A Pleistocene Clastic Dike, Upper Chaudikre Valley, Qukbec
JEAN-CLAUDE
DIONNE
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
Laurentian Forest Research Centre, Canadian Forestry Service, Department of the Environment, 1080 Route du Vallon,
Ste-Foy, Que'bec GI V 4C7
AND
W. W. SHILTS
Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario KIA OE4
At St. Ludger, Upper Chaudiere Valley, in southern Qutbec, glacio-lacustrine sands of the
Gayhurst formation which are older than 20 000 years B.P., are cut by a vertical till dike, 40 cm
in width and more than 200 cm in height. The infilling materials are similar to those of the overlying Lennoxville till. The trend of the dike is at right angles to the major direction of flow of the
last glacier. It is believed that infilling from above occurred when the Laurentides ice sheet
overrode and fractured the underlying sands during the Wisconsin stage.
A Saint-Ludger, dans la haute vallte de la Chaudikre, au Quebec mkridional, les sables glaciolacustres de Gayhurst datant de plus de 20 000 ans A.A. sont traverses par un filon de till vertical
de 40 cm de largeur et plus de 200 cm de hauteur. Les materiaux de remplissage Btant identiques
a ceux du dill de Lennoxville sus-jacent suggerent une mise en place par le haut dans une fissure
produite dans des sables lorsqu'ils furent recouverts par I'inlandsis laurentidien au cours du
Wisconsin. La direction du dike est a angle droit avec la direction principale du dernier glacier.
Introduction
Clastic dikes commonly occur in consolidated
sedimentary rocks. They have been reported and
discussed by numerous authors for more than
150 years (Strangways 1821, p. 386, 407-408).
Various kinds of clastic dikes are found in sedimentary rocks of various ages around the world,
and they often occur in flysch sequences (Pruvost
1943; Gottis 1953; Dzulynski and Radomski
1956; Colacicchi 1959; Hayashi 1966; Andrieux
1967; Teisseyre 1967), and in rocks deposited in
a geosynclinal environment (Fairbridge 1946;
Smith and Rast 1958; Marinov 1971). They form
in various ways and their significance is not
always well understood (Rutten and Schonberger
1957; Hayashi 1966; Marschalko 1972). However, occurrence of clastic dikes in unconsolidated Quaternary deposits is poorly documented
except for ice-wedge casts which develop in
perennially frozen deposits (Johnsson 1959;
Dylik and Maarleveld 1967). In order to avoid
length and confusion, this well-known type will
not be discussed. There are few reports of other
kinds of dikes in unconsolidated deposits
(Oldham and Mallet 1872; Whitten 1898;
Jenkins 1925a; Monroe 1932; Lupher 1944;
Moret 1945; Schwarzbach 1952; Kaiser 1958;
Reimnitz and Marshall 1965; Oomkens 1966;
Heron et al. 1971).
Till dikes are a type of clastic dike thought to
Can. J. Earth Sci., 11.1594-1605 (1974)
be a reliable indicator of ice flow direction
(Dreimanis 1969). The purpose of this paper is
to report and discuss the significance of a vertical
till dike occurring in a Pleistocene deposit in
southern Quebec (Dionne 1971).
Terminology
In order to avoid confusion, a few words on
terminology are suitable. Clastic dike is a general
expression for any wedge-shaped feature, usually
in a vertical or in a nearly vertical position, filled
with clastic materials, and cutting through different layered consolidated or unconsolidated
sedimentary rocks. Clay, silt, sand, gravel, and
till dikes are all clastic dikes. The expression
clastic wedge is often used as an equivalent of
clastic dike (Dzulynski 1965). Unfortunately this
expression was given an entirely different
meaning by Pettijohn (1957) and others (King
1959; Teisseyre 1967; De Jong 1971). Gary el al.
(1972, p. 129) defined a "clastic wedge" as "the
sediments of an exogeosyncline derived from the
tectonic land masses of the adjoining orthogeosynclinal belt." Consequently the use of the
expression clastic wedge as a synonym for
clastic dike should be avoided.
Dreimanis (1969) introduced the expression
till wedge for wedge-shaped vertical or nearly
vertical structures, corresponding to downward
intrusion of till from the base of a glacier into
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
DIONNE AND SHILTS: CLASTIC DIKE
friction cracks formed in the underlying frozen
sand. The same meaning is given this term by
Morner (1972, 1973), but it is criticized by
Worsley (1973). In this paper the expression
till dike seems more appropriate for a vertical
feature not exactly identical to till wedges
formerly described.
1595
(uplift); (7) by glacial pressures, when a glacier
overrides frozen sediments or unconsolidated
sediments with some tensile strength.
Filling of cracks, fissures or other such features
results from clastic materials introduced into
cracks from above or from below. Infilling from
above usually results from gravity, free particles
falling into open cracks; this is the mode of
formation of ice-wedge casts and periglacial sand
Origin of Clastic Dikes
wedges (Butrym et al. 1964). Clastic materials
Clastic dikes in unconsolidated sediments and may be also forced downward by load pressures
in consolidated rocks form in various ways in deposits with reverse density gradients (Selly
(Tables 1 and 2). According to Hayashi (1966), and Shearman 1962; Dzulynski 1965; Anketell
a classification by genesis will include the fol- et al. 1970), or by pressures such as those
lowing categories: (1) intrusive clastic dikes, exerted by an overriding glacier, an iceberg or an
when clastic materials are forced upwards into ice floe. Filling from below always results from
fissures or cracks in connection with igneous or underground pressures, clastic materials being
volcanic activity; (2) injection clastic dikes, when injected upwards under hydrostatic pressures
liquefied clastic materials are injected into cracks, from water-saturated sediments which have been
fissures or joints under hydrostatic pressure liquefied, or by expulsion of air and gas.
