scholarly journals Late Quaternary Deglaciation, Glaciomarine Sedimentation and Glacioisostatic Recovery in the Rivière Nastapoka Area, Eastern Hudson Bay, Northern Québec

2005 ◽  
Vol 57 (1) ◽  
pp. 65-83 ◽  
Author(s):  
Patrick Lajeunesse ◽  
Michel Allard
Keyword(s):  
Sea Level ◽  
Late Quaternary ◽  
Phase 1 ◽  
Second Phase ◽  
Hudson Bay ◽  
Silty Clay ◽  
Paleoenvironmental Reconstruction ◽  
Relative Sea Level ◽  
Radiocarbon Dates ◽  
Fluvial Terraces

Abstract This study presents a paleoenvironmental reconstruction of deglaciation dynamics and chronology, glaciomarine and postglacial sedimentation, as well as glacioisostatic recovery in the Rivière Nastapoka area, eastern Hudson Bay. Results indicate that the retreat of Québec-Labrador ice was mainly controlled by topography and was marked by four phases. Radiocarbon dates indicate that deglaciation began about 8.3 ka cal. BP and was characterized by a stillstand of the ice margin in the Nastapoka Hills that lead to the deposition of a drift belt in a high relative sea-level (Phase 1). After this stabilisation, the ice margin retreated rapidly eastward in a region of low relief and deposited a drape of silty clay in a falling relative sea-level (Phase 2). A second phase of stabilization of the ice margin lasted until at least 7.2 ka cal.BP on the higher shield peneplaine east of the limit of the Tyrrell Sea (Phase 3). This lead to the deposition of a belt of glaciofluvial deltas in a lower relative sea-level. Following this stillstand, the eastward retreat and subsequent ablation of the ice in central Québec-Labrador generated meltwater that transported large volumes of glacial sediments by fluvial processes and downcutting of fluvial terraces in previously deposited glaciofluvial and marine sediments (Phase 4). Glacioisostatic rebound reached 0.07 m/yr during the early phase of deglaciation and decreased to 0.04 m/yr between 6 and 5 ka cal. BP and 0.016 m/yr in the last 1000 years.

Palaeoenvironmental reconstruction of late Quaternary foraminifera and molluscs from the ENEA borehole (Versilian plain, Tuscany, Italy)

2010 ◽  
Vol 74 (2) ◽  
pp. 265-276 ◽  
Author(s):  
M. Gabriella Carboni ◽  
Luisa Bergamin ◽  
Letizia Di Bella ◽  
Daniela Esu ◽  
Emanuela Pisegna Cerone ◽  
...  
Keyword(s):  
Sea Level ◽  
Late Quaternary ◽  
Central Italy ◽  
Vertical Displacement ◽  
Second Phase ◽  
Sea Level Changes ◽  
Radiocarbon Dates ◽  
Radiocarbon Data ◽  
Palaeoecological Reconstruction ◽  
Lagoon Environment

AbstractForaminifera and molluscs from the 90 m deep ENEA borehole (Versilian plain, central Italy) were studied for paleoenvironmental purposes. Palaeontological analyses, integrated with U/Th and radiocarbon data, helped to recognize late Quaternary sea-level changes and supplied results on tectonic mobility of the area. The study highlighted four sedimentary phases. The first phase consists of a shore environment attributed to MIS 7.1. A hiatus corresponding to MIS 6 is hypothesized at the top of this interval. Recognition of the paleo-shoreline of MIS 7.1 at − 72.8 m signifies a vertical displacement due to the extensional tectonics of the Apennine orogenesis. The second phase consists of a transgressive succession with evidence of warm temperatures, which was interpreted as part of the transgression leading to the MIS 5.5 highstand. The third phase includes sub-aerial and lacustrine deposits. Radiocarbon dates and palaeoecological reconstruction led us to attribute this interval to MIS 4, MIS 3 and MIS 2. The fourth phase begins with a lagoon environment attributable to Holocene sea-level rise and ends with marsh episodes, signifying the progradation of the alluvial plain. This reconstruction confirms the hypothesis of tectonic stability for the Versilian area during the Holocene.

