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45
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Glacial features of the west-central Canadian Shield
Project 730013
J.M. Aylsworth and W.W. Shilts
Terrain Sciences Division
Aylsworth, J.M. and Shilts, W.W., Glacial features of the west-central Canadian Shield;
Research, Part B, Geological Survey of Canada, Paper 05-18, p. 375-381, 1985.
& Current
Abstract
A small scale map of selected glacial features (eskers, related outwash and meltwater features,
rogen moraine, and drift-free areas) was compiled for approximately 650 000 km2 of the Canadian
Shield lying between 60° and 66" N and west of Hudson Bay. It combines data obtained by airphoto
interpretation of selected glacial sediment characteristics of 37 1:250 000 NTS map areas and
surficial geology mapping of 28 additional sheets. This map is presented along with preliminary
discussion of regional glacial sedimentation patterns.
A widespread, integrated system of trunk and tributary eskers suggests stagnation of the
Keewatin Ice Sheet while it still covered a large area. In addition, distribution of constructional
glacial landforms suggests that erodibility of bedrock and character of resulting sediment
significantly influenced the type and pattern of glacial sedimentation. This influence may ha've been
a s great a control on the nature and distribution of landforms a s glacier dynamics.
Les auteurs ont port6 sur une c a r t e B petite Bchelle des formes du relief glaciaire (eskers,
plaines alluviales e t autres elements form& par les eaux de fonte moraine de Rogen e t regions
d6pourvues de sediments glaciaires) qui couvrent environ 650 000 km 1 du Bouclier canadien, entre les
60e e t 66e degres de latitude nord, Itouest d e la baie dlHudson. 11s ont group6 des donnees obtenues
par photo-interprgtation de certaines caracteristiques des sediments glaciaires observees dans
37 regions ca~tographieesb 11250 000 e t par cartographie des formations en surface de 28 autres
regions. Les auteurs accompagnent la presentation de c e t t e c a r t e dlun expose preliminaire des
modeles de sedimentation glaciaire regionaux.
Ltexistence dtun reseau etendu e t int6gre dteskers principaux e t secondaires semble indiquer que
ltinlandsis du Keewatin a connu une phase stationnaire au moment oh il recouvrait encore une vaste
rkgion. En outre, dtapr8s la repartition des formes construites du relief glaciaire, il semble que la
facilite dt6rosion de la roche en place e t les caract6ristiques des sediments qui en ont result6e aient
profondement influ6 sur la nature e t la forme de la sedimentation glaciaire, au point, peut-&re, .de
contr6ler la nature e t la repartition des formes de relief .9 Itinstar d e la dynamique des glaciers.
Introduction
Preliminary results of a reconnaissance airphoto interpretation of selected glacial f e a t u r e s of much of t h e westcentral part of t h e Canadian Shield have been combined with
more detailed mapping carried out near Hudson Bay by t h e
authors and colleagues. The resulting m a p reveals distinctive
patterns of deposition and erosion t h a t may have considerable
significance in interpretation of t h e history and dynamics of
t h e western part of t h e Laurentide Ice Sheet.
In this paper w e present a preliminary small-scale m a p
(Fig. 45.1) and a limited discussion of t h e meaning of t h e
patterns of deposition and erosion t h a t i t reveals.
Background
Most of t h e study a r e a was mapped a t a general
reconnaissance level by Geological Survey of Canada
personnel in t h e l a t e 1950s and early 1960s (Fyles, 1955;
Lee, 1959; Craig, 1964, 1965).
These early maps w e r e
restricted t o depicting or symbolizing t h e most prominent
geomorphic features, such a s major esker ridges, and only
portray rogen moraine, sometimes t e r m e d ribbed moraine
(Cowan, 1968; Hughes, 1964), in a fraction of t h e a r e a
actually covered by it.
No a t t e m p t was made t o
differentiate drift-covered from drift-free areas.
These
works w e r e compiled onto t h e Glacial Map of Canada
(Prest et al., 1968).
Since t h e Glacial Map of Canada was published, more
detailed surficial geology maps (1:125 000 and 1:250 000)
have been produced for much of t h e District of Keewatin.
