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The study of large erratic boulders casts new light on some glacial palaeogeography problems in the Apuan Alps

The study of large erratic boulders casts new light on some glacial palaeogeography problems in the Apuan Alps
Appennino ; Erratic boulder ; Geochronology ; Glacial features ; Italy ; Palaeogeography ; Spatial distribution ; Toscana
Erratic boulders of glacial origin, mainly made of jasper, marble and cherty limestone, are found in the main valleys of the Apuan Alps. Such boulders are especially widespread in the north-eastern sector of the Apuan Alps, sometimes in great number
, and they bear witness to a 6 km long journey. The types and distribution of the erratic boulders allow one to outline the dimensions of the main glacial bodies and assess the relationships between them. Moreover, the presence of erratic boulders opens new
avenues of research in order to complete the description of the Apuan glaciation and its chronology by using the techniques of exposure age dating, which can be easily applied to erratic boulders. - (NFà.

Boulder depressions in central Sweden. Remnants of a pre-Late Weichselian landscape?

Boulder depressions in central Sweden. Remnants of a pre-Late Weichselian landscape?
Drumlin ; Erratic boulder ; Glaciation ; Moraine ; Palaeogeography ; Periglacial features ; Quaternary ; Sweden
During geomorphological mapping of an area in central Sweden, it was found that areas of boulder depressions tended to be mutually exclusive with drumlinized and Rogen moraine areas of Late Weichselian origin. This irregular erosion pattern probably
reflects the fact that the Late Weichselian ice sheet was partially frozen to its bed. If the situation is the same in other parts of Fennoscandia, boulder depressions may prove to be a helpful feature when searching for warm- and cold-based areas

Boulder deposits from large waves during the last interglaciation on North Eleuthera Island, Bahamas

Boulder deposits from large waves during the last interglaciation on North Eleuthera Island, Bahamas
Aminostratigraphy ; Bahamas ; Coastal dynamics ; Coastal environment ; Erratic boulder ; Interglacial ; Mass movement ; Pleistocene ; Rainstorm ; Stratigraphy ; Tsunami ; Wave
This paper presents a detailed description of the boulders of north Eleuthera and demonstrates that they were deposited by waves during the Pleistocene. It describes the time and stratigraphy related to boulder emplacement, and evaluates tsunamis

Weathering processes on rock surfaces in the Hunza Valley, Karakoram, North Pakistan

Crystalline rocks ; Duricrust ; Erratic boulder ; Karokoram ; Moraine ; Pakistan ; Valley ; Weathering
This paper reports on rock temperature fluctuation in the north and south surfaces of a moraine boulder in Hunza Karakoram obtained over 2 years, and concludes that the rock surface weathering processes depend primarily on the differences

Downslope displacement rates of ploughing boulders in a mid-alpine environment : Finse, southern Norway

Downslope displacement rates of ploughing boulders in a mid-alpine environment : Finse, southern Norway
Erratic boulder ; Freeze-thaw cycle ; Gelifluction ; Global Positioning System ; Mountain ; Norway ; Periglacial features ; Slope dynamics ; Survey
Annual and seasonal displacements of ploughing boulders were investigated at Finse, by traditional surveying and differential carrier-phase global positioning system measurements. Annual displacement rates were mainly below 10mm/year
. There was a tendency for larger boulders to travel faster. Seasonal displacements were restricted to the annual freeze-thaw cycle. The concept of frost creep seems not applicable to the investigated ploughing borders. On the hand, due to tilting of the boulders

Differential rock weathering in the Valley of the Boulders, Kärkevagge, Swedish Lapland

Differential rock weathering in the Valley of the Boulders, Kärkevagge, Swedish Lapland
Chemical erosion ; Cold area ; Differential erosion ; Erratic boulder ; Geochemistry ; Lapland ; Mineralogy ; Sweden ; Weathering

Geomorphological environment of boulders and grain-size analysis of gravel sheets in the Southern Börzsöny, Hungary

Geomorphological environment of boulders and grain-size analysis of gravel sheets in the Southern Börzsöny, Hungary
Erratic boulder ; Geomorphology ; Grain size distribution ; Gravel ; Hungary ; Komáron-Esztergom ; Lithology ; Mountain ; Slope deposit
similarity between the samples collected from the occurrences. In the environment of both locations some boulders are found composed of quartzite. In the opinion of the author these boulders were very probably transported by floating frozen ice floes. - (AM)

Glacial and periglacial deposits of the Tumbledown Cliffs area, James Ross Island, West Antarctica

Antarctica ; Erratic boulder ; Geochronology ; Glacial features ; Kame ; Moraine ; Palaeo-environment ; Periglacial features ; Quaternary
The glacial geology was investigated with the purpose of studying the genesis and chronology of the glacigenic deposits in the Tumbledown Cliffs area on the west coast of James Ross Island. Erratics are evidence of an earlier, more widespread

