Late Glacial

Keywords: triple oxygen isotopes gypsum hydration water relative humidity lake sediments Younger Dryas Late Glacial–Holocene transition Atmospheric relative humidity is an important parameter affecting vegetation yet paleo-humidity proxies are scarce and difficult to calibrate. Here we use triple oxygen (δ 17 O and δ 18 O) and hydrogen (δD) isotopes of structurally-bound gypsum hydration water (GHW) extracted from lacustrine gypsum to quantify past changes in atmospheric relative humidity. An evaporation isotope-mass-balance model is used together with Monte Carlo simulations to determine the range of climatological conditions that simultaneously satisfy the stable isotope results of GHW, and with statistically robust estimates of uncertainty. We apply this method to reconstruct the isotopic composition of paleo-waters of Lake Estanya (NE Spain) and changes in normalized atmospheric relative humidity (RH n) over the last glacial termination and Holocene (from ∼15 to 0.6 cal. kyrs BP...

Given the difficulty of separating the three Picea species—P. glauca, P. mariana, and P. rubens (white, black, and red spruce)—in the pollen record, little is known about their unique histories in eastern North America following deglaciation. Here we report the first use of a classification tree analysis (CART) to distinguish pollen grains of these species. It was successfully applied to fossil pollen from eight sites in Maine and one in Massachusetts. We focused on the late glacial/early Holocene (14,000 to 8000 cal yr B.P.) and the late Holocene (1400 cal yr B.P. to present)—the two key periods since deglaciation when Picea has been abundant in the region. The result shows a shift from a Picea forest of P. glauca and P. mariana in the late glacial to a forest of P. rubens and P. mariana in the late Holocene. The small number of P. rubens grains identified from the late glacial/early Holocene samples…

Changes in lake water temperature and trophic states were inferred using chironomid fossil assemblages from Lac Long Inférieur (Southern Alps, France). In the Late Glacial, a colder period, possibly analogous to the Younger Dryas, is characterised by a peak in Micropsectra, a cold stenothermic taxon. The increase in temperatures during the Late Glacial interstadial is indicated by a decrease in the percentages of cold stenothermic taxa (Tanytarsus lugens/Corynocera oliveri grp.) and by an increase in taxa linked to the development of vegetation in the littoral zone. The beginning of the Holocene is marked by the presence of taxa adapted to warmer and more eutrophic waters. During the Holocene, the progressive warming of the climate and increase in lake trophic status were indicated by the increase of eutrophic and warmer water indicators. An increase in tributary inflow into Lac Long Inférieur was also inferred by the increase in rheophilous taxa, reflecting increased snowmelt. During the Subatlantic, the composition of the chironomid spectra suggests a re-cooling of the climate and/or a decrease in lake trophic status.

A long pollen record is derived from sediments of a lake dammed behind a low moraine of the last glaciation at 3°S latitude in the Ecuadorian Andes and is compared with a glacial age pollen record from the Amazon rainforest immediately below. Lake Surucucho (Llaviucu) lies at ...

Michael Baales & Axel von Berg (1997): Tierfährten in der allerødzeitlichen Vulkanasche des Laacher See-Vulkans bei Mertloch, Kreis Mayen-Koblenz. Archäologisches Korrespondenzblatt 27, 1-12.

Bei archäologischen Ausgrabungen wurden 1993 zufällig Trittsiegel von Auerwild auf einer Aschenschicht des spätallerødzeitlichen Laacher See-Vulkans entdeckt. Weitere Ausgrabungen haben große Flächen mit diesen Trittsiegeln freigelegt, ebenso Fährten von vielen Pferden, Braunbären und Rotwild. Diese Befunde gewähren einen überraschenden Einblick in die background fauna der Federmesser-Gruppen am Mittelrhein.

During archaeological excavations in 1993, tracks of capercaillie were accidentally discovered on a layer of ash from the late Allerød Laacher See volcano. Further excavations have uncovered large areas with these footprints, as well as tracks of many horses, brown bears and red deer. These findings provide a surprising insight into the background fauna of the Central Rhineland Federmessergruppen.