These maps, in published or unpublished f o r m , cover approximately 40% of t h e a r e a of t h e present mapping project. For
t h e remaining 60%, major glacial f e a t u r e s have been
compiled
from interpretation of
1:60 000 s c a l e air
photographs on 1:250 0 0 0 s c a l e maps under c o n t r a c t t o
Terrain Analysis and Mapping Services Ltd., Stittsville,
Ontario.
Information from t h e s e maps was plotted a t
1:l 000 000 and further generalized for presentation h e r e
(Fig. 45.1).
General distribution p a t t e r n
In Figure 45.1 i t is possible t o discern four zones of
sedimentation patterns t h a t a r e roughly concentric about t h e
Keewatin Ice Divide:
featureless or drumlinized or fluted till plains (see GSC
maps 7-1979; 8, 9-1980; 1-1984; 2, 5-1985).
Individual
drumlins may occur within rogen moraine trains and
individual large ridges may b e fluted. Where rogen moraine
is best developed, i t s distribution is l i t t l e influenced by
topography, occurring both in depressions and on uplands, but
where t h e belts b e c o m e more widely s e p a r a t e d , down i c e
from t h e i c e divide, rogen moraine generally occurs
preferentially in depressions.
Distribution of rogen moraine about t h e Keewatin Ice
Divide is not uniform. It is r a r e west of Dubawnt Lake and
e a s t of Baker Lake (indicated by ? on inset map, Fig. 45.1)
where large a r e a s a r e devoid of glacial deposits or a r e
covered by a featureless till veneer, and northwest of
Dubawnt Lake where a n extensive drumlin field occurs. The
northern boundary of t h e southwestern-most field of rogen
moraine is remarkably distinct against t h e featureless till
plain west of Dubawnt Lake. In general t h e down-ice margin
of t h e zone of rogen moraine is abrupt although isolated,
small, linear trains occur in t h e inner half of t h e next zone.
Eskers also begin near t h e boundary between Zone 1 and
Zone 2 and, like t h e rogen moraine trains, r a d i a t e from t h e
region of t h e Keewatin I c e Divide. A typical esker system
begins a s a series of hummocks or short s e g m e n t s which pass
downstream into continuous large eskers joined by a r e a s of
outwash or m e l t w a t e r channels. Along a section measured
across t h e southwestern part of Zone 2, eskers a r e spaced
approximately 1 3 km a p a r t , with spacing varying from 2 t o
27 km. Throughout most of t h e a r e a eskers a r e sharp ridged,
u p t o 40 m high, with occasional conical knobs projecting well
above t h e a v e r a g e elevation of t h e esker crest. Along their
length they m a y b e periodically interrupted by bulges w h e r e
t h e single ridge splits into multiple ridges which coalesce
downstream. Above marine limit t h e y a r e commonly flanked
by outwash in t e r r a c e s disrupted by k e t t l e lakes. North of
Thelon River eskers a r e associated with prominent outwash
t e r r a c e s and t h e tops of t h e eskers a r e in s o m e places f l a t ,
planed off by m e l t w a t e r flowing on a s t a g n a n t i c e floor into
which t h e esker ridge w a s frozen (Shilts, 1984).
Below marine limit, eskers a r e commonly reworked by
wave action in t h e o f f l a p phase of t h e Tyrrell Sea. This has
had t h e e f f e c t of subduing t h e i r relief t o t h e e x t e n t t h a t t h e y
rarely project m o r e t h a n 1 0 m above t h e adjacent terrain.
Sonar profiles show t h e m t o retain t h e i r relief and sharp
c r e s t w h e r e t h e y a r e submerged in d e e p lakes (W.W. Shilts,
unpublished data).
Zone I
The innermost zone, characterized by t h e absence of
eskers and rogen moraine (Lundqvist, 1969) occupies southern
Keewatin and extends about 5 0 km on either side of t h e
Keewatin Ice Divide (Lee et al., 1957). The c h a r a c t e r i s t i c
landscape of Zone I comprises till plains with a r e a s of low
till hummocks and virtually no oriented depositional features.
