Marginal Moraines Research Articles

Late and Middle Weichselian stratigraphy of Andøya, north Norway

BOREAS Vorren, K.‐D. 1978 03 01: Late and Middle Weichselian stratigraphy of Andøya, north Norway, Boreas, Vol. 7, pp. 19–38. Oslo. ISSN 0300–9483.Bio‐stratigraphy and 14C datings from Lake Endletvatn, 69o 44'N and 19o05'E, approx. 35 m above sea level, suggest that the lacustrine sedimentation started about 18,000 B.P. The Middle Weichselian vegetation was probably a dry arctic, partly barren, grassland type with abundant Draba spp. and perhaps also Braya spp. Two climatic ameliorations of this chronal substage, named Endletvatn thermomers 1 and 2 (ET 1 and 2), have been recorded. During ET 2, the beginning of which has been dated at about 15,000 B.P., a humid climate prevailed, with a July temperature probably not deviating much from the present one. The colonization by low alpine and subalpine species probably started in the Bølling Chronozone. During the early Allerød Chronozone, protocratic conditions with grasses RumexlOxyria, Papaver and Sagina of. saginoides prevailed. During the middle of the Allerød, stable soil and continuous vegetation was established at sheltered places. At the transition to the Younger Dryas Chronozone a climate favouring Artemisia changed this vegetational development. The middle of the Younger Dryas was cool and humid, probably with an upper low alpine vegetation. The end of this chronozone was characterized by a vegetation of low alpine heaths with Empetrum and Dryas.Diatom analysis (Foged 1978) suggests that there has been no direct marine influence in the basin. The marginal moraine stratigraphy, the marine limit and the climatic development are discussed.

Socioprofessional structure of the population of the USSR and its employment pattern

The Pyoza River area in the Arkhangelsk district exposes sedimentary sequences suitable for study of the interaction between consecutive Valdaian ice sheets in Northern Russia. Lithostratigraphic investigations combined with luminescence dating have revealed new evidence on the Late Pleistocene history of the area. Overlying glacigenic deposits of the Moscowian (Saalian) glaciation marine deposits previously confined to three separate transgression phases have all been connected to the Mikulinian (Eemian) interglacial. Early Valdaian (E. Weichselian) proglacial, lacustrine and fluvial deposits indicate glaciation to the east or north and consequently glacier damming and meltwater run-off in the Pyoza area around 90–110 ka BP. Interstadial conditions with forest-steppe tundra vegetation and lacustrine and fluvial deposition prevailed at the end of the Early Valdaian around 75–95 ka BP. A terrestrial-based glaciation from easterly uplands reached the Pyoza area at the Early to Middle Valdaian transition around 65–75 ka BP and deposited glaciofluvial strata and subglacial till (Yolkino Till). During deglaciation, laterally extensive glaciolacustrine sediments were deposited in ice-dammed lakes in the early Middle Valdaian around 55–75 ka BP. The Barents–Kara Sea ice sheet deposited the Viryuga Till on the lower Pyoza from northerly directions. The ice sheet formed the Pyoza marginal moraines, which can be correlated with the Markhida moraines further east, and proglacial lacustrine deposition persisted in the area during the first part of the Middle Valdaian. Glacio-isostatic uplift caused erosion followed by pedogenesis and the formation of a deflation horizon in the Middle Valdaian. Widely dispersed periglacial river plains were formed during the Late Valdaian around 10–20 ka BP. Thus, the evidence of a terrestrial-based ice sheet from easterly uplands in the Pyoza area suggests that local piedmont glaciers situated in highlands such as the Timan Ridge or the Urals could have developed into larger, regionally confined ice sheets. Two phases of ice damming and development of proglacial lakes occurred during the Early and Middle Valdaian. The region did not experience glaciation during the Late Valdaian.

Moraines of the St. Lawrence Valley

Two marginal moraines, the Albion and the Oswego, lying near Lake Ontario and belonging to the recessional series of western New York, were traced with substantial continuity from previously determined points near Rochester to the vicinity of Watertown, and to points farther northeast, where they were lost in the Adirondack forest. Four later moraines of the same series, passing near Watertown, Philadelphia, Gouverneur, and Dekalb, respectively, were followed with some few breaks from the region of Watertown northeast toward the Champlain-St. Lawrence watershed, which passes close to the village of Churubusco. Three of them were followed across the divide and southward along the Lake Champlain slope to the hills northwest of Plattsburg. Part of a still later moraine was found on the Champlain slope. These moraines mark successive re-advance positions of the ice front as it retreated from the basin of Lake Ontario and down the St. Lawrence Valley. They cover the entire duration of Glacial Lake Iroquois and...

Drumlins and marginal moraines of ice-sheets

Introduction. The chief characteristic of the present stage of investigations of the Ice age and its glacial and modified drift deposits seems to consist in the search, through observations and study, for explanations of the methods in which the ice-sheets of North America, northern Europe, Patagonia, and other glaciated areas, acted in eroding, mingling, transporting and depositing the various drift formations. All the diverse phases of the till or ground moraine, also called boulder-clay, from its heterogeneous materials, and including much englacial drift, which was allowed to fall loosely on the ground from the ice during its stages of retreat, are classed together as direct products of the action of land ice, without modification by the assorting, transporting and stratifying agency of streams and lakes formed by the glacial melting and accompanying rains. Most drumlins in their entire mass, and all others in their superficial part, consist of till, an . . .

The succession of Pleistocene Formations in the Mississippi and Nelson River Basins

Research Article| January 01, 1893 The succession of Pleistocene Formations in the Mississippi and Nelson River Basins Warren Upham Warren Upham Search for other works by this author on: GSW Google Scholar GSA Bulletin (1893) 5 (1): 87–100. https://doi.org/10.1130/GSAB-5-87 Article history first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Warren Upham; The succession of Pleistocene Formations in the Mississippi and Nelson River Basins. GSA Bulletin 1893;; 5 (1): 87–100. doi: https://doi.org/10.1130/GSAB-5-87 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search nav search search input Search input auto suggest search filter All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract Introduction.During fourteen years, since June 9, 1879, my field observations and constant studies, successively for the geological surveys of Minnesota and of the United States, have been directed chiefly to the glacial and modified drift of Minnesota, northern, central and northwestern Iowa, the eastern borders of South Dakota, nearly all of North Dakota, excepting the country southwest of the Missouri river, and the large prairie portion of Manitoba. These areas comprise the upper part of the Mississippi basin, the whole district drained by the Red river of the North above the city of Winnipeg, and the lower part of the basin of its large western tributary, the Assiniboine, the two last named streams being portions of the Nelson river system, sending their waters through lake Winnipeg and the Nelson to Hudson bay.In mapping the marginal moraines of the Minnesota and Iowa lobe of the ice-sheet, the first and . . . This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not currently have access to this article.