(from below) or load pressure (from above); (3)
infilling clastic dikes, when clastic materials
Previous Observations on Clastic Dikes in
accumulate into open cracks, joints and other
Unconsolidated Deposits
such structures under the influence of gravity;
Till dikes or till wedges have previously been
(4) squeezed-in clastic dikes, when unconsolidescribed
from southern Ontario (Dreimanis
dated or semiconsolidated plastic layers are
1969;
verbatim
1973'), Nova Scotia (Morner
squeezed, under stress, into cracks or fissures in
1973),
western
Connecticut (Schafer 1969),
the adjacent rocks below or above without
Scotland
(Anderson
1940), and Sweden (Lunddestroying their internal structures ; (5) diagenetic
qvist
1967
p.
55;
Morner
1972). However, only
clastic dikes, when primary clastic dikes are
altered owing to diagenetic modifications; for Dreimanis and Morner have discussed the signiexample, a sandstone dike may become a ficance of till wedges as a reliable indicator of
siliceous or chalcedony dike under diagenetic paleo ice-flow direction.
The first reference to till dikes is probably that
processes.
Generally two things must be considered in by Whitten (1 898) who described "clay dikes" in
the formation of any clastic dikes: first the sand from South Bend, Indiana. Dikes were 10
formation of fissures or cracks, and second their to 30 cm in width by 100 to 250 cm in depth,
filling. In most cases, particularly in uncon- were nearly vertical in the upper part and all
solidated sediments, opening of fissures and curved to the north or up-stream. They resulted
their filling are contemporaneous or simul- from the filling by clay of cracks in frozen sands
taneous; in consolidated rocks a long lapse of when overridden by ice: "... the sand with its
time may have occurred before filling of cracks. open fissures was overridden by ice, the base of
Fissures and cracks are produced in various which transported or shoved the clay over the
ways: (1) by contraction under frost action or sand, rubbing off particles of clay and sand to fall
under drying (desiccation); (2) by mass move- to the bottom of the crevices until the dikes
ment including slumping, landsliding and soli- were formed" (Whitten 1898, p. 239).
Till dikes in an underlying crystalline bedrock
fluction; (3) by subsidence as a consequence of
have
been reported from New Hampshire
compaction and dewatering of underlying sedi(Goldthwait
and Kruger 1938; Kruger 1938),
ments, or overloading in deposits with reverse
Rhode
Island
(Birman 1952), and have been
density gradients; (4) by collapsing following
underground dissolution of calcareous strata or
'In a letter dated March 16, 1973, Dr. Dreimanis indimining activity; (5) by seismic activity (earth- cated to J. C. Dionne that he was working on a paper on
quakes); (6) by faulting related to orogenesis till wedges observed in southern Ontario.
C A N . J . EARTH SCI. VOL. 11, 1974
TABLE
1. Clastic dikes in consolidated rocks'
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
Authors
Features
Andrieux 1967
Sandstone dikes
Campbell 1904
Conglomerate dikes
Case 1895
Mud and sandstone dikes
Cross 1894
Sandstone dikes
Diller 1890
Sandstone dikes
Dzulynski and Walton 1965
Siltstone and sandstone dikes
Eldridge 1906
Gilbert 1880
Gottis 1953
Asphalt veins
Sandstone dikes
Sandstone dikes
Grabau 1900
Sandstone dikes
Gresley 1898
Clay veins
Hay 1892
Sandstone dikes
Hayashi 1966
Irving 1883
Conglomerate and sandstone
dikes
Sandstone dikes
Lambrecht and Thorez 1966
Sandstone dikes
Lawler 1923
Sandstone dikes
McCallie 1903
Sandstone dikes
Newsom 1903
Sandstone dikes
Parker 1933
Sandstone dikes
Pavlow 1896
Sandstone dikes
Peterson 1968
Powell 1969
Sandstone dikes
Sandstone dikes
Pruvost 1943
Sandstone dikes
Rutten and Schonberger 1957
Sandstone dikes
Smith 1952
Sandstone dikes
Smith and Rast 1958
Sandstone and brecciated dikes
Origin
Upward and downward injections into
fissures caused by earthquake and
slumping.
Upward injection of material into open
fissures under strong hydrostatic pressure.
Injection from below by hydrostatic
pressures into desiccation cracks and
fissures formed by segregation of the clays
around local centers.
Injection from above into fissures in a
crystalline bedrock.
Injection from below into fissures caused by
earthquake.
Downward injections due to load, slumping
or earthquake.
Filling from above of contraction cracks.
Filling from above of contraction cracks.
Filling of fissures caused by compaction or
seismic movements.
Injection from above into fissures caused by
earthquake.
Injection from below into fissures caused by
earthquake.
Injection from below into fissures caused by
orogenic movement.
Various origins.
Filling from above of fissures in an
underlying crystalline bedrock.
Upward injections related to overloading
silt possibly in connection with
earthquake activity.
Filling from above of contraction
(desiccation) cracks.
Filling of fissures caused by earthquake or
landsliding.
Injection from below by hydrostatic
pressures into fissures probably caused
by orogenic movements.
Injection from below of water-saturated
sands into faults and fissures caused by
orogenic movements.
Injection from below into fissures caused by
earthquake.
Injection from below. ....
Upward and downward intrusion accompanying tectonic dewatering.
Filling from above of fissures caused by
differential subsidence.
Filling from above of tension cracks caused
by slumping.
Filling from above of fractures resulting
from minor local deformation
(possible warping).
Downward injection contemporaneous with
slumping and upward injection later than
slumping into fissures probably produced
by seismic activity.
1597
DIONNE AND SHILTS: CLASTIC DIKE
TABLE
1. (Concluded)
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
Authors
Features
Smyers and Peterson 1971
Stewart 1911
Sandstone dikes
Conglomerate dikes
Vintanage 1954
Sandstone dikes
Williams 1927
Sandstone dikes
Young 1972
Brecciated dikes
Origin
Upward injection of sand into fractures.
Joints enlarged by weathering and filled in
part by the product of this weathering
and in part by sediment washed in by
stream.
Filling from above of fissures caused by
submarine faulting.
Injection from below into fissures caused
by differential uplift possibly accompanied
by earthquake shocks.
Injection from above into fissures caused by
a secondary pressure lowering.