SEA-LEVELS, LATE QUATERNARY | Late Quaternary Relative Sea-Level Changes at Mid-Latitudes

2013 ◽  
pp. 489-494 ◽  
Author(s):  
A.C. Kemp ◽  
B.P. Horton ◽  
S.E. Engelhart
Keyword(s):  
Sea Level ◽  
Late Quaternary ◽  
Sea Level Changes ◽  
Relative Sea Level ◽  
Sea Levels

Late Quaternary relative sea-level changes and vertical movements at Lipari (Aeolian Islands)

2002 ◽  
Vol 17 (5-6) ◽  
pp. 459-467 ◽  
Author(s):  
N. Calanchi ◽  
F. Lucchi ◽  
P. A. Pirazzoli ◽  
C. Romagnoli ◽  
C. A. Tranne ◽  
...  
Keyword(s):  
Sea Level ◽  
Late Quaternary ◽  
Sea Level Changes ◽  
Relative Sea Level ◽  
Vertical Movements ◽  
Aeolian Islands

Constraints on mantle viscosity from relative sea level variations in Hudson Bay

1992 ◽  
Vol 19 (12) ◽  
pp. 1185-1188 ◽  
Author(s):  
J. X. Mitrovica ◽  
W. R. Peltier
Keyword(s):  
Sea Level ◽  
Hudson Bay ◽  
Relative Sea Level ◽  
Mantle Viscosity ◽  
Sea Level Variations

scholarly journals Relative sea-level changes in crete: reassessment of radiocarbon dates from Sphakia and west Crete

2002 ◽  
Vol 97 ◽  
pp. 171-200 ◽  
Author(s):  
Simon Price ◽  
Tom Higham ◽  
Lucia Nixon ◽  
Jennifer Moody
Keyword(s):  
Sea Level ◽  
Late Antiquity ◽  
Isotopic Fractionation ◽  
Sea Level Changes ◽  
Relative Sea Level ◽  
Radiocarbon Dates ◽  
Sea Levels ◽  
Catastrophic Earthquake ◽  
Radiocarbon Data ◽  
Calendar Dates

This article is concerned with the recognition and dating of Holocene relative sea-level changes along the coast of west Crete (an island located in the active Hellenic subduction arc of the southern Aegean) and in particular in Sphakia. Radiocarbon data for changes in sea levels collected and analysed previously must (a) be recorrected to take into account isotopic fractionation, and (b) recalibrated by using the new marine reservoir value. These new radiocarbon dates are analysed using Bayesian statistics. The resulting calendar dates for changes in sea level are younger than previously assumed. In particular the Great Uplift in western Crete in late antiquity must be dated to the fifth or sixth century AD, not to AD 365. Moreover, recent work on tectonics suggests that the Great Uplift need not have been accompanied by a catastrophic earthquake. Finally, we consider the consequences of the Great Uplift for some coastal sites in Sphakia.

A reconnaissance survey of late Quaternary sea levels, Bella Bella/Bella Coola region, central British Columbia coast

1978 ◽  
Vol 15 (3) ◽  
pp. 341-350 ◽  
Author(s):  
J. T. Andrews ◽  
R. M. Retherford
Keyword(s):  
British Columbia ◽  
Sea Level ◽  
Late Quaternary ◽  
Middle Part ◽  
Relative Sea Level ◽  
Marine Transgression ◽  
Sea Levels ◽  
Reconnaissance Survey ◽  
Rate Of Emergence ◽  
Bella Coola

A preliminary relative sea level curve that covers the last 10 200 years is derived for the area of the islands and outer mainland centered on Bella Bella and Namu, the central coast of British Columbia. The curve shows postglacial emergence of 17 m over this period. The rate of emergence was ~0.6 m/100 year about 9000 BP, and present sea level was attained between 7000 and 8000 BP. Relative sea level continued to fall until the last few hundred to one thousand years BP when a marine transgression led to a rise of sea level and resultant erosion of many coastal Indian middens. Marine limits on the outer islands may reach 120 m asl, whereas in the middle part of the fiord country observed delta surfaces are lower (54–75 m asl). Elevations of raised deltas then attain ~150 m at fiord heads. A readvance of the ice front ≤ 12 210 ± 330 BP (GSC-1351) is suggested by the stratigraphy of one section.

