Late-Glacial History of Lago Argentino, Argentina, and Age of the Puerto Bandera Moraines

2000 ◽  
Vol 54 (3) ◽  
pp. 339-347 ◽  
Author(s):  
Jorge A. Strelin ◽  
Eduardo C. Malagnino
Keyword(s):  
Radiocarbon Dating ◽  
Younger Dryas ◽  
Late Glacial ◽  
The West ◽  
Middle Holocene ◽  
Last Glaciation ◽  
Western Area ◽  
History Of ◽  
A Minor ◽  
Northern Branch

In the west-central part of Lago Argentino, the Puerto Bandera moraines are clearly detached from longer, more prominent moraines of the last glaciation and from shorter and smaller Neoglacial moraines. Scientists have long speculated about the age of the Puerto Bandera moraines. Detailed geomorphologic studies in the western area of Lago Argentino, including stratigraphic profiles at Bahı́a del Quemado in the northern branch (Brazo Norte), indicate that the Puerto Bandera moraines were deposited by three pulses of ice. Each of the three pulses is represented by single moraine ridges and belts of tightly arranged ridges. The timing of the three glacier advances was established by radiocarbon dating, including data published by John Mercer. The oldest moraine system, formed during the Puerto Bandera I substade, was deposited ca. 13,000 14C yr B.P. Moraines of the Puerto Bandera II substade were deposited ca. 11,000 14C yr B.P. The youngest moraine system was deposited during a minor readvance, shortly before 10,390 C14 yr B.P., and thus appears to have occurred some time during the European Younger Dryas interval. After this third substade, the ice tongues retreated into the interior branches of Lago Argentino and have remained there since. Evidence found at Bahı́a del Quemado, together with data provided by other authors, attests to a significant climatic change by the middle Holocene, which we believe occurred during the Herminita advance, the first Holocene glacial readvance recognized within the area.

scholarly journals Some aspects of the last glaciation in the Mazury Lake District (north-eastern Poland)

2013 ◽  
Vol 53 (1) ◽  
pp. 3-8 ◽  
Author(s):  
Katarzyna Pochocka-Szwarc
Keyword(s):  
Ice Sheet ◽  
Late Glacial ◽  
Climatic Changes ◽  
Lake District ◽  
Last Glaciation ◽  
North Eastern ◽  
Melt Water ◽  
History Of ◽  
Organic Sediments ◽  
Late Glacial And Holocene

ABSTRACT The morphology of the Mazury Lake District (north-eastern Poland) dates from 24-19 ka (main stadial of the youngest Vistulian glaciation). During this last glacial maximum (MIS 2) a belt with lacustrine basins was formed when the ice sheet retreated at the end of the Pomeranian phase. The ice-sheet retreat is morphologically also expressed by the occurrence of end moraines. The study area is situated in the Skaliska Basin, in the northern part of the Lake District (near the Polish/ Russian border), at the periphery of zone with end moraines. Originally the basin was an ice-dammed depression filled with melt water; the water flowed out into the developing Pregoła valley when the ice retreated and did no longer dam off the depression. The basin, which is surrounded by hill-shaped moraines, is filled now with Late Glacial and Holocene glaciolacustrine sediments. The organic sediments of the basin record the history of the Late Glacial and Holocene climatic changes in this region.

A late-glacial – Holocene palaeoecological record from Pye Lake on the eastern shore of Nova Scotia, CanadaGeological Survey of Canada Contribution 20080395.