'This table is not an exhaustive review of reports on clastic dikes.
observed by Shilts in southern Vermont. They
correspond to filling by till of previous fissures
in the bedrock and are then not equivalent to
true till wedges or till dikes in unconsolidated
sediments. They can neither serve as an ice-flow
indicator nor as an indicator of former occurrence of permafrost.
Because of their characteristics the clastic
dikes from eastern Washington reported by
Jenkins (1925~)and considered as fillings of
cracks resulting from earthquake disturbances,
are probably ice-wedge casts or sand wedges
(PCwC 1959). The "clay dikes" reported by
Monroe (1932) from Mississippi and the "gravel
dikes" from France reported by Moret (1945)
are related to landsliding and upward injection
of clay or gravel from below. The clay, silt, sand
and gravel dikes of the Columbia Basin region,
Washington and Idaho, reported by Lupher
(1944) are probably the more abundant, varied
and complex clastic dikes known in Pleistocene
lake and stream deposits. Most dikes are considered as the filling from above of fissures
resulting from melting of buried ice, filling being
the result of lake and stream currents that moved
across open fissures and deposited dike sediments. A few dikes are landslide fissures filled
from above, and others are related to underground streams. The recent sand dikes described
by Reimnitz and Marshall (1965) from Alaska
resulted from quick sand injected upward into
overlying fissured beds during a 1964 earthquake.
Those reported by Oldham and Mallet (1872)
from India have a similar origin. The small sand
dikes described by Oomkens (1966) from a
desert basin in southwestern Libya are considered as injections from below into desiccation
cracks and also as eolian fillings from above.
The two wedge-cast structures reported by
Dionne (1970) from the Saguenay Region,
QuCbec, are considered as glacitectonic features
rather than true clastic dikes even though they
are vertical features cutting through enclosing
sediments. Heron et al. (1971) reported on
numerous sandy-mud clastic dike's in poorly
consolidated silty and clayey sand, in North and
South Carolina Coastal Plain. Dikes range from
2 to 60 cm in width, up to 150 cm in depth, and
up to 22 m in length. They "formed through
filling of fractures of soil material that developed
in the upper B horizon. Most fractures probably
developed in weathered rock as a result of slump
or hillside creep" (Heron et al. 1971, p. 1808).
Geographical and Geological Setting
The till dike was discovered in 1969 in a borrow pit beside old Provincial Route 24, on the
west side of St. Ludger, QuCbec, half way
between St-Georges-de-Beauce and Lac-MCgantic (Fig. 1). The area is underlaid by sedimentary
Paleozoic rocks of the Appalachian Province,
mantled by Quaternary unconsolidated deposits
which are usually thick in depressions and thin
on plateaus and hillsides. Shilts (1969) has
mapped the Quaternary deposits of the area, and
McDonald and Shilts (1971) have described the
local glacial stratigraphy that is summarized in
Table 3 and below.
The Chaudiere River drainage basin carries
drainage from the International Boundary
northward, through the Appalachian ridges into
the St. Lawrence River just opposite QuCbec
City. The Laurentides glaciers advanced southward into the basin several times during the
1598
CAN. J . EARTH SCI. VOL. 1 1 , 1974
TABLE2. Clastic dikes in unconsolidated sediments
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
Authors
Features
Origin
Anderson 1940
Till wedges
Birman 1952
Dreimanis 1935
Dreimanis 1969
Till dikes in weathered crystalline
bedrock
Upward going dikes
Till wedges
Dzulynski 1965
Clastic wedges
Goldthwait and Kruger 1938
Heron et el. 1971
Till dikes in weathered crystalline
bedrock
Sandy mud dikes
Hobbs 1907
Mud and sand dikes
Jenkins 1925a
Gravel, sand, silt, and clay dikes
Kruger 1938
Lundqvist 1967
Till dikes in weathered crystalline
bedrock
Till dikes
Lupher 1944
Clay, silt and gravel dikes
Monroe1932
Clay dikes
Moret 1945
Gravel dikes
Morner 1972, 1973
Till wedges
Oldham and Mallet 1872
Silt and sand dikes
Oomkens 1966
Sand dikes
Reimnitz and Marshall 1965
Sand dikes
Schafer 1969
Till wedges
Schwarzbach 1952
Strangways 1821
Sand wedges
Clay dikes
Whitten 1898
Clay dikes
Quaternary, temporarily ponding lakes in the
Chaudibre basin during each advance and during
each retreat. The outlets for these lakes were
southward and eastward: through cols in the
highlands of central and western Maine. The
possible levels of the lakes were closely controlled
by the altitude of those cols so that the levels of
the various stages of impoundment are very well
known (Shilts 1969; McDonald and Shilts 1971).
At the onset of the last glaciation, a vast lake,
Filling from above of fissures in frozen
sands.
Filling from above of former ice wedges.
Glaciotectonic.
Filling from above of fissures caused by
glacial drag.
Injection due to overloading in deposits
with a reverse density gradient (laboratory
experiments).
Filling from above by pressure of overlying
glacier ice.
Filling from above of fractures produced
by slump or hillside creep.
Injection from below into fissures caused
by earthquake.
Filling from above and injection from
below of fissures caused by earthquake.
Filling from above of fissures by overlying
glacier ice.
Filling from above of fissures caused by
glacier drag.
Filling from above of fissures most
resulting from melting of buried ice.
Filling from above of cracks caused by
subsoil creep.
Filling from below of fissures resulting
from landsliding and mass movement.
Filling from above of fissures caused by
glacial drag, and wedges formed by
squeezing in by glacial drag.
Injection from below into fissures caused
by earthquake.
Injection from below into desiccation
cracks, and filling from above by eolian
sand.
Injection from below into cracks caused by
earthquake.
Filling from above of tension cracks
caused by glacial drag.
Filling of fissures related to landsliding.
Filling from above of fissures and cracks
caused by earthquake.
Filling from above of fissures when overridden by glacier ice.
