According to the glacial theory, vast continental ice sheets spread out from their centers in
the Hudson Bay area radially in all directions. Ice eroded sedimentary rocks
along the border of the Canadian Shield, and scoured pre-existing river
valleys. This is supposed to have been the mechanism which produced
the rock basins that are now occupied by the Great Lakes. A radial
pattern of ice flow is attributed to the ice sheets in many geology
North of Lake Ontario, from Oshawa westward, and north of Lake
in the Tavistock-Woodstock area, the orientation of
drumlins indicates they were formed by a flow
towards the northwest. This is an enigma in the glacial
theory, as former ice sheets must have spread
from their centers where ice thickness was greatest. No force is
available to drive ice back from
its perimeter towards the northwest. Since ice was also
flowing south and southwest from these lake basins, the cause
of the northwesterly flow is a mystery.
A drumlin field containing about 300 drumlins with northwest
orientation occurs in the area around
Guelph, Ontario. The flow is believed to have come from out of the Lake
Ontario Basin to the south. The orientation of a group
of drumlins at Westover, between Guelph
and Dundas, indicates a westerly flow
direction. According to the glacial theory, the ice sheet must have
flowed uphill, out of Lake Ontario, over the cliffs of the
Niagara Escarpment, to form these drumlins. The drumlins and flutings
of the drumlin field around
Woodstock, north of Lake Erie, were also caused by a flow to
of the basin of Lake Erie. The trend of the drumlins in these areas
seems anomalous. Ice
is thought to have flowed southward from the Hudson Bay area, and
excavated the basins of Lake
and Lake Erie. From these basins, flow occurred towards the south,
southwest, west, and northwest. But why would ice have flowed
in such diverse directions north and south of the basins of
Lake Erie and Lake Ontario?
At Port Stanley, on the north shore of Lake Erie, there are bluffs of
drift material with a series of layers, grey at the bottom, followed by a layer of light
brown clay or silt, and a layer of clay at the top. The glacial theory says
ice overrode layers of drift during successive periods when
ice advanced and retreated. The Erie lobe of the ice sheet must have
attacked the bedrock, excavating the lake basin, and ascended the northern shore of the lake. As it
passed over the previously deposited drift, it failed to erode it, but
instead deposited another layer of drift over it, which was shaped into
View of the bluffs of drift near Port Stanley, Ontario. There
were few areas
where the proposed ice sheet could access the bedrock, to
derive source materials for manufacturing the later drift, once
earliest drift layers were deposited. Since drift
composition tends to
resemble that of the local bedrock, the source cannot be some
distant location. Access to source materials consisting
of suitable rock types is required for the manufacture of
the pebbles and boulders contained in coarse gravels in the glacial
environment. But the materials that ice
apparently over-rode were often unsuitable for producing
gravels. In many areas the ice must have over-rode silt,
clay or sand, not dolomite or
limestone bedrock. The bluffs at Port Stanley shown in the above
photo illustrate this type of
material. Boulders and pebbles of limestone and dolomite cannot be
from drift consisting of unconsolidated silt or
clay. Access to suitable bedrock materials by the ice
sheet would decline as more layers of drift were deposited.
The ice sheet apparently
eroded bedrock in the basins of Lake Erie and Lake Ontario while
depositing layers of drift over the areas north and south of the lakes.
In many areas the drift surface was streamlined into drumlins and
flutings. Meanwhile, other ice lobes advanced from
Huron and Georgian Bay, which opposed
flow directions of the Erie and Ontario lobes. These are called the
Huron and Georgian Bay lobes. Each of these are thought to have caused
drumlin fields where the trend of flow was southward, opposing the west
trend of the ice from the basins of lakes Erie and Ontario. This
direction of flow is indicated by the Woodstock and Guelph
drumlin fields. Where were all these lobes flowing to? What was
the force driving
the lobes from the northwest, north, east and southeast?
Glacialists invoke "oscillating" lobes of the ice sheet
that deposited debris from various locations.
To attack the bedrock beneath the drift, the ice sheet must have
excavated an enormous volume of rock material, that was subsequently
deposited as drift, presumably under the ice or in proglacial lakes
when the ice sheet melted. This drift exhibits distinctive layers or
formations called tills, and their distributions are mapped on maps
such as the Quaternary Geologic Map of the Lake Erie 4° x
6° Quadrangle, United States and Canada, by the USGS. Subsurface
information on the various formations has been obtained from well logs.
Most of the drift formations in the
region north of Lake Erie are listed in the table below. The drift
thickness varies from about
30 m - 90 m.
Relations of Drift formations in Southern Ontario
Rannoch Till (Huron Lobe) - silty clay, calcareous, overlies Tavistock Till.
Stratford Till (Huron - Georgian Bay Lobe) - sandy silt, calcareous, overlies Tavistock Till and Mornington Till.
Elma Till (Georgian Bay Lobe) - sandy silt and clayey silt, calcareous, overlies the Mornington Till.
Till (Huron - Georgian Bay Lobe) - type section: Conestogo Dam. A
brown or dark grey silty clay till, overlies Tavistock Till.