Chalk micropalaeontology and the provenancing of Middle Pleistocene Lowestoft Formation till in eastern England

Biostratigraphy ; Chalk ; England ; Erratic boulder ; Foraminifera ; Glaciation ; Moraine ; Palaeogeography ; Palaeontology ; Pleistocene ; United Kingdom
sheets. This technique involves extracting foraminifera from Chalk erratics and till matrix obtained from stratigraphically controlled till sections and comparing their micropaleontologywith that of Upper Cretaceous Chalk bedrock. The revised ice-flow

Cosmogenic Be 10 and Al 26 exposure ages of tors and erratics, Cairngorm Mountains, Scotland : timescales for the development of a classic landscape of selective linear glacial erosion

Cosmogenic Be 10 and Al 26 exposure ages of tors and erratics, Cairngorm Mountains, Scotland : timescales for the development of a classic landscape of selective linear glacial erosion
Earth surface processes ; Erosion rate ; Erratic boulder ; Glacial erosion ; Glacial features ; Isotope dating ; Model ; Scotland ; United Kingdom ; Weathering

Matrix granulometry of catastrophic debris flows (December 1999) in central coastal Venezuela

Carrying capacity ; Catastrophe ; Coastal environment ; Erratic boulder ; Flood ; Grain size distribution ; Heavy rain ; Mudflow ; Valley ; Venezuela
) affected by debris flows, and discuss the grain-size distribution with regard to the buoyancy and competence of the debris flows for boulder transport.

Chevron ridges and runup deposits in the Bahamas from storms late in oxygen-isotope substage 5e

Aminostratigraphy ; Bahamas ; Climatic variation ; Coastal dynamics ; Coastal environment ; Coastal geomorphology ; Erratic boulder ; Interglacial ; Rainstorm ; Sea level ; Stratigraphy
On low-lying areas of the Bahamas, extensive V-shaped storm-beach ridges (chevrons in this paper) were emplaced by similar, high-energy events. The origin of these storm ridges, associated run-up features, and boulder deposits, plus the implications

Flared slopes revisited

Australia ; Coastal geomorphology ; Erratic boulder ; Fracture ; Inselberg ; Slope ; Soil erosion ; South Australia ; Weathering
Flared slopes are smooth concavities caused by subsurfacemoisture-generated weathering in the scarp-foot zone of hillslopes or boulders. They are well represented in granitic terrains but also developed in other massive materials such as limestone

Die Eiszeitgeschiebe in der Umgebung von Leipzig (Les blocs erratiques glaciaires dans les environs de Leipzig)

The results of an almost 100 years lasting research on fossiliferous sedimentary and cristalline erratic boulders at the marginal zone of the Scandinavian glaciation with the boulder association of various basal tills, of the reconstructed ice

Paleo-periglacial ventifact formation by suspended silt or snow, site studies in South Sweden

Aeolian features ; Erratic boulder ; Micromorphology ; Periglacial features ; Shoreline ; Snow ; Sweden ; Weathering

The application of lichenometry in dating of glacier deposits

Cold area ; Dating ; Erratic boulder ; Glacial features ; Greenland ; Lichenometry ; Moraine

Problèmes actuels de morphomontologie (géomorphologie des montagnes)

Deglaciation ; Erratic boulder ; Geomorphology ; Glacial deposit ; Glacial erosion ; Glaciation ; Glacier ; Mountain ; Thermokarst

Windpolished boulders as indicators of a Late Weichselian wind regime in Denmark in relation to neighbouring areas

Windpolished boulders as indicators of a Late Weichselian wind regime in Denmark in relation to neighbouring areas
Aeolian features ; Denmark ; Erratic boulder ; Ice sheet ; Palaeo-environment ; Quaternary ; Spatial variation ; Wind ; Wind erosion

Frost heave and thaw consolidation of ploughing boulders in a Mid-Alpine environment, Finse, Southern Notway

Frost heave and thaw consolidation of ploughing boulders in a Mid-Alpine environment, Finse, Southern Notway
Cold area ; Erratic boulder ; Freezing ; Heat transfer ; Norway ; Statistical analysis ; Thawing ; Vertical movement

Les cordons de blocs frangeants (boulder barricades). Mise au point avec exemples du Québec

Les cordons de blocs frangeants (boulder barricades). Mise au point avec exemples du Québec
Canada ; Coastal dynamics ; Coastal environment ; Cold area ; Erratic boulder ; Estuary ; Floating ice processes ; Foreshore ; Palaeo-environment ; Quebec ; Saint-Laurent ; Sand bar

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