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No. 1033.

GEOGRAPHICAL CONSIDERATIONS AS TO THE CANADIAN-NEWFOUNDLAND BOUNDARY IN LABRADOR.

BY PROFESSOR J. W. GREGORY, F.R.S., D.SC.

I. THE LABRADOR COASTAL BELT A “ DISTINCT GEOGRAPHICAL ENTITY.”


The Geography of Labrador presents two striking contrasts between the eastern and western parts. The first contrast is between the fiord-indented Atlantic coast and the comparatively even shore of Hudson Bay. The second contrast is between the rugged mountainous belt along the Atlantic coast and the undulating plateau which extends westward from the Atlantic coastal belt to Hudson Bay. These contrasts both depend upon geographical features, and not on geological composition, for Labrador consists of one vast. slab of ancient rocks, which are among the oldest known to geologists.

A. GEOLOGICAL ANTIQUITY OF THE PENINSULA.

“ Labrador,” says Packard ('Labrador Coast,' 1891, p. 279) “ is an oblong mass of Laurentian rocks.” E. M. Kindle (Mem. Geol. Surv. Can., 1924, No. 141, p. 56 and fig. 4) has recently doubtfully suggested that some of the sandstones may be Cambrian ;* but that identification, if confirmed, would only extend the range to the earliest division of the succeeding group. After these primeval rocks the next deposits known in Labrador are the glacial beds, sea beaches, and river terraces, which all belong to the most recent geological period. Between these first and last chapters in the geological record nothing is known of Labrador except from indirect evidence, which shows however that it was once part of a much larger land that extended westward and also eastward into the Atlantic.
Geographically also Labrador is simple. It consists of a great plateau which presents a steep front to the Atlantic, and on the western side slopes more gradually downward to Hudson Bay. Most of the plateau is between 1,000 and 1,500 ft. above sea level ; the highest extensive area is in the upper part of the basin of the Hamilton River at about 1,800 ft. The rise inland from James Bay is gentle ; the coast in the northern part of Hudson Bay is usually bold, and the ascent inland to the height of about 500 ft. is steeper than near James Bay ; on the Atlantic side the ascent is abrupt to the height

* Kindle calls them “ Cambrian ?” as they were so named by Low ; R. Bell (1895, p. 35) stated that these sandstones “ bear a close resemblance to the Animikie,” which are now included in the pre-Cambrian, but were regarded as Cambrian in Low's time.

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of 1,000 to 4,000 ft. Most of the western plateau consists of undulating moorland, with the hills rising not more than about 500 ft. above the general level, with broad valleys, and with innumerable lakes in shallow depressions.


B. THE COASTAL CHAIN OF EASTERN LABRADOR

In contrast to the gentle undulations of the western plateau the eastern belt consists of rugged mountains which rise to the greatest height found anywhere along the Atlantic coast of North and South America. They reach a height which, according to Professor Daly (1902, p. 233) is at least 7,500 ft., and is the “ most lofty land immediately adjacent to the coast in all the long stretch from Baffin Land to Cape Horn ” (Daly, 1909, p. 102). These mountains are the remnants of an ancient mountain chain, which has now been broken up into detached ranges situated along the coastal region. These ranges in order from north to south are the Torngat Mountains between Cape Chidley and Hebron, which rise to the height of from 3,000 to 7,500 ft., and face the Atlantic in precipitous cliffs. The second group are the Kaumajet Mountains, or Shining Mountains, near Cape Mugford, a little south of lat. 58°. The third block is the Kiglapait Mountains (or Saw-Tooth or Sierra Mountains) from behind Cape Mugford to behind Nain : they rise from the shore to 2,500 ft. and include summits of 4,000 ft. Further south the highest summits are in the Kokkok Mountains, 4,500 ft. to the north of Hamilton Inlet, and to the south of it in the Mealy Mountains, which Mr. E. N. Kindle has shown are twice as high as was thought and include several summits of over 3,000 ft. and one of 3,800 ft. The three northern ranges form, according to Professor Daly (Joint Appendix, p. 2537) “ an almost continuous mountain land.“ Taken as a whole,” says Professor Daly (Ibid, p. 2537) “ the Nain-Kiglapait-Kaumajet-Torngat Mountain group is a distinct entity, a distinct topographic province of the Labrador Peninsula.”
The essential feature of this distinctness is the mountain structure which, as Prof. Daly has shown (1909, pp. 88-89), continues all along the coastal region of eastern Labrador. The difference between the western plateau and the mountain group in the Northern part of the coastal region continues to the south, though it is less clear there, as between the northern mountain group and the mountains rising to 4,500 ft. near Hamilton Inlet the country is less well known. Some maps, however, indicate the existence of high intermediate mountains. Packard's general map of Labrador (1891, opp. p. 232) shows high “ wooded Mountains ” south-west of Hopedale which represent the coastal mountain chain. Further south his map of 1888 (reprinted Packard, 1891, opp. p. 90) marks Mount Allaigaigai, 2,170 ft. north of Hamilton Inlet and opposite Mount Cabot, 1,482 ft., which is at the eastern end of the Mealy Mountains. According to Dr. Robert Bell (1895, p. 340), formerly Director of the Geological Survey of Canada, Hamilton Inlet, and not the country west of Nain, marks the division between the less regular southern and the more regular northern parts of the eastern