Glacial Lake Gayhurst, existed in the upper
Chaudibre and St. Francis River valleys
(McDonald and Shilts 1971). Thick sequences of
sediments were deposited in this long-lived lake
and the various facies have been formally named
the Gayhurst Formation. Where not removed by
glacial erosion, the Gayhurst Formation underlies Lennoxville Till in all areas below 470 m
altitude, the maximum altitude of the main body
of Lake Gayhurst. In the Chaudikre valley,
DIONNE AND SHILTS: CLASTIC DIKE
TABLE
3. Quaternary stratigraphic column, South Eastern Quebec'
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
Time-stratigraphic
unit
Rock-stratigraphic Unit
Past-Lemomille S e + e n t s
(younger than 13 000 years)
Lennoxville Till
Dralet lentil
C--
(
Gayhurst Formation (older than 20 000 years)
Chaudiere Till
Massavippi Formation (older than 40 000 years)
Johnville Till
-
Pre-Wisconsin stage
-
Pre-Johrmille Sediments
'From McDonald and Shilts 1971, p. 685.
Abundant evidence from till fabrics, striations,
end moraine orientations, and rock, mineral and
chemical dispersal data indicate that the important ice movement direction during the
Lennoxville glaciation was toward 110"-130"
(Shilts 1969, 1973). Locally, ice movement was
at right angles to this trend during advance and
retreat of the Lennoxville glacier and St. Ludger
is located near the centre of a late-glacial ice cap
that persisted after the main retreat of the
Lennoxville glacier (Lamarche 1971; Gadd et al.
1972).
Certain facts concerning environments of
deposition of the till wedge and associated sediments may be deduced from the brief discussion
above: (1) The Lennoxville glacier advanced
over the site while standing in a minimum of
100 m to a maximum of 130 m of water of
Glacial Lake Gayhurst; thus, it is unlikely that
underlying sediments were frozen; (2) Flow over
the site was probably first southerly to southwesterly shifting later to east-southeast flow as
the glacier thickened (Shilts 1973, pp. 197-199);
(3) The underlying sandy sediment is probably a
facies of the Gayhurst Formation as are the
FIG.1. Location map, St. Ludger, southern Qukbec.
varves that occur in the till and as inclusions in
between St. Ludgerand Lac-Mtgantic, exception- the sand; (4) Since there was deep water in conally clayey till, derived in large part from the tact with the remnant ice cap as its south edge
varved facies of the Gayhurst Formation, forms retreated northward and because of the lack of
the surface till and is called the Drolet lentil of periglacial features proved in the Chauditre
Lennoxville Till (Shilts 1973).
valley by careful mapping, it is unlikely that the
1600
CAN. J . EARTH SC:I. VOL. 11, 1974
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
sediments at St. Ludger were subjected to postglacial permafrost.
Description of Exposure and Dike
The face of the St. Ludger exposure was
artificially excavated and trended approximately
east-west at the time of observation in 1969; a
year and a half later, the exposure was completely obscured by slumping. The section consisted of 4 to 5 m of a complex mixture of
Lennoxville Till, Gayhurst Formation (varves),
and Drolet lentil (clay till) (Table 4). A large,
wedge-shaped dike of till projected into the
underlying sand near the center of the exposure,
and smaller, though similar, dikes projected 25
to 40 cm into the sand at the west end of the
exposure (Figs. 2 and 3). The sand near the
till-sand contact was everywhere tightly
cemented by calcium carbonate to a thickness
of 10 to 15 mm out or down from the till. The
horizontal upper surface of the sand was overlain by 10 to 20 cm of apparently undisturbed
varves, texturally similar to those found as inclusions in the sand and till (Fig. 4). These varves
were missing at the wedges but the portion displaced by the large wedge had been 'peeled' up
and overturned to the east or southeast.
The structure of the till-varve complex is very
intricate. A fabric measured in the till has
maxima at 110" and 130°, directions that agree
well with known directions of movement of the
Lennoxville glacier (Shilts 1973). Layers of
varves, apparently sheared into the till, dip 24"
toward 150" (southeastward) and their upper
terminations are overturned toward the east or
southeast. However, other planar elements that
have the aspect of shear planes dip toward the
west or northwest. A varve layer on the southeast side of the till wedge is also overturned to
southeast.
The structures described could be produced if
slices of till were originally emplaced by shear
stacking; each till slice would have been slid into
place on a layer of varves. Shear stacking, often
with contorted water-laid sediments separating
till slices, is a common phenomenon in most till
exposures in the upper Chaudikre valley.
After till had been stacked in subhorizontal
slices, it could have been folded or disturbed by
some change in the regime of overriding ice.
What that change might have been is entirely
speculative but change in ice-flow direction,
change in thickness of overriding ice, or change
in temperature environment of the glacier base
are some possible changes that might have taken
place. In addition, the Lennoxville glacier must
have stood in about 100 to 130 m of water of
glacial lake Gayhurst when it first advanced over
the site and later basal movement and deposition
might have been quite different in the absence of
large amounts of water.
The dike itself is 40 cm wide at the top
tapering to 25 cm at its lowest exposed point. It
is exposed for 2 m and may be as much as 5 m
deep, judging from the rate of tapering. It
strikes at 020" and is slightly curved on the eastfacing side (Fig. 5). The strike of the dike is precisely at right angles to the most prominent
direction of striae in the region, 110" (eastsoutheast). The top of the northwest-facing side
of the dike is about 10 cm lower than the southeast (Fig. 3). A break in the horizontal varve
layer that separates the till complex from sand
occurs at the wedge and till in the dike is similar
to that at the top of the section. These facts,
coupled with the downward tapering of the dike
and the downward termination of smaller,
similar dikes at the west end of the section, lead
the authors to the conclusion that the dike was
emplaced into the sand from above.
Origin and Significance o m e St. Ludger
Till Dike
According to Dreimanis (1969) till wedges may
result from injection of till from the base of a
glacier into friction cracks formed by glacial
drag over frozen sand. Morner (1972) suggested
that till wedges can also result from squeeze-in
when a glacier overrides unfrozen or subaquatic
sediments, till being simply squeezed into the
underlying, usually deformed, sediments.