It is almost completely devoid of glaciofluvial deposits,
except for minor outwash in s o m e valleys. The location of
t h e i c e divide (Fig. 45.2), which forms t h e axis of t h e region,
is clearly defined by striation orientations.
Zone 2
Zone 2 is 200-250 km wide, surrounds Zone 1 on t h r e e
sides, and is characterized by t h e presence of well developed
rogen moraine and esker-outwash systems.
Rogen moraine comprises sinuous ridges trending
roughly perpendicular t o i c e flow (Cowan, 1968; Shilts, 1977)
and occurs in linear belts or trains parallel t o major
directions of i c e movement. The trains of rogen ridges
r a d i a t e from t h e Keewatin Ice Divide like t h e spokes of a
wheel.
In t h e a r e a s between rogen trains, drift forms
Zone 3
Zone 3, which lies west of Zone 2, is characterized by
a n i n t r i c a t e dendritic p a t t e r n of eskers, and continuous d r i f t
cover.
It f o r m s a 2 0 0 t o 300 km-wide belt of glacial
sediment, commonly till, which thins t o a discontinuous
veneer in t h e outer p a r t of t h e zone. L a r g e esker systems
a r e known t o extend into Hudson Bay and wave-reworked
eskers, bearing e r r a t i c s common t o t h e Keewatin mainland,
occur within t h e Bay o n C o a t s Island (Shilts, 19.82), suggesting
t h a t a n a r e a similar t o Zone 3 may l i e east of Zone 2,
submerged by Hudson Bay.
Within Zone 3 rogen moraine occurs only as isolated,
short, narrow, linear trains, lying in depressions and closely
associated, in space, if not in t i m e or genesis, with eskers.
Within t h e rogen a r e a s , individual ridges a r e much smaller
and depart considerably in shape f r o m t h e "classical" rogen
moraine (Lundqvist, 1969) of Zone 2 (S. Paradis, personal
communication, 1985).
Compared t o t h e 1 3 km spacing of eskers in Zone 2,
spacing between eskers decreases t o approximately 8 km
(3-15 km range) 200 km downstream (southwest) from t h e
----------
Esker (segment : continuous)
"
Rogen mora ine
WO
Scale
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Drift- f ree zone ( ,80% bedrock outcrop)
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Figure 45.1 •
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Distribution of selected glacial features on the west-centr al Canadian Shield.
---- ---
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probable ice recessional position
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extent
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Figure 45.2.
Glacial geology features discussed in the text.
section t h a t was measured in Zone 2. Although numbers of
eskers and their tributaries increase in Zone 3, the overall
size (height and width) decreases in this zone.
In t h e outer part of Zone 3 t h e esker systems become
more discontinuous and disorganized, and esker distributaries
a r e common. Short esker segments a r e commonly oriented in
various directions and areas of crevasse -fillings a r e
associated with disruption of t h e esker system.
Within t h e northwestern portion of this zone a
prominent ice recessional position (Fig. 45.2) is marked by a
chain of ice-contact deltas or fans, other outwash features,
and esker distributaries which extends parallel t o and north
of t h e Back River. In t h e vicinity of this feature, short
parallel esker segments abound between t h e major systems.
Zone 4
The outermost zone of t h e Canadian Shield part of t h e
study region is characterized by extensive bedrock outcrops
t h a t a r e nearly bare of drift. Although t h e transition from
Zone 3 t o 4 is abrupt in t h e southern part of t h e study area,
long trains of drift project into major lowlands along t h e
northern part of t h e boundary. The abrupt transition from
drift t o no drift in t h e south parallels 11O0 longitude and then
curves northeastward south of t h e Eastern Arm of Great
Slave Lake. It corresponds roughly t o t h e eastern boundary
of t h e Fort Smith Belt, a northward-trending zone of
radioactive gneisses and intrusive rocks (Charbonneau, 1980;
Fig. 45.3). The transition zone north of Great Slave Lake
corresponds with t h e eastern edge of t h e Beartslave
Structural Province (Fig. 45.3). The long trains of relatively
continuous drift cover that extend northwestward along
lowlands developed in t h e crystalline bedrock of t h e
Beartslave province, a r e probably-trains of debris eroded and
transported from t h e poorly consolidated sedimentary rocks
of Thelon Basin (Fig. 45.3).