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mountains. He states that the chain is “ scattered and ill-defined from the Straits of Belle Isle to Hamilton Inlet, but northward of this great fiord it becomes more regular.”*
The geographical character of eastern Labrador is determined mainly by the structures due to this ancient mountain chain. Its former existence and influence on the present topography is shown by the strike of the rocks, in accordance with which Professor Daly's Map (1909, fig. 13, p. 88) marks “ the Labrador Trend ” as extending behind the coast all the way from near Cape Chidley to the Strait of Belle Isle. That figure, Professor Daly remarks (1909, p. 89) “ is intended to show that there is a definite trend of the rocks of the Basement Complex, and that this trend has a remarkable parallelism with the present north-east coast of the peninsula.” Daly had previously pointed out (1902, p. 234) in a discussion of “ the general structure of the Coastal Belt,” that the Archean shield [i.e. the area of Archean rocks which forms the foundation of eastern Canada] is rather definitely framed on the border, and that the average direction of the coast-line is related to the tectonic trend of the ancient mountain-system of which the Labrador Plateau is a diminished remnant.” The evidence for the continuity of the strike in the rocks is even stronger than appears from Professor Daly's list (1902, p. 235, 1909, p. 88), for he states that the parallel strike of the schists was often seen from the schooner at other places. He remarks (Daly, 1902, p. 234) “ The impression thus gained is sufficient to warrant our regarding the fidelity of the structure to a general north-west to south-east trend as of a higher order than is shown in the table or in the sketch map.” This ancient mountain chain was formed when the rocks were given their strike parallel to the Labrador coast. The mountain chain was subsequently worn down to a plain. The present coastal mountains are due to re-elevation along the lines of the ancient mountain chain. This comparatively modern uplift produced, in the words of Daly (1909, p. 100), “ a veritable resurrection of the Archean mountain-chain.” This re-elevation has given “ a distinct entity,” to use the phrase of Professor Daly (Jt. App. p. 2537), to the whole coastal belt of eastern Labrador.

C. TWO COASTAL TYPES

The second great contrast in Labrador is between the eastern and western shore lines. The Labrador shore in Hudson Bay extends in long even curves, although the curves may have many minor irregularities, and may be fringed with islets. The cliffs of Labrador along Hudson Bay, though bold in many places, are generally lower than those on the Atlantic coast, and the rivers are usually much longer than those that discharge to the Atlantic. The eastern coast, on the contrary, is intensely indented by inlets which

* Stanford's maps, 1891 and 1899, cf. Atlas No. 44, mark the coastal range as continuous from the western part of Kiglapait past Nain to the north side of Hamilton Inlet.

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run far inland ; the cliffs are precipitous, and the rivers, with one exception, are short.
Eastern Labrador consists of a belt of country very distinct in its geographical character from the country west of the watershed, and forms a geographical unit marked by three characteristics. First, this eastern belt is intersected by deep fiord valleys, many of which run for 20 to 40 or more miles inland, and have branch valleys which are also deep and have straight steep sides. The extension of the northern fiords across the coastal mountain belt was described by Koch in 1884 (Deut. Geogr. Blatt., VII. Pt. 2, 1884, pp. 151 – 163) as quoted by Packard (1891, p. 227).
Second, the land between these valleys consists of high isolated, steep-sided blocks. Professor Daly's photographs and descriptions show that these blocks rise to the same general level, and are parts of an ancient plateau which has been dismembered by the formation of the inlets and the land valleys continuous with the inlets. This feature is most typically shown in Northern Labrador, but the same structure occurs as far south as the Strait of Belle Isle ; it is shown by the wall-like front of the Mealy Mountains above the Hamilton Inlet, and by some of Professor Daly's photographs of the southern coast (e.g. Jt. App : fig. 33, p. 2555 at 55° N., fig. 35, p.2556 at 53° 14´, fig. 37, p. 2557) which show high lands rising abruptly from the plain along the shore.
Third, the possibilities of geographical development of the coast region are different from those of the country to the west. The development of the coastal region has been hampered by the difficulty of communication and transport, as the larger part of the surface is isolated by the deep intersecting fiords and fiord valleys. Throughout this belt communication is possible only by going to the coast along the inlets and fiord valleys ; traverse from north-west to south-east parallel to the coast is impracticable, owing to the height and steepness of the intervening mountains.

