The Ouimet Canyon: Pro Glacial and Sub Glacial Erosion

2. What is the Ouimet Canyon? A 2.5km glacially eroded canyon in North western Ontario. Located north east of Thunder Bay, ON near Dorion, ON. Canyon measures 100m deep. 60-200 m across depending on location. Canyon is now dry on the bottom but holds arctic fauna and areas of ice that remain year round (Wilkins 1994). Now made into a National Park and a tourist attraction. The Ouimet canyon is a 2 and a half kilometre canyon in North western Ontario that has been subject to glacial melt-water erosion. The area is located roughly 55km north east of Thunder Bay, Ontario (Teller and Thorleifson 1983) near the town of Dorion Ontario on highway 71. The canyon measures 100 m deep The width of the canyon varies from 60m to 200m across and varies throughout the 2.5km canyon. The canyon does not hold water anymore but holds arctic fauna and ice remains year round according to Wilkins in 1994. The canyon is now a national park and a major tourist attraction.The Ouimet canyon is a 2 and a half kilometre canyon in North western Ontario that has been subject to glacial melt-water erosion. The area is located roughly 55km north east of Thunder Bay, Ontario (Teller and Thorleifson 1983) near the town of Dorion Ontario on highway 71. The canyon measures 100 m deep The width of the canyon varies from 60m to 200m across and varies throughout the 2.5km canyon. The canyon does not hold water anymore but holds arctic fauna and ice remains year round according to Wilkins in 1994. The canyon is now a national park and a major tourist attraction.

3. Google Earth Image This is an areal view of the Ouimet canyon from google image. The canyon is located.... And 2 lakes sit at the southern base.This is an areal view of the Ouimet canyon from google image. The canyon is located.... And 2 lakes sit at the southern base.

4. Geology of North western Ontario The Ouimet canyon is located on the Canadian Shield. The Canadian Shield spans over 50% of the country (de Blij et al. 2005). The geology of the Shield is mostly Precambrian igneous along with metamorphic rocks. The Ouimet canyon area is made of Achaean rock structure Proterozoic tectonic activity known as the Keneenawan rift system existed in the region between approximately 1300 and 600 million years ago (Kor and Teller 1986) This resulted in an intrusive diabase sill that sits above a shale layer The Ouimet canyon is located on the canadian shield The canadian shield spans over 50% of the country The shield is mostly made up of Precambrian igneous and metamorphic rocks. The ouimet area is made up of archaean rocks shown shown in figure 4 from Teller and Thorleifson. Proterozoic Tectonic activity which is knows as the Keneenawan rift system existed between 1300 and 600 million years ago from Kor and teller. This resulted in an intrusive diabase sill that sits above a shale layer. The figure shows the diabase sill formed around Lake Nipigon in A. B shows the erosion around the diabase sill into the Archaean granite that lies around it. The Ouimet canyon is located on the canadian shield The canadian shield spans over 50% of the country The shield is mostly made up of Precambrian igneous and metamorphic rocks. The ouimet area is made up of archaean rocks shown shown in figure 4 from Teller and Thorleifson. Proterozoic Tectonic activity which is knows as the Keneenawan rift system existed between 1300 and 600 million years ago from Kor and teller. This resulted in an intrusive diabase sill that sits above a shale layer. The figure shows the diabase sill formed around Lake Nipigon in A. B shows the erosion around the diabase sill into the Archaean granite that lies around it.

5. Glacial Retreat and Drainage (Clayton 1983) Glacial retreat from the Lake Superior area is documented in Lee Claytons work on �Chronology of Lake Agassiz Drainage to Lake Superior� from 1983. The 5 phases of retreat include: The Cass Phase The Lockhart Phase The Moorhead Phase The Emerson Phase The Post- Emerson Phase The Lake Superior area was covered in ice during most of this time The Ouimet canyon is based on glacial Lake Agassiz outflow from the Laurentide ice sheet. As the ice retreated north eastward in 5 phases. The 5 phases include the cass phase, the lockhart phase, the moorhead phase, the emerson phase and the post-emerson phase During these 5 phases the Moorhead phase and the post-emerson phase are the only two phases that the lake nipigon basin was free from glacial ice.The Ouimet canyon is based on glacial Lake Agassiz outflow from the Laurentide ice sheet. As the ice retreated north eastward in 5 phases. The 5 phases include the cass phase, the lockhart phase, the moorhead phase, the emerson phase and the post-emerson phase During these 5 phases the Moorhead phase and the post-emerson phase are the only two phases that the lake nipigon basin was free from glacial ice.

