Quaternary Studies in Newfoundland: a Short Review C

Quaternary Studies in Newfoundland: a Short Review C

Document generated on 09/29/2021 12:22 a.m. Atlantic Geology Quaternary Studies in Newfoundland: A Short Review C. M. Tucker Volume 12, Number 2, August 1976 URI: https://id.erudit.org/iderudit/ageo12_2rep02 See table of contents Publisher(s) Maritime Sediments Editorial Board ISSN 0843-5561 (print) 1718-7885 (digital) Explore this journal Cite this article Tucker, C. M. (1976). Quaternary Studies in Newfoundland: A Short Review. Atlantic Geology, 12(2), 61–13. All rights reserved © Maritime Sediments, 1976 This document is protected by copyright law. Use of the services of Érudit (including reproduction) is subject to its terms and conditions, which can be viewed online. https://apropos.erudit.org/en/users/policy-on-use/ This article is disseminated and preserved by Érudit. Érudit is a non-profit inter-university consortium of the Université de Montréal, Université Laval, and the Université du Québec à Montréal. Its mission is to promote and disseminate research. https://www.erudit.org/en/ 61 QUATERNARY STUDIES IN NEWFOUNDLAND: A SHORT REVIEW C.M. TUCKER Department of Geography, McMaster University, Hamilton, Ontario, L8S 4K1 INTRODUCTION portion of the remaining marine drift and left the island with its present contours. During the past century and a half, a consider- After the raising of the great North-East able body of knowledge has been amassed on the and South-East ranges, first coast-ice Quaternary epoch of Newfoundland. Until recently, flowed East and. West and afterwards the studies were of a reconnaissance nature, generally glaciers followed in a similar deviation, incidental to bedrock mapping projects or regional and thus perhaps the origin of the boulders, prospecting. No new information is contained in those which are so curiously perched being this paper; rather, the purpose is to provide an due to the latter than the former. Thus, it extensive, if not complete, list of reference for would seem that icebergs and coast-ice the area and to summarize the salient points preceded glaciers but to say what might presented in the literature. It is hoped that a have come before the former of those agents historic approach will shed light on how specific would only be delving deeper into the depths theories developed and were maintained, while at of a sea of speculation. " the same time re-emphasizing problems that still exist in determining the scope and sequence of In 1882 Alexander Murray compiled the results Quaternary events. Many original ideas such as of his field seasons in Newfoundland, .and presented those of Murray (1864, 1883), Fernald (1911, 1930), them in the form of a new glacial theory. Many of and Coleman (1926) have been obscured by more recent his ideas had been gleaned from Sir William Logan's work, but in spite of improved logistics and research studies around Lake Timiskaming, with whom Murray methods, several questions originally raised by had worked in Ottawa, prior to his appointment to the authors have yet to be resolved. Except for found the Geological Survey of Newfoundland (Baird coastal events, the Quaternary of Newfoundland is, 1975) . Murray proposed that a "sea of ice" flowing still, little understood. down the St. Lawrence River impinged on the west coast of Newfoundland. This, he envisaged from EARLY APPLICATION OP GLACIAL THEORY the "scooping out of great holes" in Humber Arm and supposed terminal and lateral moraines found along As was common for European research of the its banks. Local glaciers occupied Grand Pond period, first accounts of the Ice Age in Newfound- (Lake), Red Indian Lake and Gander Lake, as well as land contained references to the deluge or great numerous other rock basins and deep depressions flood. In a paper read to the Geological Society which occur in the bays. Most of the fiords were of London in 1874, Milne implied that submergence cut by local glaciers flowing toward the northeast, of at least 300 m and ploughing by drift ice from except where deflected by local bedrock structure. the Arctic gave the island's topography its He maintained that uplift of the island was in effect characteristic northeast-southwest lineation. Sub- before the onset of glaciation and continued at a mergence was assumed to have been followed by local discontinuous rate to the present. Murray thus glaciation, which would explain anomalous radial recognized the existence of isostatic rebound though striae and roches perchees that were recorded by in light of modern theory his interpretation of the Jukes (1843) on his excursions through Newfoundland. evidence was only partially correct. Based on In 1876, referring to observations made by Alex- Kerr's (1870) discovery of a terminal moraine across ander Murray of the Newfoundland Geological Survey, the mouth of Conception Bay at a depth of 180 to 255 m, Milne formalized