The till dike at St. Ludger is thought to have
been produced under the first process, i.e. by
injection or infilling of till from the base of a
glacier into a crack formed when the underlying
sands were overridden by ice. The formation of
the crack in the essentially cohesionless sand
deposit suggests that the sediments were saturated and frozen at some time during overriding,
because it is hard to conceive of conditions under
which clean, medium-grained sand could have
had enough tensile strength to be fractured under
tensile stress. It is possible that frozen Gayhurst
sands were broken under ice pressure and till
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
DIONNE AND SHILTS: CLASTIC DIKE
1601
FIG.2. The St. Ludger section showing position of till dike; a,Lennoxville till; b, Gayhurst sand.
Note a small till dike at right (arrow). (Shilts - GSC 154492, July 1969).
FIG.3. View of the St. Ludger till dike showing (a) overlying Lennoxville till, (b) a thin unit of
varves, and (c) underlying Gayhurst sand. Note that varves are interrupted at dike and overturned to
southeast on the left side of dike, and that the northwest facing side of dike is about 10 cm lower than
the southeast. Glacier flow from right to left (arrow). (Dionne, July 1969).
was subsequently injected into the crack from would allow unfrozen till to be injected into a
the base of the glacier. However, Worsley (1972) crack.
Because it is suggested that the glacier adcorrectly points out that it is unlikely that a substrate could remain frozen under conditions that vanced over lake sediments when the ice front
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
1602
CAN. J. EARTH
SCI. VOL. 11, 1974
FIG.4. Close view of St. Ludger section near dike showing the three units described in text: a,
Lennoxville till at top; b, varves; and c, Gayhurst lacustrine sand at base. Note clay forming shear
planes (arrows) dipping toward southeast (planes dip 24" toward 150"); shear planes were probably
overturned by overriding during late glacier movement from the NW. (Shilts - GSC 154399, July
1969).
FIG.5.
Close view to the St. Ludger till dike; edges of dike (arrow) are cemented by CaCo3. Note
curvature of dike. Glacier flow from right to left. (Shilts - GSC 154490, July 1969).
TABLE
4.
Description of till dike exposure
Location: Road cut on south side of St. Ludger, 0.16 km W of St. Ludger Church; Lat. 45"44'3OU N ; Long.
70°41'45" W; Altitude of top: 319 m.
Unit
Thickness
Sandy, compact, oxidized, non-calcareous, stony till with inclusions of contorted varves and clay
till; numerous shear planes with apparent dips both east and west; a wedge-shaped, dike-like
protrusion of till, 40 cm wide at top to 25 cm wide at base extends 200 cm downward into underlying
sand; trend of dike is 020"; fabric with maximum at 110'-130" measured 60 cm above base of till.
5m
Oxidized, non-calcareous slightly disturbed silt-clay laminae, apparently sheared into place; laminae are
cut by till dike.
10 cm
Massive, structureless, medium-grained sand containing tabular clasts of silt-clay laminae to 30 cm
maximum diameter; sand is carbonate cemented 10 mm downward from overlying silt-clay and
10 cm outward from till dike.
100 cm
Slump to road
90 cm
DIONNE AND SHILTS: CLASTIC DIKE
was standing in 100 to 130 m of water (Shilts
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
1969)ya
remains to be
It seems
that
sands may occur under such
a depth of water. Freezing, therefore, would have
to occur after the Lennoxville glacier overrode
the site. Since it is questionable whether uncon"lidated sediments freeze under a temperate
glacier, either the glacier was frozen to the base
or freezing is simply not necessary to form such
cracks. The fact that the wedge is oriented at
right angles to the direction of movement
strongly supports the conclusion that the crack(s)
were formed by tensile stresses caused by glacier
overriding.
Another problem arises from the fact that the
St. Ludger till dike is slightly convex downglacier rather than dipping down-glacier as
reported by Dreimanis (1969) and Morner
(1972, 1973). As the sands in the exposure
showed no obvious stratification, it is difficult
to determine if the glacier slightly displaced the
upper portion of the deposit in overriding it,
changing the primary orientation of the dike;
some sliding movement may also have occurred
afterwards. It is noteworthy that the "clay dikes"
reported by Whitten (1898) and attributed to
glacial action are also bent up-ice.
Conclusions
Till dikes can be formed (1) by cracking and
filling of frozen underlying sediments under
glacial drag, or (2) by squeezing into or cracking
of unfrozen underlying sediments. According to
Dreimanis (1969) and Morner (1972) their
orientation may serve as a reliable indicator of
the direction of glacial movement when other
evidence is absent or when the application of
other criteria such as till fabric is time consuming.
The till dike at St. Ludger formed during
Lennoxville glaciation when the Laurentides
ice sheet overrode lacustrine sands of the Gayhurst Formation. Sand was cracked under ice
motion and till was injected into the crack from
above. The cracking is at right angles to the
direction of ice flow. If the sand was frozen, the
Lennoxville glacier must at one time have been
frozen to its base because the glacier first covered
the St. Ludger site while fronting in a deep lake.
Alternatively, freezing may not be required to
form tension cracks in unconsolidated sediment
under stress from an overriding glacier.
1603
ANDERSON,
J. G. C. 1940. Glacial drifts near Roslin,
Midlothian. Geol. Mag., 77, pp. 47W73.
ANDRIEUX,
J. 1967. Etude de quelques filons clastiques
intraformationnels du flysch albo-aptien des zones
externes du Rif (Maroc). Bull. Soc. Gtol. Fr., (7th
ser.), 9, pp. 844-849.
ANKETELL,
J. M., CEGLA,J., and DZULYNSKI,
S. 1970.
On the deformational structures in systems with
reversed density gradients. Ann. Soc. GCol. Pol., 40,
vv. 3-30.
ARAI,J. 1957. On some Cenozoic clastic dikes from the
Chichibu Basin, Saitama Prefecture, Japan. Bull.