A relative sea-level history for Arviat, Nunavut, and implications for Laurentide Ice Sheet thickness west of Hudson Bay

2014 ◽  
Vol 82 (1) ◽  
pp. 185-197 ◽  
Author(s):  
Karen M. Simon ◽  
Thomas S. James ◽  
Donald L. Forbes ◽  
Alice M. Telka ◽  
Arthur S. Dyke ◽  
...  
Keyword(s):  
Sea Level ◽  
Late Holocene ◽  
Ice Sheet ◽  
Tidal Range ◽  
Laurentide Ice Sheet ◽  
Hudson Bay ◽  
Level Curve ◽  
Relative Sea Level ◽  
Vertical Land Motion ◽  
Crustal Uplift

AbstractThirty-six new and previously published radiocarbon dates constrain the relative sea-level history of Arviat on the west coast of Hudson Bay. As a result of glacial isostatic adjustment (GIA) following deglaciation, sea level fell rapidly from a high-stand of nearly 170 m elevation just after 8000 cal yr BP to 60 m elevation by the mid Holocene (~ 5200 cal yr BP). The rate of sea-level fall decreased in the mid and late Holocene, with sea level falling 30 m since 3000 cal yr BP. Several late Holocene sea-level measurements are interpreted to originate from the upper end of the tidal range and place tight constraints on sea level. A preliminary measurement of present-day vertical land motion obtained by repeat Global Positioning System (GPS) occupations indicates ongoing crustal uplift at Arviat of 9.3 ± 1.5 mm/yr, in close agreement with the crustal uplift rate inferred from the inferred sea-level curve. Predictions of numerical GIA models indicate that the new sea-level curve is best fit by a Laurentide Ice Sheet reconstruction with a last glacial maximum peak thickness of ~ 3.4 km. This is a 30–35% thickness reduction of the ICE-5G ice-sheet history west of Hudson Bay.

Postglacial relative sea-level change, Port au Port area, west Newfoundland

1985 ◽  
Vol 22 (7) ◽  
pp. 1039-1047 ◽  
Author(s):  
I. A. Brookes ◽  
D. B. Scott ◽  
J. H. McAndrews
Keyword(s):  
Sea Level ◽  
Late Holocene ◽  
High Water ◽  
Relative Sea Level ◽  
Radiocarbon Dates ◽  
Ice Load ◽  
Bay Area ◽  
Port Area ◽  
Minimum Age ◽  
Late Wisconsinan

We first report pollen and foraminifera analyses and radiocarbon dates from two cores taken from salt-marsh deposits bordering Port au Port Bay, southwestern Newfoundland. Results show that relative sea level (RSL) stood at 2.8 m below present higher high-water level (HHWL) at 2770 ± 300 years BP and at −1.8 m at 2365 ± 175 years BP at the core sites. They permit calculation of a rate of late Holocene RSL change from western Newfoundland. We then report other available dates bearing on the earlier RSL record of this area.A date of 5800 ± 200 years BP fixes the age of minimum RSL in Port au Port Bay at 11–14 m below present. A date of 9350 ± 120 years BP from St. George's provides a minimum age for the passage of sea level below present there. A date of 12 600 ± 140 years BP from Stephenville fixes a sea level at 29 m above present, whereas one of 13 600 ± 110 years BP from Abrahams Cove dates the marine limit at 44 m. These geographically restricted data closely constrain a curve of postglacial RSL change in the Port au Port Bay – northern St. George's Bay area. The form of the curve supports a recent model predicting sea-level response to wastage of a limited late Wisconsinan ice load in the wider region.

The late Quaternary history of Greely Fiord and its tributaries, west-central Ellesmere Island

1990 ◽  
Vol 27 (2) ◽  
pp. 255-270 ◽  
Author(s):  
John England
Keyword(s):  
Sea Level ◽  
Late Quaternary ◽  
Sensu Stricto ◽  
Ellesmere Island ◽  
Relative Sea Level ◽  
Ice Caps ◽  
Last Glaciation ◽  
West Central ◽  
Grounding Line ◽  
Minimum Age