After being completely depopulated during much of the Late Pleistocene, southern Scandinavia again became part of the human world around the middle of the 15th millennium before present (BP). The reindeer-hunters of the Hamburgian culture are associated with this first pioneer re-colonisation pulse, but there has been considerable debate about the particular kind of economic and mobility strategies practiced by these groups, and their cultural and biological relationship with the succeeding techno-complex in the region, the so-called Federmesser-Gruppen, remains controversial. This chapter presents a series of formal exploratory analyses addressing the culture-historical status of the pioneering techno-complexes in southern Scandinavia, their dating and possible mobility strategies. The results of these analyses suggest that the historically informative differences between the material culture of the Hamburgian and the Federmesser-Gruppen are so pronounced as to imply a significant culture-historical and/or demographic conjuncture, likely centred on the brief GI-d/Older Dryas cold/dry spell. Ethnographically derived demographic models are used to frame possible mechanisms for the demographic collapse of the initial pioneering groups at this time.

HEINSALU, ATKO, VESKI, SIIM and VASSILJEV, JÜRI 2000. Palaeoenvi- ronment and shoreline displacement on Suursaari Island, the Gulf of Finland. Bulletin of the Geological Society of Finland 72, Parts 1-2, 21-46. The island of Suursaari in the middle of the Gulf of Finland is exceptionally high (175 m a.s.l.). Sediment profiles from one mire and three lakes were in- vestigated

The palynological study of the lacustrine sediments from Lagaccione, a maar-lake near Lago di Bolsena in central Italy, has provided a palaeoenvironmental record for the last 100,000 years. The chronology of the sequence is based on sixteen radiocarbon dates and a tephra layer at the base of the St Germain II s.l. The pollen record, starting during the St Germain I forest phase and ending about 3000 years ago, shows that remarkable changes occurred in the floristic composition, in the structure of the vegetation and in the plant biomass, including also long-lasting periods of open woodlands, often with an appreciable floristic diversity, during the last pleniglacial. Three new vegetational oscillations (Etruria I, Etruria II and Etruria III), characterized by a well-defined vegetation composition and dynamics, have been recognized after the St Germain I forest phase and before the middle pleniglacial interstadials. New evidence has been obtained for a significant diffusion of deciduous trees in the Italian peninsula during the late-glacial.

A new pollen record from Lago di Vico (core V1) provides fundamental new information towards reconstruction of flora and vegetation history in central Italy during the last 90 000 years. The chronological framework is secured by seventeen AMS14C dates, one40Ar/39Ar date and tephra analyses. At the base of the pollen record, i.e. shortly after the40Ar/39Ar date 87 000±7000 B.P., three phases with significant expansion of trees are recorded in close succession. These forest phases, which stratigraphically correspond to St Germain II (and Ognon?) and precede pleniglacial steppe vegetation, are designated by the local names Etruria I, Etruria II and Etruria III. During the pleniglacial, a number of fluctuations of angiosperm mesophilous trees suggest the presence of tree refugia in the area. The lowest pollen concentration values are recorded at ca. 22 000 B.P. which corresponds with other pollen records from the region. The late-glacial is characterized by an expansion in the arboreal pollen curves that is less pronounced, however, than in other pollen profiles from Italy. The Holocene part of the profile is consistently dominated by deciduous oak pollen. No major changes in arboreal pollen composition are recorded but several marked and sudden declines of the tree pollen concentration suggest that the forest cover underwent dramatic changes. Clear evidence for human impact is recorded only when cultivated crops became important which dates to ca. 2630±95 B.P.

Michael Baales & Axel von Berg (1999): Völlig unerwartet: Tierfährten von Pferden, Braunbären, Rot- und Auerwild in Ablagerungen des allerfrdzeitlichen Laacher See-Vulkans (ca. 12.9 ky cal BP) bei Mertloch (Kr. Mayen-Koblenz, Neuwieder Becken, Rheinland-Pfalz, Deutschland). Tier und Museum 6, 68-74.