Chichibu Mus. Nat. Hist., 9, pp. 3147.
BIRMAN,
J. H. 1952. Pleistoc6ne clastic dikes in weathered
granite-gneiss, Rhode Island. Am. J. Sci., 250, pp.
721-734.
BUTRYM,J., CEGLA,J., DZULYNSKI,
S., and NAKANIEZNY,S. 1964. New interpretation of periglacial
structures. Folia Quaternaria, 17, pp. 1-34.
CAMPBELL,
M. R. 1904. Conglomerate dikes in southern
Arizona. Am. Geol., 33, pp. 135-138.
CASE,E. C. 1895. On the mud and sand dikes of the White
River, Miocene. Am. Geol., 15, pp. 248-254.
COLACICCHI,
R. 1959. Dichi sedimentari del Flysch
oligominovenico della Sicilia Nord-Orientale.
Eclogae Geol. Helv., 51, pp. 901-916.
CROSS,W. 1894. Intrusive sandstone dikes in granite.
B&. Geol. Soc. Am., 5, pp. 225-230.
DE JONG,J. D. 1971. Molasse and clastic-wedge sediments of the southern Cantabrian Mountains (NW
Spain) as geomorphological and environmental indicator. Geol. Mijnbouw, 50, pp. 399-416.
DILLER,
J. S. 1890. Sandstone dikes. Bull. Geol. Soc. Am.,
1, pp. 4 1 1 4 2 .
DIONNE,J. C. 1970. Structures skdimentaires dans du
fluvio-glaciaire,Lac-Saint-Jean, QuBbec. Rev. GBogr.
Montrkal, 24, pp. 255-263.
-- 1971. Dyke de till dans sables glacio-lacustres,
haute vallee de la Chaudiirre, (resume). Ann.
ACFAS, 38, p. 72.
DREIMANIS,
A. 1935. The rock-deformations caused by
inland-ice on the left bank of the Daugava at Dole
Island. near Riga in Latvia. Riga, Izdevis A. Gulbis,
pp. 12-18.
-- 1969. Till wedges as indicators of direction of
glacial
movement. Geol. Soc. Am., Abstr. Prog., 7,
pp. 52-53.
DYLIK,J. and MAARLEVELD,
G. C. 1967. Frost cracks,
frost fissures and related ~olygons.
Mededel. Geol.
- -Stichting, 18, pp. 7-22.
DZULYNSKI,
S. 1965. Experiments on clastic wedges. Bull.
Acad. Pol. Sci., SCr. Gtol. Geogr., 13, pp. 301-303.
DZULYNSKI,
S. and RADOMSKI,
A. 1956. Zagadnienie zyl
klastycznych na tle sedymentacji flizu (Clastic dikes
in the Carpathian flysch). Ann. Soc. GBol. Pol., 26,
pp. 225-264.
DZULYNSKI,
S. and WALTON,
E. K. 1965. Load, flow and
injection structures. In: Sedimentary features of
flysch and greywackes. Elsevier, Amsterdam, pp.
143-193.
ELRIDGE,
G. H. 1906. The formation of asphalt veins.
Econ. Geol., 1, pp. 437444.
FAIRBRIDGE,
R. W. 1946. Submarine slumping and location of oil bodies. Bull. Am. Ass. Pet. Geol., 30, pp.
84-92.
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
1604
C A N . J . EARTH S(:I: VOL. 11, 1974
GADD,N. R., MCDONALD,
B. C., and SHILTS,W. W.
1972. Deglaciation of southern Quebec. Geol. Surv.
Can., Pap. 71-47, 19 p.
GARY,M., MCAFEE,R., and WOLF,C. L. (Eds.). 1972.
Glossary of geology. Am. Geol. Inst., Washington,
857 p.
GILBERT,
G. K. 1880. Report on the Geology of the
Henry Mountains (Utah). U.S. Geogr. Geol. Surv.,
Rocky Mountains Region, pp. 1-170.
GOLDTHWAIT,
J. W. and KRUGER,
F. C. 1938. Weathered
rock in and under the drift in New Hampshire. Bull.
Geol. Soc. Am., 49, pp. 1183-1 197.
GOTTIS,C. 1953. Les filons clastiques "intraformationnels" du "flysch" numidien tunisien. Bull. Soc.
Geol. Fr., (6th ser.), 3, pp. 775-783.
GRABAU,
A. W. 1900. Siluro-Devonic contact in Erie Co.,
New York. Bull. Geol. Soc. Am., 11, pp. 357-361.
GRESLEY,
W. S. 1898. Clay-veins vertically intersecting
coal measures. Bull. Geol. Soc. Am., 9, pp. 35-58.
HAY,R. 1892. Sandstone dikes in northwestern Nebraska.
Bull. Geol. Soc. Am., 3, pp. 50-55.
HAYASHI,
T. 1966. Clastic dikes in Japan. Jap. J. Geol.
Geogr., 37, pp. 1-20.
H. S. 1971.
HERON,S. D., JUDD,J. B., and JOHNSON,
Clastic dikes associated with soil horizons in the
North and South Carolina Coastal Plain. Bull. Geol.
Soc. Am., 82, pp. 1801-1810.
HOBBS,W. H. 1907. Earthquakes. An introduction to
seismic geology. Appleton, New York, 336 p.
IRVING,
R. D. 1883. The copper-bearing rocks of Lake
Superior. U.S. Geol. Surv., Monogr. V , 464 p.
JENKINS,
0 . P. 1925a. Clastic dikes of eastern Washington
and their geologic significance. Am. J. Sci., (5th
ser.), 10, pp. 234246.
19256. Mechanics of clastic dike intrusion. Eng.
Min. J. Press, 120, p. 12.
JOHNSSON,
G. 1959. True and false ice wedges in southern
Sweden. Geogr. Ann., 41, pp. 15-33.
KAISER,K. 1958. Wirkungen des pleistozanen Bodenfrostes in den Sentimenten der Niderrheinischen
Bucht. Eiszeitalter u. Gegenwart, 9, pp. 110-129.