Till (Huron - Georgian Bay Lobe) - silty clay, coarse grained,
coarsening towards Woodstock, calcareous, overlies Port Stanley Till,
Stirton Till and Maryhill Till.
Halton Till ((Erie - Ontario Lobe) - silt, overlies Wentworth Till.
Wentworth Till (Erie Lobe) - overlies Port Stanley Till.
Stanley Till (Erie Lobe) - clayey to silty clay, calcareous. It is
thought to have been deposited over a period that spans all the above
named tills. It occurs at the surface in the area of the Guelph drumlin
field. Overlies Maryhill Till.
Maryhill Till (Erie Lobe) -
clay-rich, with sand and gravel. Type section, banks of the Grand River
at Homer Watson Park. Overlies Catfish Creek Till.
Stirton Till (Huron - Georgian Bay Lobe) - overlies Catfish Creek Till.
Creek Till (Huron Lobe - southwest ice flow) - coarse grained, silty to sandy till,
stony in some areas, compact, calcareous. Widespread in southwestern Ontario.
Till (Ontario or Erie Ice Lobe) - a reddish, fine textured till. The
red color is attributed to its derivation from the Queenston Formation
east of the Niagara Escarpment.
Each till in the list is associated with one or two
glacial 'lobes'. The flow patterns of these lobes are determined
from studies of the orientation of the drumlins, and lithology.
The Quaternary Geology map below, produced with data from the
Government of Ontario LIO
site, shows the regions where the various drift units are exposed in
Southwestern Ontario. (Some colors are missing from the
legend. The light brown, orange, and cream colors
indicate glaciofluvial deposits, and purple areas, e.g.
on the Niagara Peninsula, indicate glaciolacustarine
silt and clay deposits. Note that the order is inverted,
later tills are those with higher numbers. For full
details see the LIO site.)
Ice lobes are thought to have retreated from
the Waterloo region
towards their respective lake basins. Most of the tills shown overlie a
other tills, and evidently very little bedrock was exposed, once the
lower layers had been deposited. As more data from well logs
accumulates, the extent of buried drift units is mapped in more
greater areas. The earlier units, such as Catfish Creek Till, are
reported to be widely distributed over Southern Ontario,
so the ice lobes must have had limited areas of exposed
bedrock to act upon in order to derive the
pebbles and boulders that occur in the gravels associated with
glacofluvial deposits overlying those units. Many reports state that
most of the boulders and pebbles in these layers were derived from
local bedrock. How was the local bedrock extracted by the ice if
bedrock was buried beneath the previously deposited layers of drift?
Locations of Paleozoic bedrock formations below the drift in Southern
Ontario. Map prepared using data from the Government of
As the hypothetical ice lobes oscillated over
Southern Ontario peninsula, they over-rode the previously
deposited layers of drift, but they
apparently did so without disturbing them, as in most areas the patterns
cross-strata in unconsolidated silt and sandy drift remain intact.
Meanwhile the same ice sheet, which was so gentle when passing over
stratified drift of drumlins, is thought to have
bedrock in the lake basins.
map at right, from the USGS Quaternary Geologic Map of the Lake
Erie area, shows ice
lobes from Lake Huron, Lake Erie, Georgian Bay, and Lake
Ontario flowing out of their basins, in various
directions. Even more complex flow patterns are proposed for ice lobes
of earlier periods. Note that the southern limit of the drift is
only a little way south of the eastern end of Lake Erie. The force that
caused the northward flow of the ice lobes out of lakes Erie and
Ontario is mysterious. Why would the ice have flowed both
northwest and southeast out of Lake Erie?
Image credit: U.S. Geological Survey, Department of the Interior/USGS
The reason for the curious patterns of flow that caused the drumlin fields in
the areas north of Lake Erie and Lake Ontario is not well explained in the glacial
theory. These problems can resolved by the writer's in situ disintegration
theory, which assumes powerful currents swept the area of the
Great Lakes, and excavated the lake basins, and streamlined the area.
were generated by tectonic
uplift when the land was submerged. A series
uplifts raised the Canadian Shield above the sea. The currents
generated as the submerged crust was raised eroded the Paleozoic sediments that
were once present over much of the Shield. The sedimentary
formations that are now terminated at the Niagara Escarpment once
extended further east, over the Canadian Shield, but these rocks were eroded as the earth's crust was raised.
Fast currents excavated the basins
of the Great Lakes and thousands of other lake basins along the perimeter of the Shield. Erosion
of overburden was accompanied by a process of disintegration of the newly exposed
rock, which formed the mantle of drift. Erosion of deep lake basins and formation of escarpments
was aided by the process of disintegration. The Great Lakes
basins are evidence of former fast currents, which removed most of the
disintegrated sediment and deposited it in
distant regions. Drumlin fields in northwestern New York, and lake basins such as
the Finger Lakes, and drumlin fields in Southern Ontario and other regions, and the Great Lakes, all show the streamlining and
erosional effects of powerful currents, such as those generated by a series of uplifts centered in
the Canadian Shield, when the continent was submerged. The uplift of
Shield spilled overlying waters towards the south and southeast.