6. The Cass Phase (Clayton 1983) During the cass phase the nipigon basin is covered by the superior lobe and the rainy lobe cover northwestern ontario at this time. The cass phase took place roughly 11,500 years ago according to clayton in 1983. The outflow was initiated by the red river lobe retreating.During the cass phase the nipigon basin is covered by the superior lobe and the rainy lobe cover northwestern ontario at this time. The cass phase took place roughly 11,500 years ago according to clayton in 1983. The outflow was initiated by the red river lobe retreating.

7. The Lockhart Phase (Clayton 1983) The lockhart phase took place 11,000 years ago. The red river lobe has retreated further north with lake agassiz expanding. The superior lobe begins to retreat but still covers the nipigon basinThe lockhart phase took place 11,000 years ago. The red river lobe has retreated further north with lake agassiz expanding. The superior lobe begins to retreat but still covers the nipigon basin

8. The Moorhead Phase (Clayton 1983) - The moorhead takes place 10,700 years ago This diagram shows the earl moorhead phase. The red river lobe has retreated north. Lake Agassiz is now in a more northernly position Lake nipigon is now free from the superior lobe. The arrows depict main drainage shown flowing through lake nipigon and to lake superior.- The moorhead takes place 10,700 years ago This diagram shows the earl moorhead phase. The red river lobe has retreated north. Lake Agassiz is now in a more northernly position Lake nipigon is now free from the superior lobe. The arrows depict main drainage shown flowing through lake nipigon and to lake superior.

9. Emerson Phase (Clayton 1983) The Emerson phase is 9,800 years ago The superior lobe as re advanced covering lake nipigon and lake superior in ice. The red river lobe is still far north The lake has moved south more due to the advancing ice.The Emerson phase is 9,800 years ago The superior lobe as re advanced covering lake nipigon and lake superior in ice. The red river lobe is still far north The lake has moved south more due to the advancing ice.

10. The Post- Emerson Phase (Clayton 1983) The post- emerson phase happens 800 years after the emerson phase The lake superior lobe has retreated further and exposes lake nipigon and lake superior Drainage begins again from lake agassiz to lake nipigon causing an overflow of lake nipigon to lake superior.The post- emerson phase happens 800 years after the emerson phase The lake superior lobe has retreated further and exposes lake nipigon and lake superior Drainage begins again from lake agassiz to lake nipigon causing an overflow of lake nipigon to lake superior.

11. Glacial Lake Agassiz Influence (Teller and Thorleifson 1983) The Ouimet canyon is formed due to the eastward discharge of Glacial Lake Agassiz. The canyon is located between the Lake Nipigon basin and the Lake Superior basin. Lake Agassiz drained into the Lake Nipigon basin through 5 systems which was made up of 17 different outlets. The Lake Nipigon basin would overflow creating a drainage system that is made up of 7 separate channels flowing from Lake Nipigon to Lake Superior: Wolf Wolfpup Shilabeer Black Sturgeon Nipigon Cash Pijitiwabik The canyon is located south west of the Wolf Channel As previously mentioned the canyon was formed due to the easkward discharge of glacial lake agassiz the canyon is located south of lake nipigon between nipigon and lake superior Lake agassiz drained into lake nipigon through 5 systems made up of 17 outlets. Lake nipigon would overflow and flow south to lake superior through 7 different channels. The channels include: wolf, wolfpup, shilabeer, black sturgeon, nipigon, cash, pijitiwabik The canyon is located south west of the wolf channel. The picture shows the main drainage from lake agassiz through lake nipigon continuing to lake superior.As previously mentioned the canyon was formed due to the easkward discharge of glacial lake agassiz the canyon is located south of lake nipigon between nipigon and lake superior Lake agassiz drained into lake nipigon through 5 systems made up of 17 outlets. Lake nipigon would overflow and flow south to lake superior through 7 different channels. The channels include: wolf, wolfpup, shilabeer, black sturgeon, nipigon, cash, pijitiwabik The canyon is located south west of the wolf channel. The picture shows the main drainage from lake agassiz through lake nipigon continuing to lake superior.