Moraines and meltwater channels mark the limit of the last glaciation that interfingered with the sea around the perimeter of Greely Fiord and its tributaries. The extent of this ice advance was dictated predominantly by its proximity to the sea. Consequently, the large tidewater glaciers at the fiord heads today were so constrained by calving that they advanced only 5–10 km. Similarly, grounding-line deposits from widespread plateau ice caps also terminate just below marine limit. The most extensive outlet glaciers, which advanced 20–35 km beyond present margins, are simply those that had access to the most extensive terrain above marine limit, i.e., the northwest margin of the Agassiz Ice Cap.Forty-one new 14C dates are presented. The onset of the last ice advance must predate marine shells collected from sediments overlying a former grounding line when sea level was 122 m higher than present. At this site, the lowermost shells collected from glaciomarine silts dated 38 070 ± 410 BP, whereas a surface sample 13 m above them dated 22 900 ± 190 BP. Although both dates may be minimum estimates, they are nonetheless associated with an ice margin that retreated only a few kilometres by 7850 BP, suggesting the maintenance of the glacioisostatic loading (and relative sea level) during the interim. Nearby, shells in growth position overlying bedrock confirm that relative sea level was > 83 m asl by 38 010 ± 410 BP (minimum age). These marine deposits lie outside the last ice limit and are not overlain by glacigenic sediments.Distal to the last ice limit, Greely Fiord was occupied by the full glacial sea, whose limit is marked by discontinuous beaches and wave-cut benches. The full glacial sea rises from 116 m north of Greely Fiord to a maximum elevation of 148 m bordering its south shore from which it descends to 112 m asl near the head of Cañon Fiord. Numerous 14C dates on shells collected within 8 m of marine limit show that the full glacial sea remained stable from at least 8400 to 7400 BP. Several other shell samples collected ~20 m below marine limit are much older (> 22 000 BP). The position of relative sea level between ca. 8000 and > 22 000 BP is uncertain; however, stratigraphic evidence for an intervening regression has not been found.The modest extent of the last ice limit encircling Greely Fiord, together with its occupancy by the full glacial sea, is fully compatible with the paleogeography previously reported from northeast Ellesmere Island and northwest Greenland. Furthermore, this data base provides a reinterpretation of a 500 km transect previously reported along west-central Ellesmere Island to the south and affirms that the Innuitian Ice Sheet, defined sensu stricto for the last glaciation, is supplanted by the full glacial Innuitian Sea, which penetrated the Queen Elizabeth Islands, constraining the last ice limit.

Lithological control of drainage basins development post LGM and oscillating climate condition

2020 ◽  
Author(s):  
Shyh-Jeng Chyi ◽  
Jia-Hong Chen ◽  
Jiun-Yee Yen ◽  
Lih-Der Ho ◽  
Chia-Hung Jen ◽  
...  
Keyword(s):  
Sea Level ◽  
Igneous Rock ◽  
Large Scale ◽  
River Mouth ◽  
River Basins ◽  
Relative Sea Level ◽  
Radiocarbon Dates ◽  
The Pacific ◽  
Geomorphic Features ◽  
Mountain Front

<p>Compare to rivers originated from western Taiwan flowing westward, rivers   originated from the southeastern side of the Central Range and the eastern side of the Coastal Range flow eastward directly into the Pacific Ocean and form very narrow alluvial plains or coastal plains immediately next to the mountain front. Based on the field evidences and mapping from field and high-res DTM, we classified these river basins into two types.</p><p> </p><p>The geomorphic features of the first type are remarkably wide valley plain with flights of fill terrace and relatively narrow active channel in the downstream area. The radiocarbon dates of terrace sediments indicate that large-scale aggradation took place before 7ka, and formed fill terraces with the largest relative height of around 50 meters relative to the modern channel bed in the mid to late Holocene. We proposed the landscape evolutionary history for the first type of river basins is that significant river aggradation caused by rapid sea-level rise in estuary during the late Pleistocene to the early Holocene, followed by continuous and slow uplift or the relative sea-level falling that induced a long term basin-wide river incision.</p><p> </p><p>The geomorphic features of the second type of the river basins are those that the knickpoint developed in the igneous rock gorge near the river mouth and often formed incised meander and unpaired rock terraces in its upstream area. The radiocarbon dates of terrace sediments indicate the average bedrock incision rate of upstream area is  noticeably lower than the rate near  the coast/river mouth area. For the second type river basins, we proposed that the climate turns warm and wet since the end of the last glacial period and the retreat of knickpoint in the igneous rock gorge exert the primary influence on terrace formation in the upper reaches, and the relative sea level falling is the main control on the terrace formation in the coastal area. In addition to those, the terraces of the main tributaries of the second type river basins which reveal the different cut-and-fill histories might be the results of complex response of sub-drainage systems to the multiple controls.</p>

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