Vortices which developed in the currents caused the formation
of the drumlin fields.
effects of longitudinal vortices in currents are especially
evident north of Lake Ontario in the
drumlin field around Peterborough, where thousands of drumlins show the
effect of the currents. The image at right is a Digital Elevation
Model (DEM) of part the drumlin field, in the area east of Peterborough
including the northern end of Rice Lake. Some drumlins are islands in
the lake. The current flow was toward the south.
Similar streamline effects occur in Northwestern New York. The
erosion of the deep troughs of the
Finger Lakes, in this environment of catastrophic flow, was
by the contemporaneous disintegration of rock.
Uplift of the highlands in New York, Pennsylvania and Ohio
spilled flood water to the northwest, over
Southern Ontario, forming the drumlin fields north of Lake
Ontario and Lake Erie, with orientations indicating flow
towards the northwest. The radial patterns of drumlins in drumlin
fields is characteristic of current flow generated by tectonic
uplift. Other uplift events, centered in the Shield, spilled
flood water towards the southwest. As the highlands of New York and
Pennsylvania emerged from the water, southerly flow was deflected
toward the southeast
and toward the southwest, around the emerging land. Large drumlins
were modified as the depth decreased, and flow was
intensified, and several smaller ones formed on the same base.
Deep valleys and spillways were
formed as depth decreased and currents were concentrated in low areas.
Currents flowing towards the west-southwest,
generated by uplift in the submerged Shield, excavated
the basins of Lake Ontario and Lake Erie. Drumlins in the eastern basin of Lake Ontario record the trend of the current flow along the axis of the lake basin. Some of the
drumlins along the southern shore of the lake were cut in half by this
westerly current. Drumlins on the Niagara Peninsula indicate a westerly flow. A deep basin is present in the eastern part
of Lake Erie that was probably scoured by these currents.
The DEM image to the right shows the Dundas Valley, the Niagara
Escarpment, and the drumlins at Westover. The flow over the region
was westward, over the escarpment. Disintegration penetrated the
bedrock far below the surface in the Dundas Valley, where the depth to
bedrock is more than 300 m. The buried valley terminates abruptly a few
km west of Dundas.
The disintegration theory explains the drift as the result of a
chemical alteration and disintegration process in rocks as overburden
was removed. Extensive layers of drift having various
is expected in the disintegration interpretation, as the underlying
bedrock was also layered, and consisted of a variety of rock types.
is no requirement that bedrock was excavated and then redeposited
the disintegration theory.
The glacial theory says oscillating ice lobes gradually retreated into
the basin of Lake Ontario and formed dams for the series of
lakes that existed in the lake basins. As the ice lobes retreated,
ice-contact moraines would tend to be concave towards the
retreating ice, but
in fact, the drift features interpreted as moraines in the areas north
of Lake Erie and Lake Ontario where the drumlins indicate a northwest
flow are concave in the wrong direction for a glacial
interpretation. The shape of these ridges can be explained in the
theory as due to expansion effects. Upon
disintegration, extensive masses of drift expanded
outwards from the thicker
regions towards thinner areas. Frictional resistance to the
lateral movement caused thickening of the
drift at the perimeter of the expanding drift layer. The ridges of
formed in this manner were usually concave towards the thicker drift.
On the Bruce Peninsula the headlands of the Niagara Escarpmen
are streamlined, and aligned with the drumlins as shown in
image at right. These are streamlined bedrock features much greater in
scale than the drumlins, and so must have been formed when the region
was swept by currents with a greater depth than the currents which
formed the drumlins. The catastrophic currents generated by uplift of
the Canadian Shield was the environment in which the Great Lakes
were excavated. The sediment excavated from the lake
basins was removed from the area and transported to the continental
The process of in situ
disintegration that formed the drift was active during the erosion of
the lake basins by the catastrophic currents. This disintegration
penetrated far deeper in the valleys between the headlands of the
Niagara Escarpment than the excavation by currents. The Dundas
buried valley at the western end of Lake Ontario is more than 300 m
deep, but most of the drift in it was not eroded. Buried valleys
are common under the drift in areas around the Great Lakes, but they
don't support an interpretation that says they were formed by stream
erosion. The Dundas valley extends to below sea level. There valley
ends abruptly a few kilometers west of Dundas. The troughs at
Wiarton and Owen Sound and several other similar troughs were probably
once valleys buried in drift like the Dundas buried valley.
Ontario Ministry of Natural Resources. 1983. A Summary Report of the
Earth Science Areas of Natural and Scientific Interest in Cambridge
District. OMNR, Parks and Recreation Section, Central Region. 123 pp.
Karrow, P.F., 1974. Till Stratigraphy in Parts of Southwestern Ontario,
Geological Society of America Bulletin: Vol. 85, No. 5, pp.
Ontario Ministry of the Environment, Groundwater Monitoring Network Report
LIO Internet Map Browser System, Government of Ontario.
Quaternary Geologic Map of the Lake
Erie 4° x 6° Quadrangle, United States and Canada
Copyright © 2006
by Douglas E. Cox