The article gives a brief summary of till investigations in Sweden, which have long traditions. The main types of till and moraine forms occurring in Sweden are briefly defined and the till stratigraphy is described. A main part of the article
Processer og till fabric i et recent dodislanskab ved Hofdabrekkujokull, Island. (Processus et structure d'un till sur glaces mortes, Hofdabrekkujokull, Islande)
Cône d'ablation ; Fluvioglaciaire ; Glace morte ; Glaciaire ; Géographie de l'Europe ; Hofdabrekkujokull ; Islande ; Sédimentologie ; Till
Examen minutieux d'un till d'écoulement évoluant sur glaces mortes. Grande variabilité des orientations des grands axes des galets. (JCB).
Till variation in a Weichselian glacial section along the coast of south West Funen, Denmark
In a 5 km long coastal cliff section the presence of two till units separated by stratified sands and gravel is apparent. The lower till unit is a basal till. In the upper till unit four different facies are present: two flow till facies
Athabasca Glacier, Canada - a field example of subglacial ice and till erosion ?
The Athabasca Glacier provides an excellent example of subglacial ice and till erosion. The presence of a thin mobile till layer is shown by the presence of flutes, saturated till layer, push moraines and ploughed boulders. Cross-cutting striations
, v-shaped striations and reversed stoss-and-lee clasts are indicative of clasts rotating within this layer. As the till moves it erodes the bedrock and clasts within it. combination of erosion by ice and till produces stoss-and-lee-clasts
Distribution and genesis of tills in Central South Norway
The morphogenesis of tills below the culmination zones of the Weichselian inland ice has been studied in an upland area with a relief of 1500m. The thickness of the tills varies considerably, depending principally on geomorphology, ice-movement
directions, and glaciofluvial drainage during the last deglaciation period. The thickest tills, found in valleys, accumulated in three ways. Glaciofluvial/lacustrine sediments of presumed Mid-Weichselian age have been discovered beneath the tills at more than
10localities. The overlying tills are correlated with different phases of ice movement reconstructed on the basis of detailed studies of striae. The till stratigraphy of one locality, Stenseng, is described in detail. Based upon combined analyses of texture
, structure, and fabric, four different basal tills are recognized, each corresponding to a particular ice direction. A characteristic boulder layer represents a change in the direction of glacial movement. Boulder layers in till are thought to be essential
Clast-fabric strength in tills and debris flows compared for different environments
Allemagne de l'Ouest ; Allgäu ; Glaciaire ; Géographie de l'Europe ; Moraine ; Pays-Bas ; Quaternaire zones moyennes ; Till fabrique
Elongated-clast fabrics of Alpine till from western Allgäu and of lowland ice-sheet till from the Netherlands are compared with published results from other areas. A quantitative comparison is made through the use of an eigenvalue method which
Regional significance of pre-Wisconsinan till from Nantucket Island, Massachusetts
A major pre-Wisconsinan glacial event is the only possible source of the lower till on Nantucket Island, Massachusetts. The till occurs near the late Wisconsinan drift border and below fossiliferous marine beds of oxygen-isotope stage 5 (Sangamonian
) age. It is considered to be Illinoian in age, but the evidence is tenuous. The till is correlated with the lower till of New England, and its presence supports the view that the New England upper and lower tills represent two glaciations. The pre
-Wisconsinan (lower) till in New England may correlate with older tills elsewhere in the northeastern United States and in southeastern Canada that are considered to be early Wisconsinan or older in age.
First, the till fabrics from both modern and ancient, soft bed and hard bed subglacial environments are investigated, and then soft bedded sites with specific strain histories are examined. The results indicate that lodgment tills had a strong
fabric, whilst there is a wide range of much weaker fabric strengths associated with soft bed tills. It is suggested from a theoretical study of soft bed till deposition that longitudinal and vertical processes in the subglacial deforming layer
Au Wisconsinien, l'inlandsis laurentidien a formé trois tills sur l'île d'Anticosti. Dans le premier (Till de la rivière à la Patate) mise en évidence d'un écoulement glaciaire vers le sud-est. Les deux autres tills (Till de la rivière Jupiter et
Till de l'île d'Anticosti) datés du Wisconsinien moyen et supérieur, indiquent un écoulement vers le sud ouest.
Soil development in till of various ages in northeastern Pennsylvania
Eleven well-drained soils formed in till parent materials of varying ages in northeastern Pennsylvania were studied to determine changes in the soils with time. Four profiles (three Lackawanna and one Bath) were formed in Woodfordian till (15,000 yr
B.P.), and two (Leck Kill) were formed in Altonian till (>28,000,
Importance of the regelation process to certain properties of basal tills deposited by the Laurentide ice sheet in Iowa and Illinois, USA
Calotte glaciaire ; Ecoulement sous-glaciaire ; Etats-Unis ; Géographie de l'Amérique ; Illinois ; Iowa ; Lithologie ; Moraine de fond ; Quaternaire zones moyennes ; Stratigraphie ; Sédimentologie ; Till
Recent stratigraphic studies have characterized the sequence and nature of tills deposited in Iowa and Illinois by Quaternary Laurentide ice sheets. Basal tills within the sequence are each dominated by matrix-size materials and exhibit uniform
matrix properties over hundreds or thousands of square kilometers. This uniformity suggests that matrix-size materials were effectively mixed for each basal till.
Chalk micropalaeontology and the provenancing of Middle Pleistocene Lowestoft Formation till in eastern England
A new till provenancing technique based on Chalk micropaleontology is described with the object of refining understanding of the ice sheet which deposited the Lowestoft Formation till (Anglian/Elsterian) and its relationship to Scandinavian ice
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
Weichselian till stratigraphy in central south Norway in Moraines and varves. Origin/Genesis/Classification.
Action glaciaire ; Argile à blocaux ; Fluvioglaciaire ; Glaciaire ; Gudbrandsdalen ; Géographie de l'Europe ; Norvège ; Opland ; Pléistocène ; Quaternaire zones froides ; Stratigraphie ; Till
Résultats d'une recherche stratigraphique sur le till d'un affluent du Gudbrandsdalen et reconstitution des flux glaciaires quaternaires dans la région. (CG).