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The boulder fields of Mt. Fulufjället, west-central Sweden
  • The boulder fields of Mt. Fulufjället, west-central Sweden
  • Detailed morphological analysis of the boulder fields on the Mt Fulufjället plateau has revealed three morphologically and genetically different boulder field types| 1) boulder depressions related to up freezing in till| 2) boulder blankets| i.e
  • . glacially transported boulder masses, and 3) frost-shattered debris in situ. No large-scale periglacial forms appear to have developed on the plateau during the Holocene. An area of more than 60 km2 of an interstadial periglacial landscape has survived
A note on the vertical distribution of boulder fields in the archipelago of Åland (Ahvenanmaa)
  • A note on the vertical distribution of boulder fields in the archipelago of Åland (Ahvenanmaa)
  • Boulder field ; Coastal environment ; Fluvioglacial features ; Periglacial features ; Sea level ; Sedimentary ; Spatial distribution ; Sweden
  • The distribution of boulder fields situated in three different parishes in Åland is discussed. It has been found that the majority of the boulder fields are situated at altitudes that correspond to Ancylus-transgressions and an early Litorina
The stone and boulder content of Swedish forest soils
  • The stone and boulder content of Swedish forest soils
  • Stone and boulder content has a strong influence on many soil processes and is a crucial factor to take into account when estimating element pools. In this paper, the AA. present the results of a large scale inventory of the stone and boulder
  • content of forest soils, which employed a surface penetration method (Viro's method) in 1943 plots across Sweden. A relationship was found between stone and boulder content and surface boulder frequency, but the strength of the relationship varied
  • regionally. In some regions surface boulders may provide an indicator of stone and boulder content in the soil.
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 trail from a subglacial earthquake, Äspö, Sweden
  • Boulder trail from a subglacial earthquake, Äspö, Sweden
  • A subglacial earthquake has been defined by a palaeoseismic boulder trail and associated primary and secondary fault and fracture structures. It occurred a few years before final deglaciation, which occurred some 12,000 years BP. A palaeoseismic
  • boulder trail from a subglacial earthquake represents a new type of palaeoseismic phenomenon not previously described.
Enhanced boulder weathering under late-lying snowpatches
  • Enhanced boulder weathering under late-lying snowpatches
  • This communication reports the results of research undertaken at sites in Switzerland, Scotland and Norway to determine whether boulders buried by late-lying snowpatches show signs of increased surface wheathering when compared with boulders
The recurrence of large boulder movement in small watersheds of the Anza Borrego Desert, California
  • The recurrence of large boulder movement in small watersheds of the Anza Borrego Desert, California
  • Boulders in three small drainage bains of the Anza Borrego Desert were studied. The precipitation intensity and critical velocity of water flow required to move the boulders, relicts of the Pleistocene, were calculated. As the rainfall intensities
  • must approach or exceed the probable maximum precipitation, the boulders may be considered virtually permanent features of the ephemeral stream channels. - (SLD)
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
Assessing volumetric strains and mass balance relationships resulting from biotite-controlled weathering: Implications for the isovolumetric weathering of the Boulder Creek Granodiorite, Boulder County, Colorado, USA
  • Assessing volumetric strains and mass balance relationships resulting from biotite-controlled weathering: Implications for the isovolumetric weathering of the Boulder Creek Granodiorite, Boulder County, Colorado, USA
  • Biotite ; Boulder County ; Colorado ; Erosion chimique ; Etats-Unis ; Granodiorite ; Géochimie ; Minéralogie ; Météorisation
  • The AA. present results from a study of two sites located on the 1.65 Ga Boulder Creek Granodiorite near Boulder, Colorado, USA, in which weakly chemically altered saprock derived from tonalitic and granodioritic–tonalitic bedrock records volumetric
Boulder deposition during major tsunami events
  • Boulder deposition during major tsunami events
  • Algarve ; Boulder ; Coastal environment ; Eighteenth Century ; Hydrodynamics ; Modelling ; Palaeogeography ; Portugal ; Sediment transport ; Tsunami
  • A remarkable accumulation of marine boulders located above the present spring tide level has occurred in 2 coastal lowlands of the Algarve (Portugal). The spreads of boulders extend several hundred meters inland and well beyond the present landward
  • limit of storm activity. The marine origin of the boulders is demonstrated by well-developed macro-bioerosion sculpturing and in situ skeletal remains of endolithic shallow marine bivalves. The good state preservation of the fossils within the boulders
  • indicates that abrasion during transport and redeposition was not significant. The AA. envisage boulder deposition as having taken place during the Lisbon tsunami of AD 1755. The AA. use numerical hydrodynamic modeling of tsunami (and storm) waves to test
  • the observational data on boulder dimensions (density, size, distribution) on the most likely processes of sediment deposition. This work demonstrates the effectiveness of the study of boulder deposits in tsunami reconstruction.
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
Some observations on boulder-cored frost boils
  • Some observations on boulder-cored frost boils
  • Actuel ; Boulder-cored frost boil ; Boverbreen, glacier ; Butte à blocaux ; Cryopédologie ; Cryoturbation ; Gphy ; Granulométrie ; Géographie physique ; Géomorphodynamique ; Jotunheimen, mont ; Microrelief ; Moraine ; Norvège ; Périglaciaire
The boulder beach: a fundamentally distinct sedimentary assemblage
  • The boulder beach: a fundamentally distinct sedimentary assemblage
  • Australie ; Boulder ; Caillou ; Galet ; Gphy ; Gravier ; Géographie de l'Océanie ; Géomorphologie littorale ; Littoral ; New South Wales ; Plage ; Plage à galet ; Sédimentologie
A glacial chronology for the Fish Creek drainage of Boulder Mountain, Utah, USA
  • A glacial chronology for the Fish Creek drainage of Boulder Mountain, Utah, USA
  • In this study, the AA. use cosmogenic He 3 exposure-age dating to determine emplacement ages of boulders from the most prominent moraines in the Fish Creek drainage of Boulder Mountain. They develop a simple correction for their exposure-ages using
Stream bed stabilization using boulder check dams that mimic step-pool morphology features in Northern Italy
  • Stream bed stabilization using boulder check dams that mimic step-pool morphology features in Northern Italy
  • In this article, construction designs currently used for boulder check dams will be described. An example of their planning and design according to geomorphological and stream bed stabilization criteria will be given, with reference to an artificial
  • step-pool sequence structure constructed with large boulder in the Province of Trento, North Italian Alps.
The upper Pite River valley. A study of large boulder deposits and catastrophic floods.
  • The upper Pite River valley. A study of large boulder deposits and catastrophic floods.
A comment on enhanced boulder weathering under late-lying snow patches by Ballantyne, C. K., Black, N. M., and Finlay, D. P.
  • A comment on enhanced boulder weathering under late-lying snow patches by Ballantyne, C. K., Black, N. M., and Finlay, D. P.
Use of the Schmidt test hammer to detect enhanced boulder weathering under late-lying snowpatches
  • Use of the Schmidt test hammer to detect enhanced boulder weathering under late-lying snowpatches
New perspectives on colluvial boulder deposits in the southwestern Great Basin, USA
  • New perspectives on colluvial boulder deposits in the southwestern Great Basin, USA
  • Colluvial boulder fields are ubiquitous on desert hillslopes in the Basin and Range Province. Five chronometric methods indicate that colluvial boulder fields in this region have been active in the late Pleistocene and Holocene. A new method
  • is presented to constrain the ages of colluvial boulder fields, using the presence of stable rock varnish and 36Cl. Rather than interpreting colluvial deposits from the traditional desert geomorphology framework of relict or active, the AA. suggest