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  • Charmeled Scabland ; Columbia River basin ; Etats-Unis ; Géographie de l'Amérique ; Hydrodynamique ; Jokulhlaup ; Montagne ; Paléohydrodynamique ; Paléohydrologie ; Pléistocène supérieur ; Quaternaire zones moyennes ; Rocky Mountains
  • Missoula, research since 1960 emphasized details of flood magnitudes frequency, routing and number. Major advances have been made in the study of low-energy, rhythmically bedded sediments that accumulated in flood slack-water areas.
  • Correlation of the Rockland ash bed, a 400,000-year-old stratigraphic marker in northern California and western Nevada, and implications for Middle Pleistocene paleogeography of central California
  • California ; Etats-Unis ; Géographie de l'Amérique ; Géomorphogenèse ; Nevada ; Paléogéographie ; Pléistocène moyen ; Rockland ash bed ; Stratigraphie ; Téphrochronologie
  • Stratigraphic relations of the Rockland ash bed and older tephra layers in the Great Valley and near San Francisco suggest that the southern Great Valley emerged above sea level about 2 my ago, that its southerly outlet to the ocean was closed
  • Carbonate till as a soft bed for Pleistocene ice streams on the Canadian Shield north of Lake Superior
  • A Mazama tephra marker bed in the Fraser Lowland, British Columbia
  • Interglacial beds at Toronto, Ontario in The Last? Interglaciation in Canada : Le dernier (?) interglaciaire au Canada.
  • Near Summer Lake in southern Oregon, 54 tephra beds of late Quaternary age are exposed in pluvial lake sediments of lake Chewaucan. Seven of the tephra beds near the top can be correlated with tephra deposits younger than 117,000 yr at Mount St
  • . Helens, Washington, at Crater Lake, Oregon, and in northwestern Nevada in the deposits of pluvial Lake Lahontan. These seven tephra beds are from 6800 to about 90,000 yr old. Extrapolation of these ages through assumption of constant depositional rate
  • segments, frequently beginning at moulin kames and terminating at the head of outwash fans. The dominant source of the water responsible for tunnel-valley formation was seasonal meltwater from the glacier surface that reached the bed through moulins
  • This study suggests that the complex sequence of Cenozoic shell beds exposed in southwestern Florida can be dated in a high resolution manner by a combination of geochronologic methods, including magnetostratigraphy, strontium-isotope ratios
  • Dating or correlation of buried soils and volcanic ash beds as well as interpretation of magnetic polarity data provide a general time framework to begin a new synthesis of the early and middle Pleistocene history of the region.
  • 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
  • The Trego Hot Springs tephra bed is a silicic tephra about 23,400 yr old, found at several localities in pluvial lake sediments in northern Nevada, southern Oregon, and northeastern California. It has been characterized petrographically
  • Journal of Research, 3, 329-335) on the basis of field relations, Fe-Mg phenocryst assemblage, and C chronology and are valuable marker beds for regional stratigraphic studies. In this study modal abundances and mineral compositions were determined (via