2009 ◽  
Vol 46 (9) ◽  
pp. 637-650 ◽  
Author(s):  
Robert J. Mott ◽  
Ian R. Walker ◽  
Samantha L. Palmer ◽  
Martin Lavoie
Keyword(s):  
Nova Scotia ◽  
Younger Dryas ◽  
Late Glacial ◽  
Forest Composition ◽  
Eastern Shore ◽  
The North ◽  
Tundra Vegetation ◽  
History Of ◽  
Climatic History ◽  
Recent Sediments

Pollen and chironomid analyses and radiocarbon dating at Pye Lake on the eastern shore of Nova Scotia are used to outline the vegetation and climatic history of the area. The coast was deglaciated prior to ∼12 200 14C BP (14 300 cal BP), and herbaceous tundra vegetation invaded the area. Midge-inferred maximum summer surface-water temperatures in the lake ranged between 9 and 11 °C. Subsequent gradual warming to ∼18 °C by 10 800 14C BP (12 725 cal BP) favoured the migration of a variety of herbaceous and shrub taxa into the region. Rapid cooling to ∼10 °C saw vegetation revert to herbaceous tundra communities. This interval, related to the Younger Dryas cold interval of the North Atlantic and Europe, lasted until ∼10 000 14C BP (11 630 cal BP). The climate then warmed again to conditions similar to those that prevailed immediately before onset of Younger Dryas cooling. Further warming saw successive tree species migrate into the area until, by the mid-Holocene, the forests contained most of the taxa prevalent today. Since ∼3500 years ago, cooling of the climate has favoured conifer species over broad-leaved taxa. Agriculture and logging practices in the last 150 years have altered the forest composition, but pollen analysis of the most recent sediments cannot resolve these changes adequately.

scholarly journals Reconstruction of vegetation in the foothills of the Carpathian Mountains, Gorgany region, in the late glacial (based on pollen data of peat-bog Pidluzhia)

2015 ◽  
pp. 333-340
Author(s):  
Natalia Chumak
Keyword(s):  
Key Words ◽  
Radiocarbon Dating ◽  
Environmental Changes ◽  
Younger Dryas ◽  
Late Glacial ◽  
Peat Bog ◽  
Pollen Data ◽  
Carpathian Mountains ◽  
The Holocene ◽  
Short Period

The environmental changes on short-period stages of the Late Glacial were reconstructed based on pollen data of peat-bog Pidluzhia deposits and their radiocarbon dating. There are the Older and Younger Dryas, the Allerod (three phases) are allocated on palynological data in the Late Glacial. Vegetation had evolved from cold meadows to pine forest during this time. The transition from the Late Glacial to the Holocene was identified by the emergence of broad-leaved trees (elm, oak and linden), the spreading of spruce and disappearance of xerophytic elements. Key words: paleovegetation, paleoclimate, palinology, the Late Glacial, the foothills of the Carpathian Mountains.

scholarly journals Palynology and Archaeology of Late Vistulian and Early Holocene Sites in Lubuskie Lake District, Western Poland

2014 ◽  
Vol 31 (1) ◽  
pp. 39-50 ◽  
Author(s):  
Iwona Okuniewska-Nowaczyk ◽  
Iwona Sobkowiak-Tabaka
Keyword(s):  
Small Area ◽  
Younger Dryas ◽  
Late Glacial ◽  
Early Holocene ◽  
Lake District ◽  
Multidisciplinary Research ◽  
Late Vistulian ◽  
Palynological Spectrum ◽  
History Of ◽  
Palynological Records

Abstract The Lubuskie Lake District played an important part in recolonisation of the Polish Plain due to its location and the character of the terrain. Despite that, it is and especially its northern part, poorly explored regarding both history of Late Glacial and early Holocene settlements, and the natural environment. The paper presents results of multidisciplinary research in this area. The most spectacular discoveries were connected with remains of settlements of the Hamburgian culture societies at Myszęcin - currently the richest site of this culture over the entire North European Plain. In the vicinity of this site several Late Palaeolithic and Mesolithic settlements of varied functions were recorded. First palynological records came from the Younger Dryas sediments in this area. In a log with a palynological spectrum comprising Younger Dryas and the beginning of the Holocene, a charcoal dust was found and it could indicate human activity as humans lived at a lake shore. An important complement to the image of the Late Glacial settlement at the Lubuskie Lake District was provided by the research near Lubrza that resulted in data regarding settlements of the Federmesser and Świderian culture societies. This region was not typical in a palynological spectrum of deposits during Allerød but also indicated highly diversified thickness of basal peat in a small area.