Esker pattern
The eskers radiating outwards from t h e Keewatin Ice
Divide consist of networks df tributaries which form
dendritic patterns similar t o a simplified Horton system.
These esker systems can be traced as f a r a s 600 km and
continuous lengths of individual eskers can be traced for up
t o 75 km. In many places, discontinuous segments a r e linked
by meltwater channels, usually scoured through drift t o
bedrock or filled by outwash.
Tributary eskers join t h e main esker preferentially from
t h e left; that is, from t h e north on those eskers deposited by
eastward-flowing meltwater east of t h e Keewatin Ice Divide
and from t h e south on those eskers deposited by westwardflowing meltwater west of t h e divide (Fig. 45.1).
This
observation is best illustrated by t h e esker system trending
northwestward from Dubawnt Lake where, in a distance of
300 km, 9 tributaries join from t h e south and none from t h e
north. Similarly, between its origin near Yathkyed and Henik
lakes and Hudson Bay most tributaries of t h e Maguse River
esker system join t h e trunk stream on its north side. In most
cases t h e orientation of t h e tributary esker changes abruptly
a s i t approaches t h e main esker and t h e tributary joins t h e
main esker a t right angles.
1 1 2 0 1100
66%----~------
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w e s t e r n limit of C a n a d i a n S h i e l d
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Group: s e d i m e n t a r y 8 volcanic r o c k s
Figure 45.3.
Bedrock geology features discussed in the text.
In some locations clusters of short, parallel esker ridges
occur between trunk eskers, and distributary ridges fan out
from trunk eskers. One such cluster occurs along t h e coast
south of Chesterfield Inlet. There a r e several areas with
similar clusters in eastern Keewatin and somewhat similar
features, although more disorganized and associated with
crevasse fillings, occur near t h e western edge of Zone 3. The
eastern clusters may mark t h e position of t h e i c e front during
slowing of glacier melt-back and thus may correlate with
similar positions northwest of t h e Keewatin Ice Divide
(see above, Zone 3) (Fig. 45.2).
Implication of patterns
Even a t t h e reduced scale of these figures. t h e
resolution of major geomorphic features is c&siderably
enhanced over t h e only previous compilation, t h e Glacial Map
The following a r e only
of Canada (Prest et all, 1968).
preliminary comments based on an initial analysis of d a t a
currently on hand.
Esker systems
In an earlier paper, Shilts (1984, p. 218) described in
some detail t h e characteristics of a typical esker of t h e
western Canadian Shield; esker systems were described as
reflecting
'I...
what appears t o have been a fully integrated
Horton system of tributaries and trunk streams,
regularly bifurcating upstream into lower order
tributaries until t h e deposits disappear near t h e
Keewatin Ice Divide.
This pattern may be
interpreted in at least three ways: I) The whole
system may have functioned subglacially in sub-ice
tunnels extending from t h e c e n t r e of a thin,
stagnant glacier t o its retreating margins, which lay
at one t i m e some 300-500 km away. Although this
model has some merit, t h e very size of t h e i c e sheet
a t t h e inception of esker deposition would seem t o
argue against it, t h e thicker ice near t h e divide
being too plastic a t t h e base t o maintain open
tunnels. In addition, i t is hard t o image how t h e
Horton system could have developed s o fully within
a solid mass of ice; topographic irregularities a t t h e
base of t h e ice would have exercised greater
influence on esker trends than is evident from t h e
Horton pattern.
2) The esker may have been
deposited by streams flowing in short tunnels near
t h e margin of t h e glacier, continuity being
maintained by up-ice migration of t h e heads of t h e
tunnels by melting (St-Onge, 1984, p. 274).
