This paper is a short study of erosion in Norway; first, it includes an analysis of the disposition of the types of relief (plateaus, valley generations). This study brings some precisions about the "paleic surface" and allows, due to a more precise definition of structurally controlled forms and of differential erosion, a better appreciation of the influence of some preglacial features in the landscapes. After this attempt to identify the generations of landforms, the marks made by the major morphogenetic systems are analysed, especially those of glaciers, and of a chemical weathering which, in a few places, could be preglacial. These inherited landforms, the informations brought by some recent geological studies of sediments on the Continental Margin, and the analysis of the degrees of resistance, are used for interpretating the Norwegian landscapes evolution. It is confirmed that the major part of the oblique uplift of Norway is recent (Neo-gene); some stages of the preglacial morphological evolution are also shown.
Ten cores from the Northeast Newfoundland shelf and adjacent continental slope have correlable late Quaternary marine sequences. Late Holocene sediment is olive grey mud, with some ice-rafted debris. The early Holocene is characterised by warmer water microfossil assemblages, abundant ice-rafted carbonate debris, and pollen assemblages indicating open boreal woodland interspersed with tundra. Late and mid-Wisconsinan glacial stades show subarctic planktonic microfossil assemblages, regional sources of tundra pollen, storm reworking of earlier sediment, including till, and shallower water assemblages of benthonic foraminifera and diatoms. Two mid-Wisconsinan interstades are recognised, with marine microfossils similar to the early Holocene. This sequence rests disconformably on earlier (?lllinoian) pro-glacial muds which appear to overlie till.
Current terms such as slikke and schorre are often misused. The author reviews previous studies which have influenced their semantics. The definition of a slikke as given by JACQUET (1949) and VERGER (1968) should be retained; it characterizes well a coastal «habitat» invaded by seed plants. Also, it has been found that the «mean high water» (PMM) can be used to delimit the slikke from the schorre. This tide-mark seems universal, at least in the protected coasts where salt marshes are forming. The second part deals with the plants and soils found in the slikke of Isle-Verte region; this slikke (middle hydrolittoral) is located along the St. Lawrence River at the beginning of the sub-zone polyhaline ß.
The marine cliff of northernmost Chile, about 700 m high and 800 km long, represents a major geomorphic feature of the Earth. North of Iquique it is still an active cliff retreating under wave action but elsewhere it is an abandoned cliff with a wave cut platform lying at its foot. The high cliff probably derives from important fault scarps of Upper Miocene age which have retreated during a major middle to upper Pliocene transgression. It has been only slightly modified by glacio-eustatic oscillations of sea level during Quaternary time. Persistent aridity in spite of some more humid periods also accounts for its good preservation. There is evidence supporting a post-Pliocene subsidence of the coastal area.
Deforestation related to development work in the Swan Hills oilfield has resulted in gullying in road ditches, power lines and pipelines, right-of-ways and on well sites. The study of a large number of these gullies developed in clay and soft shale has made it possible to establish a nomograph to locate erosion control check dams. More importantly, the study suggests research avenues to determine the resistance of poorly consolidated material to erosion by running water.
Three different kinds of periglacial rock mounds are described here: 1) fissured
rock mounds; 2) rock mounds with central or marginal depressions; 3) frost-shattered
rock mounds. These landforms are mainly the results of frost heaving and frost
shattering in different bedrock materials. These processes are presently operating
although they were active in the recent past. The evolution of these periglacial
features depends mostly on the hydric conditions of the fractured bedrock and the
immediate topographic environment.