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The paper reviews the Precambrian and Paleozoic stratigraphy and structure of New Brunswick against the background of the theory of plate tectonics. The major subdivisions of the Appalachian-Caledonian orogenic belt are examined and a conclusion is reached that as a result of successive Penobscot, Taconic and Acadian orogenic disturbances parts of Paleoamerica and Paleoeurope are so sutured that the formerly intervening oceanic crust has either been entirely obducted onto the continents or subducted below them. The evolution of the orogenic belt in New Brunswick and adjacent regions can be explained with reference to the formation of successive volcanic arcs.
From the papers presented at the Symposium it appears that the geology of the Quebec Appalachians has been subjected to considerable changes these last few years. Logan's line or fault is now spread flat under a series of nappes and slices that constitutes a huge allochthon that extends from the US border to the tip of Gaspé Peninsula and was shoved over a platform that extended much farther south than had been previously assumed- The asbestos-rich serpentinite belt of the Eastern Townships has become an ophiolite complex several kilometres thick, complete with pelagic siliceous sediments. It has been emplaced by obduction. Bordering breccias are seen as trench mélanges related to plate consumption.
The Taconian orogeny, different in style and extension from the Acadian orogeny, is ascribed to a phase of contraction that climaxed in Middle Ordovician and ceased in Late Ordovician. The Acadian orogeny is an altogether different episode that is not easily tied up with the previous Ordovician diastrophism. It can hardly be fitted in the plate tectonics scheme.
Late rift valley tectonism is invoked to explain the Late Paleozoic - Early Mesozoic successor basin of mostly continental deposits that centres on the Gulf of St. Lawrence but that the rifting extended later to the St. Lawrence valley, as has been infered from the normal faulting recognized in the valley, is not readily accepted. It appears that this faulting is the origin of the Cambro-Ordovician exogeosyncline that received the allochthon but that it ceased with the Taconian contraction.
Glaciology and glacial hydrology (the study of the melt waters from glaciers) have not received attention in Canada in proportion to the extent of the country's glaciers. By contrast, Scandinavia has a long tradition of scientific studies, greatly accelerated in recent years by the utilization of melt waters for hydroelectric production. The possibility of increased hydroelectric power production from glacial waters in Canada, and the environmental problems this might involve, motivated Carleton University's course in glacial hydrology. The course is given by Dr. Gunnar (Pstrem who has been in charge of Norwegian glaciological studies in relation to that country's power production. The nature of the course given at Peyto Glacier is discussed, and questions of responsibility for providing expertise in a rapidly developing field are considered.
Limnogeology continues to account for a significant part of the research reported in the annual Conferences on Great Lakes Research. At this year's meeting tie emphasis was on stratigraphie studies of post-glacial sediments, surface sediment geochemistry and shore processes. This is a reflection of current practical concerns with sediment loading, "cultural enrichment" of sediments and accelerated shore erosion.
The portable scintillation counter as first used in prospecting for uranium was a distinctly Canadian invention, as was also the portable geiger counter which preceeded it- Its use as a geophysical instrument was an instant success. The Canadian Patent Office was at that time inundated with patent applications on improvements in ionization chambers and geiger counters but with the advent of the scintillation counter most applications concerning counters using gas in their detecting process ceased abruptly, they were obsolete. With a counting rate a hundred times or more above that of gas counters and its ability to discriminate gamma ray energy, the scintillation counter was quickly adopted for oil well logging, airborne and ground radioactivity surveys as well as expanded scientific research and medical applications. Much of the rapid advance in the field of radioactivity since 1950 is due to the scintillation counter.