Although this model is more compatible with
observed sedimentation features and probable
dynamic conditions in t h e retreating ice, it does not
explain well t h e Horton pattern of tributaries. It is
hard t o imagine how a subglacial tunnel would
bifurcate regularly a s i t melted up i c e without some
external control. 3) The most attractive model of
glacial meltwater drainage in this region is
presently one in which an integrated system of
drainage channels developed on t h e surface of t h e
glacier, t h e meltwater plunging t o t h e base of t h e
glacier t o flow in a subglacial tunnel t h e last few
kilometres of its course before issuing from t h e
retreating glacier front (similar t o t h e model
suggested by St-Onge, 1984, p. 273). This system
would have developed quite l a t e in t h e glacial cycle,
when most of t h e glacier was below t h e equilibrium
line. The tunnels near t h e ice edge would have
extended themselves headward by melting, as in t h e
preceding model, but their headward migration
would have followed roughly t h e traces of t h e
surface drainage, thus accounting for t h e regular
bifurcation uostream. ' This hvbrid model best
explains both 'the Horton drainagk pattern and t h e
manifest evidence of subglacial origin of esker
sediments."
The dendritic pattern of t h e eskers provides t h e most
compelling evidence of t h e stagnant nature of t h e ice sheet.
It is difficult t o conceive of a dendritic meltwater system
developing and maintaining itself on the surface of an active
ice sheet; it is similarly difficult t o conceive of tributary
eskers joining t h e main esker a t right angles within
vigourously moving ice.
The reason for t h e preferred
direction of approach of tributaries (from t h e left) is
unknown. Perhaps i t reflects t h e influence of Coriolis force
on t h e movement of water on a large featureless plain - t h e
surface of t h e ice sheet (a hypothesis t h a t requires most of
t h e i c e cover over t h e area of this study t o be below t h e
equilibrium line).
Disruptions in t h e esker pattern a r e thought t o indicate
temporary halts in t h e retreat of t h e ice front, possibly t h e
result of climate deterioration. The most prominent of these
zones lies in an a r c north of Back River (Fig. 45.2) and is
accompanied by an extensive outwash complex. When areas
of numerous disorganized short esker segments, crevasse
fillings, and esker distributaries, which occur in t h e outer
portion of Zone 3, a r e linked, they seem t o extend this
marginal position in a single a r c across t h e western part of
t h e study area. Clusters of esker distributaries and short
parallel esker segments in eastern Keewatin may also record
positions of temporary halts of t h e ice front. The most
prominent of them may be contemporaneous with t h e western
position, t h e rapid retreat of t h e ice which fronted t h e more
than 150 m deep water of t h e Tyrrell Sea, accounting for t h e
asymmetry of their locations with respect t o t h e ice divide.
The height and width of an esker ridge is roughly
proportional t o t h e amount of debris supplied- t o its conduit
while i t is flowing near or a t t h e base of a glacier. Assuming
t h a t basal conduit length and duration of meltwater flow a r e
similar for most eskers in this region, t h e diminishing size of
t h e eskers with distance from t h e ice divide may reflect a
regularly decreasing amount of basal debris in t h e glacier.
'Particularly in Zone 4, t h e small size and low frequency of
eskers and the paucity of drift suggest that t h e ice was
relatively clean. This implies 1) t h a t there was little erosion
of t h e generally hard crystalline bedrock of Zone 4 and 2)
t h a t most debris carried by ice through t h e region was
derived from t h e inner zones and was mostly deposited before
reaching Zone 4.
If t h e assumption that t h e well developed dendritic
esker systems developed in stagnant ice is correct, then t h e
stagnant ice sheet would have covered zones 2 and 3. Ice
over Zone I may have remained active while t h e outer zones
were stagnant, although eventually it too would have become
stagnant, thinning until only remnant i c e blocks remained in
lake basins. The absence of well developed, dendritic, esker
systems over southern and western parts of Zone 4 may
indicate t h a t retreat of t h e ice sheet within this area was
accomplished by back melting of active ice, but,
alternatively, may only reflect t h e paucity of basal debris in
stagnant ice.
