 14C dates on in situ shells and whalebone of >54 ka. Holocene raised beaches are lower and date <10 ka. These data, plus the absence of tills in raised marine sections along the outer coast, make it difficult to extend grounded ice onto the shelf during the 18 ka global maximum. Piston cores from Tingin. ltirbilung and McBeth fiords vary between 4 and 11 m in length, but only sample a proportion of the total basin-fills.

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Winsor, Kelsey, Kate M. Swanger, Esther L. Babcock, James L. Dickson, Rachel D. Valletta, and Daniel F. Schmidt. "Origin, structure and geochemistry of a rock glacier near Don Juan Pond, Wright Valley, Antarctica." Antarctic Science 32, no. 4 (March 11, 2020): 273–87. http://dx.doi.org/10.1017/s0954102020000139.

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AbstractThe South Fork of Wright Valley contains one of the largest rock glaciers in the McMurdo Dry Valleys, Antarctica, stretching 7 km from the eastern boundary of the Labyrinth and terminating at Don Juan Pond (DJP). Here, we use results from ground-penetrating radar (GPR), qualitative field observations, soil leaching analyses and X-ray diffraction analyses to investigate rock glacier development. The absence of significant clean ice in GPR data, paired with observations of talus and interstitial ice influx from the valley walls, support rock glacier formation via talus accumulation. A quartz-dominated subsurface composition and discontinuous, well-developed desert pavements suggest initial rock glacier formation occurred before the late Quaternary. Major ion data from soil leaching analyses show higher salt concentrations in the rock glacier and talus samples that are close to hypersaline DJP. These observations suggest that DJP acts as a local salt source to the rock glacier, as well as the surrounding talus slopes that host water track systems that deliver solutes back into the lake, suggesting a local feedback system. Finally, the lack of lacustrine sedimentation on the rock glacier is inconsistent with the advance of a glacially dammed lake into South Fork during the Last Glacial Maximum.

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Barrie, J. Vaughn, H. Gary Greene, Kim W. Conway, and Daniel S. Brothers. "Late Quaternary sea level, isostatic response, and sediment dispersal along the Queen Charlotte fault." Geosphere 17, no. 2 (January 19, 2021): 375–88. http://dx.doi.org/10.1130/ges02311.1.

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Abstract The active Pacific margin of the Haida Gwaii and southeast Alaska has been subject to vigorous storm activity, dramatic sea-level change, and active tectonism since glacial times. Glaciation was minimal along the western shelf margin, except for large ice streams that formed glacial valleys to the shelf break between the major islands of southeast Alaska and Haida Gwaii. Upon deglaciation, sediment discharge was extensive, but it terminated quickly due to rapid glacial retreat and sea-level lowering with the development of a glacio-isostatic forebulge, coupled with eustatic lowering. Glacial sedimentation offshore ended soon after 15.0 ka. The shelf became emergent, with sea level lowering by, and possibly greater than, 175 m. The rapid transgression that followed began sometime before 12.7 ka off Haida Gwaii and 12.0 ka off southeast Alaska, and with the extreme wave-dominated environment, the unconsolidated sediment that was left on the shelf was effectively removed. Temperate carbonate sands make up the few sediment deposits presently found on the shelf. The Queen Charlotte fault, which lies just below the shelf break for most of its length, was extensively gullied during this short period of significant sediment discharge, when sediment was transported though the glacial valleys and across the narrow shelf through fluvial and submarine channels and was deposited offshore as sea level dropped. The Queen Charlotte fault became the western terminus of the glacio-isostatic forebulge, with the fault acting as a hinged flap taking up the uplift and collapse along the fault of 70+ m. This may have resulted in the development of the distinctive fault valley that presently acts as a very linear channel pathway for sediment throughout the fault system.

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Journal articles on the topic 'Glacial sedimentation'

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