Pleistozäne Tierfährten sind eine relativ seltene Fundgattung. 1993, 1996 und 1997 konnten jedoch bei Mertloch im Südwesten des mittelrheinischen Neuwieder Beckens zahketche sehr gut erhaltene spätpleistozäne Tierfährten in einem speziellen geologischen Kontext dokumentiert werden. Die Fährten fanden sich auf einem Aschenhorizont des Laacher See-Vulkans, der von weiteren Ablagerungen dieser letzten Vulkaneruption am Mittelrhein bedeckt bzw. unterlagert wurde. Der Laacher See-Vulkan eruptierte in der zweiten Hälfte des Allerød-Interstadials vor etwa 12.900 Jahren (= 11,1 ka 14C BP) und verschüttete das gesamte Neuwieder Becken mit
mächtigen vulkanischen Sedimenten. Die in Mertloch dokumentierten Tierfährten lassen sich verschiedenen borealen Waldarten zuweisen; es dominieren Auerhühner (bei einem Auerhahn, Tetrao urogallus), gefolgt von einer Rothirschkuh mit ihrem Kalb (Cervus elaphus) und zwei Braunbären (Ursus arctos; eine Fährte konnte auf ca. 70 m verfolgt werden). Weiterhin waren zahlreiche Fährten von Pferden (Equus ferus) vorhanden. Diese Tierart war am Mittelrhein trotz der nachhaltig geänderten Umweltverhältnisse (von der trocken-kalten Lößsteppe zu den Waldbiotopen der Allerød-Zeit) noch reichlich vertreten.

The unexpected: fossil animal tracks of horses, brown bear, red deer, and capercailie interstratified in the Allerød interstadial Laacher See-Tephra (ca 12.9 ky cal BP) near Mertloch (distr. Mayen-Koblenz, Neuwied Basin, Rhineland-Palatinate, Germany).
Animal tracks are rarely known from the Pleistocene, but in 1993, 1996 and 1997 it was possible to find well preserved tracks of several Final Pleistocene animal species in a special geological context to the southwest of the Central Rhineland Neuwied Basin near Mertloch. The tracks were preserved in an ash horizon interstratified in further deposits of the Laacher See-volcano dated to around 12,9 ky cal BP (ca 11,1 kyr 14C BP) which covered the whole landscape of the Neuwied Basin during the second half of the Allerød interstadial. The animal tracks at Mertloch can be attributed
to several boreal species; there are mainly f'emale and one male capercailie (Tetrao urogallus), two brown bears (Ursas arctos) – one track was preserved up to 70 m –, one red deer hind (Cervus elaphus') with a calf, and several horses (Equus Jbrus) together with young foals, a species which survived into the boreal Allerød environment from the earlier Late Pleistocene steppic biotopes.

Planktonic foraminifera and coccoliths were analyzed from six gravity cores obtained on a deep terrace located on the upper continental slope of the Gulf of Cadiz, between 400 and 700 m water depth. The lithology of these cores consists mainly of muds with some interbedded sandy or silty foraminifer-rich layers that have been reported as contourites originated by the action

Martin Street & Michael Baales (1999): Pleistocene/Holocene changes in the Rhineland fauna in a northwest European context. In: Norbert Benecke (Hrsg.): The Holocene History of the European Vertebrate Fauna. Modern Aspects of Research. Workshop Berlin 1998. Archäologie in Eurasien. Rahden, 9-38.

Four phases in the devclopment ot the large and small vertebrate fauna of the Rhineland (terminal Pleniglacial, Allerød interstadial, Younger Dryas, middle Preboreal) are characterised by rich faunal assemblages from archaeological sites dated to between the last (Würm/Weichselian) Pleniglacial (ca. 23 ky cal BP) and the carly Holocene (ca. 10 ky cal BP). Data from the Rhineland are described and compared with those from neighbouring regions, panicularly with norhwestern Europe. The observed changes in thc faunal record reflect known climatic oscillations of the northern hemisphere.

Die Entwicklung der Groß- und Kleinsäugerfauna des Rheinlandes nach dem letzten Kältemaximum (ca. 23 ka cal BP) der letzten Eiszeit (Würrn/Weichsel) bis zum frühen Holozän (ca. 10 ka cal BP) ist vor allem für vier Phasen (ausgehendes Pleniglazial, Allerød-lnterstadial, Jüngere Dryaszeit und mittleres Präboreal) aufgrund der reichen Fauna archäologischer Fundplätze charakterisierbar. Die hier erkennbaren Veränderungen spiegeln die bekannten Klimaschwarkungen auf der nördlichen Erdhalbkugel wider. Vorgestellt werden eine Zusammenfassung, Charakterisicrung und Interpretation der vorhandenen Daten für das Rheinlard im Vergleich zu benachbarten Regionen, vor allem Nordwest-Europas.