Much of t h e northern portion of Zone 4
contains well developed dendritic esker systems. The reason
t h a t eskers were developed in t h e northern part of Zone 4
may be that dispersal trains of debris from t h e east
penetrated along t h e lowlands and provided sediment t o t h e
meltwater streams in this area. To t h e south, a lack of
debris in t h e i c e may have prevented t h e development of
esker ridges. A third alternative suggested t o t h e authors is
that t h e lack of eskers in Zone 4 may be related t o retreat of
t h e ice front in a proglacial lake. This does not seem t o be
likely because eskers a r e well developed below marine limit
east of t h e ice divide, and they occur both below and above
lacustrine limits west of t h e divide (Fig. 45.2).
Rogen moraine
Rogen moraine is confined t o a well defined belt around
t h e Keewatin Ice Divide. Thus, distribution of fields of rogen
moraine appears t o be directly related t o t h e position of t h e
ice divide, and, therefore, t o t h e glacier dynamics in t h e
region adjacent t o t h e ice divide.
In Sweden,
Lundqvist (19691, observed that rogen moraine occurred only
above marine limit and then only in valleys or other
depressions. In contrast, on t h e western Canadian Shield
rogen moraine occurs with equal frequency above and below
marine limit, and where best developed, is found both in
depressions
and on topographically positive areas.
Furthermore, both rogen moraine and drumlins or flutings
occur in long, narrow trains radiating in t h e direction of ice
flow outward from t h e region of t h e ice divide.
The
two types of landform trains pass laterally one into t h e other,
and individual trains commonly can be traced back t o specific
outcrops of particular bedrock lithologies (Shilts, 1977) or
specific areas of coarse unconsolidated sediments.
In general, rogen moraine is composed of coarse,
bouldery o r gravelly debris t h a t is relatively undeformable,
even when saturated. Conversely, a t t h e few sites checked in
eastern Keewatin, trains of drumlins or flutings appear t o be
underlain by more clay- and silt-rich drift that deforms
readily when saturated. It is possible that t h e dynamic
conditions in glacier ice near t h e ice divide were such that
either drumlins or rogen moraine could be formed where a
sufficient subglacial thickness or basal load of debris was
available. Because of t h e lateral alternation of one feature
with t h e other, and their compositional peculiarities, i t is
possible t h a t wherever t h e basal debris load reached a
sufficient amount, trains of either drumlins or ribbed moraine
formed, with t h e type of feature formed dependent largely on
t h e local physical characteristics of t h e debris.
The reason for t h e abrupt down-ice termination of t h e
rogen patterns is not known. Drumlins a r e most abundant in
Zone 2 but continue t o occur through Zone 3; rogen moraine,
on t h e other hand, is concentrated in Zone 2 and occurs only
sporadically and in depressions in t h e other zones.
Drift cover
The lack of drift and apparent lack of erosion within
Zone 4 may reflect t h e resistant nature of t h e underlying
bedrock, t h e dynamics of t h e ice, or a combination of both.
A prolific source of debris is available in t h e easily eroded
sedimentary rocks of t h e Thelon Basin. This debris, however,
was largely depleted before t h e ice passed from Zone 3.
Possibly t h e crystalline rock t h a t underlies t h e Beartslave
Province and Fort Smith Belt was largely resistant t o erosion
and s o did not yield much autocthonous debris. Although t h e
absence of drift in Zone 4 probably reflects t h e resistant
nature of t h e underlying bedrock, i t is possible t h a t ice
dynamics may have been influenced by local topography,
particularly south of Great Slave Lake where t h e relief is
rugged and t h e trend of valleys is perpendicular t o t h e
direction of movement of ice. As t h e elevation of this area
is 300 m higher than t h a t a t t h e c e n t r e of t h e ice sheet and
isostatic depression a t the time would have accentuated this
difference, the ice sheet may have been thin enough over this
a r e a t o b e frozen t o its bed, preventing erosion. Another
possible explanation of t h e lack of evidence of erosion is t h a t
i c e within t h e valleys oriented transverse to the direction of
ice movement, may have been largely stationary so t h a t most
regional ice flow occurred above the base of t h e i c e sheet. If
this was t h e case, little erosion could have occurred.