D. THE WATERSHED THE NATURAL BOUNDARY

The coastland is separated from the western moorlands by the watershed which for most of the peninsula is the natural separation. The watershed is the natural geographical division as it determines the direction of trade and commerce, since exports would go down the waterways to the sea.

II. THE ATLANTIC COAST AND ITS INLETS.

A. THE NORTHERN FIORDS

The eastern coastland is divided into two sections, the northern in which the arms of the sea are fiords, and the southern, in which as the level of the land is lower, the valleys are less deep and reach the sea as fiards. In the northern part the arms of the sea are typical fiords. In my book on Fiords

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FIG. I A— Outline of Nachvak Bay after Prof. Daly (1902, pl. 12). Scale, 6 miles to 1 inch.
FIG. I B— Nachvak Fiord as it would be if submerged to the contour 1,500 ft. of Daly. The dotted line shows the land as it would be if left by a submerence of 2,500 ft., with Nachvak converted into a fiard.


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FIG. 2— The entrance to the Sogne Fiord, Norway. The continuous line shows the present shore along the entrance to the fiord ; the dotted line shows the position of the shore as it would be with the submergence of 1500 feet, by which the fiord would be converted into a fiard. Scale, 1:100,000 from the Topographic Kart of Norway, Sheet 29B, 1915.


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(1913, pp. 281-2) I referred to Nachvak as a typical fiord. Professor Daly (1902, p. 230) describes it as “ an excellent type of fiord.” These northern arms of the sea are fiords because their sides are in general straight and parallel ; they bend at sharp angles ; they are often connected into a network by cross valleys which break the plateau into isolated blocks. At the northern end of the Peninsula some of these fiord valleys form narrow straits known as tickles, which extend from shore to shore ; and along the eastern coast the meeting of two fiord valleys often forms a tickle which cuts off part of the land as an island block. That the fiord valleys intersect a plateau is shown by Professor Daly's photographs, figs. 1, 7, 8, 9. 10 & 11 Jt. App. pp. 2539-44. Another fiord characteristic is that on the floors of the valleys there are deep basins which are often deepest inland, and are connected with the sea by a shallow passage over a slightly submerged threshold.
The fiord nature of the northern inlets is shown in the following photographs by Professor Daly— Jt. App. figs. 1, p. 2539 ; fig. 6, p. 2541; figs. 7 & 8, p. 2542 ; fig. 10, p. 2543 ; fig. 12, p. 2544 ; fig. 19, p. 2548.

B. THE SOUTHERN FIARDS.

On the southern part of the coast the inlets differ in shape as their shores are very sinuous. They belong to the category of Fiards, so named after their typical representatives on the Swedish Coast. Fiards agree with fiords in their general plan. Lines drawn along the middle of a group of fiards have a similar arrangement to corresponding lines in a system of fiords. Fiards like fiords occur in areas of hard rocks, have basins which are often deep at their landward end, and are separated from the outer sea by a threshold. They differ from fiords by their margins being very sinuous, with the land projecting into them in many peninsulas, which are often continued by islets, while the valleys that continue the bays inland often contain lakes. The essential difference between a fiord and a fiard is that in the fiard the water surface stands near the upper edge of the valley ; if a fiord is drowned, as the water level rises and reaches the upper edges, which have been worn by wind and rain and streams, the shore line becomes extremely sinuous. This fact may be illustrated by fig. 1 of Nachvak Bay, based on the map by Prof. Daly (1902, p. 112). Fig. la shows the parallel sides of the bay, which has the plan of a fiord as it is now: fig. lb show the shape that the inlet would have if the water level were raised to the contour of 1,500 ft. ; it would then be intermediate between a fiord and a fiard : submergence to the 2,500 ft. contour would reduce the land to the areas shown by the dotted line on fig. lb and Nachvak would be a fiard.
That the southern inlets of Labrador are often fiards is shown not only by the maps but by Professor Daly's photographs ; Jt. App., fig. 28 ; Ford Harbour, p. 2552 ; figs. 29 and 30, Hopedale, p. 2553 ; fig. 35, Sloop Harbour,


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