KING,L. C. 1959. Denudational and tectonic relief in
southeastern Australia. Trans. Geol. Soc. South
Africa, 62, pp. 113-138.
KRUGER,
F. C. 1938. A clastic dike of glacial origin. Am.
J. Sci., 35, pp. 305-307.
LAMARCHE,
R. Y. 1971. Northward moving ice in thc
Thetford Mines area of southern Quebec. Am. J.
Sci., 271, pp. 383-388.
LAMBRECHT,
L. and THOREZ,J. 1966. Filons clastiques
intraformationnels dans le Namurien de Belgique.
C. R. Acad. Sci. (Paris), ser. D, 263, pp. 1556-1559.
LAWLER,
T. B. 1923. On the occurrence of sandstone
dikes and chalcedony veins in the White River
Oligocene. Am. J. Sci., (5th ser.), 5, pp. 160-172.
LUNDQVIST,
J. 1967. Submorana sediment i Jamtlands
Lan. (Submorainic sediment in the county of
Jamtland, central Sweden). Sver. Geol. Unders., ser.
C, 618, 267 p.
LUPHER,R. L. 1944. Clastic dikes of the Columbia Basin
region, Washington and Idaho. Bull. Geol. Soc.
Am., 55, pp. 1431-1461.
MARINOV,
T. M. 1971. Nakhodka klasticheskikh dayek
bliz S. Dospat (Zapadnyye Rodopy) (Clastic dikes
near Dospat, western Rhodope Mountains). Bulg.
Akad. Nauk Dokl., 24, pp. 1517-1520.
MARSCHALKO,
R. 1972. Termin: klastiche zily (The concept of clastic dikes). Geol. Prace Zpr., 58, pp.
231-238.
MCCALLIE,
S. W. 1903. Sandstone dikes near Columbus,
Georgia. Am. Geol., 32, pp. 199-202.
MCDONALD,
B. C. and SHILTS,W. W. 1971. Quaternary
stratigraphy and events in southeastern Quebec.
Bull. Geol. Soc. Am., 82, pp. 683-698.
MONROE,
W. H. 1932. Earth cracks in Mississippi. Bull.
Am. Ass. Pet. Geol., 16, pp. 214215.
MORET,L. 1945. A propos du mode de formation des
"filons clastiques." Ann. Univ. Grenoble, 21, pp.
99-101.
MORNER,
N. A. 1972. The first report on till wedges in
Europe and Late-Weichselian ice flows over southern
Sweden. Geol. Foren. Forh., 94, pp. 581-587.
.
1973. New find of till wedges in Nova Scotia,
Canada. Geol. Foren. Forh., 95, pp. 272-273.
NEWSON,
J. F. 1903. Clastic dikes. Bull. Geol. Soc. Am.,
14, pp. 227-268.
OLDHAM,
DR. and MALLET,
R. 1872. Notice on some of
the secondary effects of the earthquake of loth
January, 1869, in Cachar. Quat. J. Geol. SOC.
London, 28, pp. 255-270.
E. 1966. Environmental significance of sand
OOMKENS,
dikes. Sedimentology, 7, pp. 145-148.
PARKER,B. H. 1933. Clastic plugs and dikes of the
Cimarron Valley area of Union county, New Mexico.
J. Geol., pp. 38-51.
PAVLOW,
A. P. 1896. On dikes of Oligocene sands'nne in
the Neocomian clays of the district of Al~~tyr,
in
Russia. Geol. Mag., 3, pp. 49-53.
PETERSON,
G. L. 1968. Flow structures in sandstone dikes.
Sed. Geol., 2, pp. 117-190.
PETTIJOHN,
F. J. 1957. Sedimentary rocks. New York,
Harper and Row, 2nd ed., 718 p.
Pfwf, T. L. 1959. Sand-wedge polygons (tesselations) in
the McMurdo Sound region, Antarctica. Am. J. Sci.,
257, pp. 545-552.
POWELL,
C. M. 1969. Intrusive sandstone dykes in the
Siamo Slate near Negaunee, Michigan. Bull. Geol.
Soc. Am., 80, pp. 2585-2594.
PRUVOST,
P. 1943. Filons clastiques. Bull. Soc. GBol. Fr.,
(5th ser.), 13, pp. 91-104.
REIMNITZ,
E. and MARSHALL,
N. F. 1965. Effects of the
Alaska earthquake and tsunami on the recent deltaic
sediments. J. Geophys. Res., 70, pp. 2363-2376.
RUTTEN,M. G. and SCHONBERGER,
H. J. M. 1957. Synsedimentary sandstone dikes in the Aptien of the
Serre Chaitieu, southern France. Geol. Mijnbouw,
19, pp. 214220.
SCHAFER,
J. P. 1969. Structural relationship of tills in
western Connecticut. Geol. Soc. Am., Abstr. Prog.
7, p. 42.
SCHWARZBACH,
M. 1952. Ein Pseudo-Eiskeil aus den
Albaner Bergen bei Rom. Geol. Rundschau, 40, pp.
5657.
SELLY,
R. C. and SHEARMAN,
D. J. 1962. The experimental
production of sedimentary structures in quicksand.
Proc. Geol. Soc. London, 1599, pp. 101-102.
SHILTS,W. W. 1969. Pleistocene Geology of the Lac
Mkgantic region, southeastern Quebec, Canada.
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
DIONNE AND SHILTS: CLASTIC DIKE
Unpubl. Ph.D. thesis, Syracuse Univ., Syracuse,
New York, 154- p.
1973. Glacial dispersal of rocks, minerals, and
trace elements in Wisconsinan till, southeastern
Quebec, Canada. In: The Wisconsinan Stage. R.F.
Black et al. (Eds.), Geol. Soc. Am., Mem. 136, pp.
189-219.
SMITH,A. J. and RAST,N. 1958. Sedimentary dykes in the
Dalradian of Scotland. Geol. Mag., 95, pp. 234-240.
SMITH,K. G. 1952. Structure plan of clastic dikes. Trans.
Am. Geophys. Un., 33, pp. 889-892.
