scholarly journals Asynchronous development of two Late Glacial lake basins near the Drwęca ice-marginal valley (N Poland)

2017 ◽  
Vol 61 (2) ◽  
Author(s):  
Wojciech W. GAMRAT ◽  
Mirosław BŁASZKIEWICZ ◽  
Leon ANDRZEJEWSKI ◽  
Iwona KRZEŚLAK
Keyword(s):  
Late Glacial ◽  
Glacial Lake ◽  
Asynchronous Development ◽  
Lake Basins

scholarly journals A younger glacial Lake Iroquois in the Lake Ontario basin, Ontario and New York: re-examination of pollen stratigraphy and radiocarbon dating

2020 ◽  
Vol 57 (4) ◽  
pp. 453-463
Author(s):  
C.F.M. Lewis ◽  
T.W. Anderson
Keyword(s):  
New York ◽  
New York State ◽  
Lake Ontario ◽  
Late Glacial ◽  
Glacial Lake ◽  
Lake Basin ◽  
Long Distance ◽  
Small Lake ◽  
Pollen Stratigraphy ◽  
Lake Basins

Revision of palynochronologic and radiocarbon age estimates for the termination of glacial Lake Iroquois, mainly based on a currently accepted younger determination of the key Picea–Pinus pollen transition, shows agreement with recently established constraints for this late glacial event in the Lake Ontario basin at 13 000 cal years BP. The date of emergence or isolation of small lake basins reflects the termination of inundation by glacial lake waters. The increasing upward presence of plant detritus and the onset of organic sedimentation marks the isolation level in the sediments of a small lake basin. The upward relative decline and cessation of pollen from trees such as Pinus, Quercus, and other thermophilous hardwoods that were wind transported long distances from southern areas also mark the isolation of inundated small lake basins by the declining water level of Lake Iroquois as local vegetation grew and local pollen overwhelmed long-distance-transported pollen. Re-examination of data in small lake basins north of Lake Ontario using the above criteria shows that the age range for the termination of Lake Iroquois derived from these data overlaps other age constraints. These constraints are based on a varve-estimated duration of post-Iroquois phases before incursion of the Champlain Sea, a newly discovered late ice advance into northern New York State, and the age of a mastodon at Cohoes, New York. The new age (13 000 cal years BP) for Lake Iroquois termination is significantly younger than the previous estimate of 11 800 14C (13 600 cal) years BP.

scholarly journals Ice-marginal forced regressive deltas in glacial lake basins: geomorphology, facies variability and large-scale depositional architecture

Boreas ◽  
2018 ◽  
Vol 47 (4) ◽  
pp. 973-1002 ◽  
Author(s):  
Jutta Winsemann ◽  
Jörg Lang ◽  
Ulrich Polom ◽  
Markus Loewer ◽  
Jan Igel ◽  
...  
Keyword(s):  
Large Scale ◽  
Glacial Lake ◽  
Depositional Architecture ◽  
Lake Basins

The Middle Pleistocene of north Birmingham

1964 ◽  
Vol 247 (741) ◽  
pp. 533-592 ◽  
Keyword(s):  
Plant Communities ◽  
Deciduous Forest ◽  
Coniferous Forest ◽  
Late Glacial ◽  
Glacial Lake ◽  
Middle Pleistocene ◽  
Temperate Deciduous Forest ◽  
Late Glacial Period ◽  
Long Period ◽  
Temperate Deciduous

The Older Drift of north Birmingham infills a system of pre-glacial valleys. Its stratigraphy has been worked out, chiefly from borehole records, showing it to comprise the deposits of two separate glaciations—the Lower and Upper Glacial Series, and an intervening Interglacial Series. It records the deposition during the Lower Glacial Series of fluvioglacial sediments followed by those of a glacial lake during the late-glacial period. A small remnant of the latter persisted into the Interglacial as a lake at Nechells and was gradually infilled with lake muds. After a temporary period of low water the level subsequently fell again, largely draining the lake which became covered with fen-wood and marsh receiving some fluviatile sediment. Other thin interglacial beds exist at Cardigan Street and possibly Washwood Heath. Elsewhere the period is represented by an unconformity. The Upper Glacial Series records the triple advance into the area of valley glaciers, accompanied by the formation of glacial lakes. In the intervening periods of retreat the valleys were receiving fluvioglacial sediment, and in one period were occupied by a second large glacial lake. A fourth advance of an ice sheet covered the area and completed the infilling of the valleys. A detailed study of the pollen and macrofossils from the Interglacial Series has enabled the reconstruction of the plant communities in the vegetation, and their succession throughout the Interglacial. This records a combination of changes due to the serai, edaphic and climatic development. Following an amelioration of climate temperate deciduous forest developed from open ‘sub-arctic’ scrub and grass/herb communities, with Alnus and Taxus later becoming locally important when the climate perhaps became wetter. Deterioration of soils during the long period of mild humid conditions led to the subsequent spread of heath and coniferous forest, which perhaps, as Abies forest, occupied the area during the period of optimum temperatures (summer). Later deterioration of the climate resulted in Pinus forests and heaths, the vegetation becoming increasingly open as the next glaciation approached. The Interglacial Series are correlated with Holsteinian interglacial sites elsewhere in Britain and on the Continent. This dates the Lower and Upper Glacial Series to the Elster and Saale Glaciations respectively, confirming their correlation with neighbouring areas.

scholarly journals Response of littoral chironomid communities and organic matter to late glacial lake—level, vegetation and climate changes at Lago dell’Accesa (Tuscany, Italy)

2007 ◽  
Vol 38 (4) ◽  
pp. 525-539 ◽  
Author(s):  
Laurent Millet ◽  
Boris Vannière ◽  
Valérie Verneaux ◽  
Michel Magny ◽  
Jean Robert Disnar ◽  
...  
Keyword(s):  
Organic Matter ◽  
Lake Level ◽  
Climate Changes ◽  
Late Glacial ◽  
Glacial Lake ◽  
Vegetation And Climate

Evidence of late glacial paleoseismicity from submarine landslide deposits within Lac Dasserat, northwestern Quebec, Canada

2016 ◽  
Vol 86 (2) ◽  
pp. 184-199 ◽  
Author(s):  
Gregory R. Brooks
Keyword(s):  
Ice Sheet ◽  
Late Glacial ◽  
Relative Strength ◽  
Submarine Landslide ◽  
Laurentide Ice Sheet ◽  
Glacial Lake ◽  
Event Horizons ◽  
Lake Ojibway

AbstractAn integrated seismo- and chronostratigraphic investigation at Lac Dasserat, northwestern Quebec, identified 74 separate failures within eight event horizons. Horizons E and B, and H and G have strong or moderately-strong multi-landslide signatures, respectively, composed of 11-23 failures, while horizons F, D, C, and A have minor landslide signatures consisting of a single or pair of deposit(s). Cores collected at six sites recovered glacial Lake Ojibway varve deposits that are interbedded with the event horizons. The correlation of the varves to the regional Timiskaming varve series allowed varve ages or ranges of varve ages to be determined for the event horizons. Horizons H, G, E, and B are interpreted to be evidence of paleoearthquakes with differing levels of interpretative confidence, based on the relative strength of the multi-landslide signatures, the correlation to other disturbed deposits of similar age in the region, and the lack or possibility of alternative aseismic mechanisms. The four interpreted paleoearthquakes occurred between 9770 ± 200 and 8470 ± 200 cal yr BP, when glacial Lake Ojibway was impounded behind the Laurentide Ice Sheet during deglaciation. They probably represent an elevated period of seismicity at deglaciation that was driven by crustal unloading.

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