Solr Search · GéoProdig, portail d'information géographique

Signification dynamique et climatique des formations et terrasses fluviatiles quaternaires dans les Alpes et leur périphérie. in Colloque AFEQ, Paris 1983. (Dynamic and climatic significance of Quaternary fluviatile deposits and terraces in the Alps

Two sediment cores from Kaiyak and Squirrel lakes in north western Alaska yielded pollen records that date to ca. 39,000 and 27,000 yr BP, respectively. When compared to other pollen records from northwestern North America these cores (1) represent

Pollen and radiolarian records from deep-sea core RC 14-103: climatic reconstructions of northeast Japan and northwest Pacific for the last 90,000 years

Aridification of the Namib Desert: evidence from oceanic cores in Antarctic glacial history and world palaeoenvironments.

Study of an ice core to the bedrock in the accumulation zone of an Alpine glacier

One-centimeter interval Pb 210 dating and 4 cm interval size analysis was carried on on sediment core collected in a prodelta depositional environment near the head of Saguenay Fjord. Results show a direct relationship between modal diameter
of the sand fraction and annual maximum mean monthly river discharge-associated with the spring freshet. Clay pellet zones observed in a gravity core are related to catastrophic events such as the 1971 St Jean Vianney landslide or to anthropogenic activities

Les données des carottes de glace de l'Antarctique: évolution du climat et de l'environnement atmosphérique depuis le dernier maximum glaciaire. in Paléoclimats. (Data from Antarctic ice cores: climatic and environmental changes since the last

Deuterium, tritium and activity in a snow core taken on the summit of Mont Blanc (French Alps). Determination of the accumulation rate

Fossil diatom assemblages from a 12-m core from Kirchner Marsh were compared with modern surface assemblages from 159Minnesota and Labrador lakes using cluster analysis. The deepest levels of the core (spruce pollen zone 13,000 to 10,200yr BP

The quantitative distribution of planktonic foraminifera, pteropods, and coccolithophorids, as well as oxygen-isotope variations were analyzed in four deep-sea cores from the Gulf of Aqaba (Elat) and the northernmost Red Sea. The core record covers

Petrographic analysis of Quaternary ferriferous sand layers in eastern Mediterranean cores reveals distinct mineralogical differences between the Egyptian Shelf-Nile Cone region and the southern part of the Mediterranean Ridge. A compositionally
and texturally immature suite in Ridge cores, mixed with a Nile-derived assemblage, identifies a fresh non recycled mineral component derived from proximal igneous and metamorphic surface or near-surface exposures, probably in the south-central Ridge area rather

This tentative approach shows that freshwater diatoms in Atlantic cores may be a good tool for reconstructing paleoclimates and for establishing continent-ocean correlations if species analyses are made and if the continental distribution

The observed close relations between Northern Hemisphere glacier fluctuations and variations in Greenland ice-core acidity suggests that sulfur-rich aerosols generated by volcanic eruptions are a primary forcing mechanism of glacier fluctuations

Chironomid (midge) remains analyzed from an 8.95-m-long sediment core from Marion Lake reveal successional changes over the last 12,000 yr since deglaciation. The response of the chironomid community accords well with paleoclimatic inferences based

Wastage of the Klutlan ice-cored moraines, Yukon Territory, Canada
A series of ice-cored Neoglacial moraines at the terminus of the Klutlan Glacier covers an area of 90 km. Studies were made to determine empirically how long ice persisted in the Klutlan moraines and to develop models that can accurately predict

Three central Arctic Ocean sediment cores were sampled for percentage carbonate, number of foraminifera, and texture. These three parameters were used in spectral analyses to test the idea that the ice-covered Arctic Ocean may respond to orbital
forcing in a different manner than has been indicated for lower latitude ice-free oceans. The record for two of the cores represents approximately 1 my, and the record for the third, approximately 400,000 yr. The 100,000-yr frequency is well represented
in all of the cores. A 40,000-yr frequency may be present, as well. An unexpected 70,000-yr frequency occurs in most of the spectra and may reflect nonlinear sedimentation rates or the combined effect of obliquity and eccentricity. The strong 100,000-yr

Various techniques are used to detect the possible distortion of the tide by the presence of an ice cover at some gauging sites in the Canadian Arctic. Some stations are apparently unaffected, while those around the periphery of Amundsen Gulf

Le micro-climat des centres de villes est plus chaud que celui de la périphérie: causes, caractéristiques, conséquences. (MFP).

This paper presents the results of a marine geological survey of the South Orkney Plateau. Field work for this project was conducted during the austral summer of 1985 and consisted of piston coring and the acquisition of high-resolution (sparker

Résultats de la recherche (133 résultats)