G. L. 1971. Sandstone
SMYERS,N. B. and PETERSON,
dikes and sills in the Mereno Shale, Panoche Hills,
California. Bull. Geol. Soc. Am., 82, pp. 3201-3207.
STEWART,
C. A. 1911. Note on a conglomerate dike in
Arizona. Science, 33, pp. 431-435.
STRANGWAYS,
T. H. F. 1821. Description of strata in the
Brook Pulcovea near the village of Great Pulcovea
in the neighborhood of St. Petersberg. Trans. Geol.
SOC.London, 5, pp. 382-458.
TEISSEYRE,
A. K. 1967. Clastic wedges in the Lower
1605
Carboniferous of the intrasudetic basin. Bull. Acad.
Pol. Sci., ser. GBol. GBogr., 15, pp. 15-22.
VINTANAGE,
P. W. 1954. Sandstone dikes in the South
Platte area, Colorado. J. Geol., 62, pp. 493-500.
WHITTEN,W. M. 1898. "Quicksand pockets" in "blue
clay" of South Bend. Proc. Indiana Acad. Sci.
(1897), pp. 234-240.
M. Y. 1927. Sandstone dykes in southeastern
WILLIAMS,
Alberta. Trans. Roy. Soc. Can., 21, (3rd ser., 4th
sect.), pp. 153-174.
WORSLEY,
P. 1973. The first report on "till wedges" in
Europe. A discussion. Geol. Foren. Forh., 95, pp.
152-155.
YANUSHEVICH,
Y. D. 1972. 0 klasticheskikh daykakh v
otlozheniyakh Severo-Zapadnogo kavkaza (Clastic
dikes in deposits of the north western Caucasus).
Litol. Polez. Iskop., 3, pp. 162-164.
YOUNG,G. M. 1972. Downward intrusive breccias in the
Huronian Espanola Formation, Ontario, Canada.
Can. J. Earth Sci., 9, pp. 756-762.
Can. J. Earth Sci. Downloaded from www.nrcresearchpress.com by Depository Services Program on 02/24/15
For personal use only.
This article has been cited by:
1. Emrys Phillips, Leanne Hughes. 2014. Hydrofracturing in response to the development of an
overpressurised subglacial meltwater system during drumlin formation: an example from Anglesey,
NW Wales. Proceedings of the Geologists' Association 125, 296-311. [CrossRef]
2. Emrys Phillips, Jez Everest, Helen Reeves. 2012. Micromorphological evidence for subglacial
multiphase sedimentation and deformation during overpressurized fluid flow associated with
hydrofracturing. Boreas n/a-n/a. [CrossRef]
3. Réda Samy Zazoun, Yamina Mahdjoub. 2011. Strain analysis of Late Ordovician tectonic events in
the In-Tahouite and Tamadjert Formations (Tassili-n-Ajjers area, Algeria). Journal of African Earth
Sciences 60, 63-78. [CrossRef]
4. Andrzej Hałuszczak. 2007. Dike-filled extensional structures in Cenozoic deposits of the Kleszczów
Graben (Central Poland). Sedimentary Geology 193, 81-92. [CrossRef]
5. Mattias Lind�n, Per M�ller. 2005. Marginal formation of De Geer moraines and their implications to
the dynamics of grounding-line recession. Journal of Quaternary Science 20:10.1002/jqs.v20:2, 113-133.
[CrossRef]
6. Kenneth F Rijsdijk, Geraint Owen, William P Warren, Danny McCarroll, Jaap J.M van der Meer.
1999. Clastic dykes in over-consolidated tills: evidence for subglacial hydrofracturing at Killiney Bay,
eastern Ireland. Sedimentary Geology 129, 111-126. [CrossRef]
7. Aleksis Dreimanis, Martin Rappol. 1997. Late Wisconsinan sub-glacial clastic intrusive sheets along
Lake Erie bluffs, at Bradtville, Ontario, Canada. Sedimentary Geology 111, 225-248. [CrossRef]
8. Jean-Claude Dionne. 1996. La basse terrasse à Petite-Rivière (Charlevoix, Québec) : un exemple
d’activité néotectonique à l’Holocène. Géographie physique et Quaternaire 50, 311. [CrossRef]
9. A. Thomas Martel, Martin R. Gibling. 1993. Clastic dykes of the Devono—Carboniferous Horton
Bluff Formation, Nova Scotia: storm-related structures in shallow lakes. Sedimentary Geology 87,
103-119. [CrossRef]
10. A.J. Van LoonChapter 3 The Recognition of Soft-Sediment Deformations as Early-Diagenetic Features
– a Literature Review 135-189. [CrossRef]
11. Sean J. Fitzsimons, Eric A. Colhoun. 1989. Pleistocene clastic dykes in the King Valley, western
Tasmania. Australian Journal of Earth Sciences 36, 351-363. [CrossRef]
12. A.V. Mudholkar, V.V. Peshwa. 1988. Clastic limestone dikes from the late Proterozoic Bhima Group,
South India. Sedimentary Geology 57, 221-229. [CrossRef]
13. Max Åmark. 1986. Clastic dikes formed beneath an active glacier. Geologiska Foereningan i Stockholm.
Foerhandlingar 108, 13-20. [CrossRef]
14. C.A. Boulter. 1986. Accretionary lapilli-filled clastic dykes: a comparison of compaction strain estimates
from dyke folding and lapilli shape factors. Journal of Structural Geology 8, 201-204. [CrossRef]
15. References 561-643. [CrossRef]
16. JAN MANGERUD, HANS-PETTER SEJRUP, EIVIND SØNSTEGAARD, SYLVI
HALDORSEN. 1981. A continuous Eemian-Early Weichselian sequence containing pollen and marine
fossils at Fjøsanger, western Norway. Boreas 10:10.1111/bor.1981.10.issue-2, 137-208. [CrossRef]
17. Robert F. Black. 1976. Periglacial features indicative of permafrost: Ice and soil wedges. Quaternary
Research 6, 3-26. [CrossRef]