scholarly journals Geochronology of the Holocene of the Belorussian Polessie

Radiocarbon ◽  
1993 ◽  
Vol 35 (3) ◽  
pp. 435-439 ◽  
Author(s):  
A. V. Matveev ◽  
E. A. Krutous ◽  
V. P. Zernitskaya
Keyword(s):  
Radiocarbon Dating ◽  
Younger Dryas ◽  
The Holocene ◽  
Last Glaciation

We distinguished major stages of the last glaciation (Bølling, Older Dryas, Allerød, Younger Dryas) and the Holocene by radiocarbon dating and paleobotanical analyses. Our paleobotanical investigation of peatlands is well correlated with independent 14C data. We establish that the Atlantic and Subboreal stages of the Holocene have three divisions, and that the Subatlantic has two.

Younger Dryas to mid-Holocene environmental history of the lowlands of NW Transylvania, Romania

2007 ◽  
Vol 68 (3) ◽  
pp. 364-378 ◽  
Author(s):  
Angelica Feurdean ◽  
Volker Mosbrugger ◽  
Bogdan P. Onac ◽  
Victor Polyak ◽  
Daniel Veres
Keyword(s):  
Environmental History ◽  
Environmental Changes ◽  
Younger Dryas ◽  
Total Carbon ◽  
Small Populations ◽  
Minor Constituent ◽  
Effective Moisture ◽  
Competition Effects ◽  
History Of ◽  
A Minor

AbstractPollen, micro-charcoal and total carbon analyses on sediments from the Turbuta palaeolake, in the Transylvanian Basin of NW Romania, reveal Younger Dryas to mid-Holocene environmental changes. The chronostratigraphy relies on AMS 14C measurements on organic matter and U/Th TIMS datings of snail shells. Results indicate the presence of Pinus and Betula open woodlands with small populations of Picea, Ulmus, Alnus and Salix before 12,000 cal yr BP. A fairly abrupt replacement of Pinus and Betula by Ulmus-dominated woodlands at ca. 11,900 cal. yr BP likely represents competition effects of vegetation driven by climate warming at the onset of the Holocene. By 11,000 cal yr BP, the woodlands were increasingly diverse and dense with the expansion of Quercus, Fraxinus and Tilia, the establishment of Corylus and the decline of upland herbaceous and shrubs taxa. The marked expansion of Quercus accompanied by Tilia between 10,500 and 8000 cal yr BP could be the result of low effective moisture associated with both low elevation of the site and with regional change towards a drier climate. At 10,000 cal yr BP, Corylus spread across the region, and by 8000 cal yr BP it replaced Quercus as a dominant forest constituent, with only little representation of Picea abies. Carpinus became established around 5500 cal yr BP, but it was only a minor constituent in local woodlands until ca. 5000 cal yr BP. Results from this study also indicate that the woodlands in the lowlands of Turbuta were never closed.

scholarly journals Interdisciplinary studies of spring mire deposits from Radzików (South Podlasie Lowland, East Poland) and their significance for palaeoenvironmental reconstructions

2012 ◽  
Vol 39 (1) ◽  
pp. 10-29 ◽  
Author(s):  
Radosław Dobrowolski ◽  
Irena Pidek ◽  
Witold Alexandrowicz ◽  
Stanisław Hałas ◽  
Anna Pazdur ◽  
...  
Keyword(s):  
Radiocarbon Dating ◽  
Environmental Changes ◽  
Younger Dryas ◽  
Late Glacial ◽  
Plant Macrofossils ◽  
Interdisciplinary Studies ◽  
Carbon Stable Isotopes ◽  
Calcareous Tufa ◽  
Palaeoenvironmental Reconstructions ◽  
Late Glacial And Holocene

