Ice-work, Present and PastKegan Paul, Trench, Trübner, 1896 - 295 pagini |
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Termeni și expresii frecvente
Alpine Alps amount angular basin beds beneath boulder clay breccias Carboniferous chalk chap cliffs climate coast comparatively considerable contour crags débris descend direction distance district Drift Edition elevation England Eocene erratics favourable feet above sea-level fragments Geol geologists Geology Geology of England glacial deposits Glacial Epoch glaciers Glen Roy granite Greenland ground height higher hills hypothesis Ice Age ice-sheet ice-streams inches indicate inland ice Irish Sea islands Jour lakes land land-ice latitude latter less lower lowlands Malaspina Glacier marine mass material melting miles Moel Tryfaen molluscs moraine mountain nearly neighbourhood névé northern Norway numerous Nunataks occasionally occur parallel pebbles precipitation present probably Professor Quart range region ridges rise river roches moutonnées sands and gravels Scotland shells side slope snow snow-line sometimes southern stones stratified streams striated subangular submergence surface temperature terminal moraine thickness traced upper valley Wales western yards
Pasaje populare
Pagina 59 - It was a beautifully clear evening, and we had a most enchanting view of the two magnificent ranges of mountains, whose lofty peaks, perfectly covered with eternal snow, rose to elevations varying from seven to ten thousand feet above the level of the ocean. The glaciers that filled their intervening valleys, and which descended from near the mountain summits, projected in many places several miles into the nea, and terminated in lofty perpendicular cliffs.
Pagina 75 - ... thus building up their channels and obstructing the outlets of the tunnels. The blocking of the tunnels must cause the subglacial streams to lose force and deposit sand and gravel on the bottom of their channels ; this causes the water to flow at higher levels, and coming in contact with the roofs of the tunnels, enlarges them upwards ; this in turn gives room for additional deposits within the ice as the alluvial cones at the extremities of the tunnels grow in height. In this way narrow ridges...
Pagina 59 - The glaciers that filled their intervening valleys, and which descended from near the mountain summits, projected in many places several miles into the sea, and terminated in lofty perpendicular cliffs. In a few places the rocks broke through their icy covering, by which alone we could be assured that land formed the nucleus of this, to appearance, enormous iceberg.
Pagina 72 - Besides the shells of molluscs, there are the shell-cases of annelids (serpulce?), attached to glaciated boulders, showing that the stones on which they grew must have remained exposed at the bottom of the sea for some time before being wholly buried.