Conclusions
1. The pattern of esker distribution described herein strongly
suggests t h a t t h e last stages of Wisconsin Glaciation west
of Hudson Bay consisted of the backwasting of a large,
thin, stagnant ice sheet centred on t h e District of
Keewatin. The diameter of this relatively dormant ice
mass may have exceeded 1500 km.
2. The pattern of rogen moraine distribution is primarily
associated with t h e configuration of t h e Keewatin Ice
Divide.
The trains of rogen moraine and associated
drumlins that radiate from the ice divide region a r e also
associated with areas of outcrop of specific bedrock
lithologies or unconsolidated sediment, suggesting t h a t
t h e erodibility of the substrate and characteristics of the
eroded material in transport have a strong influence on
t h e nature and distribution of resulting landforms.
3. Large areas where drift cover is thin or absent may b e
resistant t o glacial erosion and may also b e located
beyond the zone of deposition of easily entrained bedrock
debris (principally in t h e Thelon Basin) which lies near or
on the Keewatin Ice Divide.
4. Finally, although t h e regional patterns of drift deposition
and landform development may be related t o some extent
t o regional dynamic conditions a t t h e base of t h e
Keewatin ice sheet when i t was actively flowing, there is
little doubt that t h e lithology and topography of outcrops
over which the glacier passed exerted an important
influence on i t s deposits.
References
Charbonneau, B.W.
1980: The Fort Smith radioactive belt, Northwest
Territories;
Current Research, P a r t C,
Geological Survey of Canada, Paper 80-LC,
p. 45-47.
Cowan, W.R.
1968: Ribbed moraine: Till-fabric analysis and origin;
Canadian Journal of Earth Science, v. 5,
p. 1145-1159.
Craig, B.G.
1964: Surficial geology of east-central District of
Mackenzie, Geological Survey of Canada,
Bulletin 99, 41 p.
1965: Glacial Lake McConnell, and t h e surficial geology
of parts of Slave River and Redstone River mapareas, District of Mackenzie; Geological Survey
of Canada, Bulletin 122, 33 p.
Fyles, 3.G.
1955: Pleistocene features;
Geological notes on
central District
of
Keewatin,
Northwest
Territories by G.M. Wright; Geological Survey of
Canada, Paper 55-17, p. 3-4.
Hughes, O.L.
1964: Surficial geology, ~ i c h i c u n - ~ a n i a ~ i s k amapu
area, Quebec; Geological Survey of Canada,
Bulletin 106, 20 p.
Lee, H.A.
1959: Surficial geology of southern District of Keewatin
and t h e . Keewatin Ice Divide, Northwest
Territories; Geological Survey of Canada,
Bulletin 51, 42 p.
Lee, H.A., Craig, B.G., and ~ ~ l e3.G.
s ,
1957: Keewatin Ice Divide; Geological Society of
America
Bulletin,
v.68,
no.12,
pt.2,
p. 1760-1761 (abstract).
Lundqvist, 3.
1969: Problems of the so-called Rogen moraine;
Sveriges geologiska undersokning, Ser C NR 648
(Arsbok 64 NR 51, 32 p.
Prest, V.K., Grant, D.G., and Rampton, V.N.
1968: Glacial Map of Canada; Geological Survey of
Canada, Map 1253A, 1:5 000 000 scale.
St-Onge, D.A.
1984: Surficial deposits of the Redrock Lake area,
District of Mackenzie; & Current Research,
PartA,
Geological
Survey
of
Canada,
Paper 84-IA, p. 271-277.
Shilts, W.W.
1977: Geochemistry of till in perennially frozen terrain
of
the
Canadian
Shield - application
to
prospecting; Boreas, 6, p. 203-212.
1982: Quaternary evolution of t h e Hudson/James Bay
Region; Naturaliste Canadien, v. 109, p. 309-332.
1984: Esker sedimentation models, Deep Rose Lake
map-area, District of Keewatin; & Current
Research, P a r t B, 'Geological Survey of Canada,
Paper 84-lB, p. 217-222.
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Folding in t h e Neruokpuk F o r m a t i o n along t h e F i r t h River.
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