Abstract The paper presents the results of interdisciplinary (multiproxy) palaeoenvironmental studies of peat — calcareous tufa depositional sequences of spring mire from Radzików site (east Poland). Analyses of three biotic proxies (plant macrofossils, pollen, molluscs) were supplemented with sedimentological, geochemical, oxygen and carbon stable isotopes analyses and radiocarbon dating and used for reconstruction of environmental changes in Late Glacial and Holocene. The obtained results enable us to (1) reconstruct main phases of mire development and (2) determine environmental factors influencing changes of water supply. The object started to develop in Allerød. The Late Glacial and Early Holocene deposit sequence is relatively thick (about 1.0 m), with good palaeoecological record. The boundary between Younger Dryas and Preboreal is especially well confirmed by palynological and malacological analyses as well as radiocarbon dating. The Mesoholocene deposits are considerably worse preserved. Mire development was evaluated in terms of general mire ecology.

Zîn-ə Hördemîr: A Lekî Satirical Verse from Lekistan

2008 ◽  
Vol 18 (3) ◽  
pp. 295-309
Author(s):  
MUSTAFA DEHQAN
Keyword(s):  
Geographical Area ◽  
Intellectual Life ◽  
Oral Literature ◽  
The West ◽  
New Era ◽  
History Of ◽  
The Subject ◽  
A Minor ◽  
North Western ◽  
Made In

With the exception of a minor mention, which Sharaf Khān (b.1543) made in theSharafnāma, the first information about the most southern group of Kurdish tribes in Iranian Kurdistan, the Lek, first became available to modern readers inBustān al-Sīyāḥa, a geographical and historical Persian text by Shīrwānī (1773–1832). These hitherto unknown Lek communities, were probably settled in north-western and northern Luristan, known as Lekistan, by order of Shāh ‘Abbās, who wished in this way to create some support for Ḥusayn Khān, thewālīof Luristan. Many of the centres of Lekî intellectual life in the late Afshārīd and early Zand period, which is also of much importance in that the Zand dynasty arose from it, are located in this geographical area. One has only to call to mind the names of such places as Alishtar (Silsila), Kūhdasht, Khāwa, Nūr Ābād, Uthmānwand and Jalālwand in the most southern districts of Kirmānshāh, and also the Lek tribes of eastern Īlām. The very mention of these cities and villages already sets in motion in one's imagination the parade of Twelver Shiites, Ahl-i Haqq heretics, and non-religious oral literary councils which constitutes the history of Lekî new era. But unfortunately little of this is known in the West and Lekî literature remains one of the neglected subjects of literary and linguistic Kurdish studies. This important oral literature and also some written manuscripts are unpublished and untranslated into western languages. The subject of this article is the translation ofZîn-ə Hördemîr, as an example of a genre of Lekî written literature which also provides linguistic data for the Lekî dialect of southern Kurdish.

Chironomid Evidence for Late-Glacial Climatic Reversals in Maine

1995 ◽  
Vol 43 (3) ◽  
pp. 405-413 ◽  
Author(s):  
Les C. Cwynar ◽  
André J. Levesque
Keyword(s):  
Surface Water ◽  
Younger Dryas ◽  
Late Glacial ◽  
Strongly Correlated ◽  
Maritime Canada ◽  
A Minor

AbstractPreviously published pollen studies from Maine have not identified any late-glacial reversals despite evidence for them from adjacent areas. The distribution and abundance of midge flies are strongly correlated with summer surface-water temperatures. We analyzed fossils of larval midge flies from the sediments of two ponds (Trout and Tilley) from Maine. Each site reveals a major and a minor oscillation during which inferred summer surface-water temperatures fell by 7-13°C and 2.1-2.6°C, respectively. We tentatively correlate these events with the Younger Dryas cooling and Killarney Oscillation reported from adjacent Maritime Canada, where they have been AMS 14C-dated at 10,770-10,000 and 11,160-10,910 yr B.P., respectively. A third oscillation occurs at the northernmost site, Tilley Pond, and may represent the effects of a local ice advance in northern Maine.

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