his ideas. Murray hypothesized that a "grand" or terminal moraine for the whole island existed on the Grand Banks from "If Newfoundland has been steadily rising which ice receded back to local glaciers, limited to during the past ages, as it now appears to the high ground. Perhaps of all the early reconnais- have done, at no very remote geological sance workers in Newfoundland, Murray did more to period it may have been beneath the surface interpret field data on the Quaternary in a manner of the ocean. During the period when it was that has some validity, even today. undergoing elevation, no doubt a consider- able amount of debris and boulders were THE OPPOSING THEORIES dropped by icebergs over its surface. When the Laurentian backbone, (Long Range In 1911, Fernald reported on an expedition to Mountains), which would be the first land Newfoundland and Labrador. In it, he proposed that to emerge, reached the surface, it formed the island had remained unglaciated during the a barrier for the coast-ice which would Wisconsinan. His argument (1925) was that plants carry its load of boulders and strew them similar to species of the Western Cordillera, found with those of the bergs. After the final in eastern tablelands and ravines, such as the emergence, the climate of Newfoundland Shickshocks in New Brunswick and the Long Range of might still have been a cold one and the Newfoundland, must have survived in glacial refugia same highlands which gave birth to coast- since they were not found along the Laurentide limit ice probably next gave birth to glaciers of America and throughout much higher mountain ranges which scooped and hollowed out a great in northern New England and New York. His theories MARITIME SEDIMENTS, August 1976, Vol. 12, No. 2, pp. 62 were to be debated in the literature for the next Bequest, in which they devised a series of three two decades, though not from a botanical viewpoint. levels of planation and proposed that the island Daly (1921) provided one of the earliest compre­ had, in fact, been completely glaciated during the hensive studies of isostatic rebound in Newfoundland Wisconsinan. They concluded that: and Nova Scotia. His view was that the zero isobase 1. Newfoundland may have been glaciated by Labrador crossed Newfoundland in St. Georges Bay near Robinsons ice during the Wisconsinan. Head and close to the axis of Bonavista Bay in the 2. In a late phase of the Wisconsinan, the island east. With maximum uplift in the order of 150 m supported its own ice cap, a remnant of which pro­ near Forteau, Labrador, he concluded (1920) that bably occupied the Avalon Peninsula during a de­ his ideas were in agreement with Fernald's since glacial phase. Dispersal centres of late glacial peripheral upwarping in Newfoundland from an ice ice were situated sequentially over the Annieopsquotch dome centered over Labrador would have created a Mountains and the Red Indian Lake area. belt of elevated land extending more or less con­ 3. A slight deglaciation occurred along the south­ tinuously south to New Jersey. Although he obser­ west coast which allowed deposition of fines and ved and noted the influence of foreign ice on glacio-marine sediment. isostatic downwarping of the island, his evidence 4. Following this, a slight re-advance in St. from eastern and central Newfoundland is scanty George’s Bay deposited till and gravel (Robinson's and poorly developed. Coleman (1926) added further Head Drift) over marine beds and earlier drift, support to Fernald's hypothesis. He reported that and formed a "strong continuous moraine from the he could find no evidence for glaciation of the Anguille Mountains to Port au Port". southern part of the Long Range Mountains during the Pleistocene; further, ice that invaded the Tanner (1940) while enroute to Labrador, attempted Northern Peninsula and the rest of the island to resolve the dichotomy posed by the McClintock- was probably of Kansan or Jerseyan age. His argu­ Twenhofel and Fernald-Coleman arguments. From ment was based on evidence of deep weathering and observations made on a brief aeroplane flight from lack of erratics around the Topsails, as well as St. Anthony to Port Saunders he concluded that a dearth of boulder clay and striae at various Laurentide ice had totally over-run the Northern locations around Notre Dame Bay. He concluded Peninsula, including its highest summits "at least that Wisconsinan ice covered less than half the as far south as 50° 30' latitude". This did little, island and was in the form of small separate ice however, to resolve the question posed by Fernald sheets and valley glaciers. Coleman, as did his as to the extent of glaciation in the southern Long predecessors, reported locations of buried and Range. raised Pleistocene shells, many of which have since been re-discovered and variously dated as being 15,000 to 11,000 years old.

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