12. This is a map of the drainage outlet from lake agassiz to lake nipigon to lake superior from teller and thorleifson The area to focus on is numbers 20-26 which include the outlets of wolf, wolfpup, shilabeer, black sturgeon, nipigon, cash and pijitiwabikThis is a map of the drainage outlet from lake agassiz to lake nipigon to lake superior from teller and thorleifson The area to focus on is numbers 20-26 which include the outlets of wolf, wolfpup, shilabeer, black sturgeon, nipigon, cash and pijitiwabik

13. Canyon Creation (Wilkins 2005) Following intrusion of the diabase, sill cracks began to form. There are 2 beliefs of how the cracks formed: 1) cooling cracks 2) pressure cracks After this step there is some guessing and misconception according to Thunder Bay geologist Maurice Lavigne. Lavigne points out 3 separate theories: 1) multiple glacial periods affected the cracks in the diabase causing the rock to become weak and loosen, during glacial outflow the rocks were eroded 2) according to the park, the ice was the factor for the failure of the sill 3) Lavigne believes that glacial outflow migrated south through the diabase sill and eroded the weak shale layer. Through time the shale eroded creating a tunnel which eventually caused the upper diabase to fail creating the talus slopes seen today Once the diabase sill was formed cracks in the sill began to form 2 beliefs on sill crack formation is through 1) cooling cracks and 2) pressure cracks. After figuring out the cracks Maurice Lavigne put in some insight on the guessing game that happens after. Lavigne states that there are 3 separate theories 1) the multiple glaciation caused the cracks in the diabase which weaken the rocks and allowed them to loosed and begin to erode 2) the park believes the ice caused the failure in the sill 3) lavigne believes the glacial outflow migrated south through the diabse sill and eroded the weak shale layer below. Through time a tunnel was carved below the diabase causing it to fail and the talus slope to be formed that are seen today.Once the diabase sill was formed cracks in the sill began to form 2 beliefs on sill crack formation is through 1) cooling cracks and 2) pressure cracks. After figuring out the cracks Maurice Lavigne put in some insight on the guessing game that happens after. Lavigne states that there are 3 separate theories 1) the multiple glaciation caused the cracks in the diabase which weaken the rocks and allowed them to loosed and begin to erode 2) the park believes the ice caused the failure in the sill 3) lavigne believes the glacial outflow migrated south through the diabse sill and eroded the weak shale layer below. Through time a tunnel was carved below the diabase causing it to fail and the talus slope to be formed that are seen today.

14. Talus Slopes - This picture shows the talus slopes that are located on the canyon floor.- This picture shows the talus slopes that are located on the canyon floor.

15. Ouimet Canyon Erosion Geologists believe the Canyon was not created by a Lake Nipigon basin flood. The canyons elevation and location show that the it laid outside the main drainage areas of Glacial Lake Agassiz. (Kor and Teller 1986) Along with this the canyon is too deep and not wide enough to have been related to a large discharge event (Kor and Teller 1986) The canyon is suggested to have been eroded by sub-glacial and pro-glacial melt-water (Kor and Teller 1986; Teller and Thorleifson 1983) Definitions: Subglacial- �material carried under a glacier or ice sheet. Sub-glacial melt-water streams flow in tunnels under a glacier ice sheet.� (de Blij et al. 2005) Proglacial- �beyond the limits of a glacier or ice sheet. A proglacial lake is in contact with the ice front along part of its margins.� (Trenhaile 1990) Geologists believe the canyon was not created by a lake nipigon basin flood. The canyons elevation and location show that the canyon lies outside the lake nipigon discharge area. The canyon is also too deep and not wide enough to support a large discharge hypothesis The canyon has been suggested by many to have been shaped by sub glacial and pro glacial melt water events. Possibly due to the phases of glacial retreat. Definitions of subglacial and proglacial are laid out here. Subglacial- �material carried under a glacier or ice sheet. Sub-glacial melt-water streams flow in tunnels under a glacier ice sheet.� (de Blij et al. 2005) Proglacial- �beyond the limits of a glacier or ice sheet. A proglacial lake is in contact with the ice front along part of its margins.� (Trenhaile 1990) Geologists believe the canyon was not created by a lake nipigon basin flood. The canyons elevation and location show that the canyon lies outside the lake nipigon discharge area. The canyon is also too deep and not wide enough to support a large discharge hypothesis The canyon has been suggested by many to have been shaped by sub glacial and pro glacial melt water events. Possibly due to the phases of glacial retreat. Definitions of subglacial and proglacial are laid out here. Subglacial- �material carried under a glacier or ice sheet. Sub-glacial melt-water streams flow in tunnels under a glacier ice sheet.� (de Blij et al. 2005) Proglacial- �beyond the limits of a glacier or ice sheet. A proglacial lake is in contact with the ice front along part of its margins.� (Trenhaile 1990)

16. Conclusion The Ouimet canyon is an example of erosion from glacial discharge in the Canadian Shield. Many canyons surrounding the Ouimet are similar in nature but some still contain streams. The canyon now serves as a tourist destination and a scientific observational area due to the arctic fauna and ice on the canyon floor. Currently parallel cracks are forming next to the canyon. Large blocks of diabase are falling from the sides of the canyon. A reason to why the canyon floor is restricted to visitors and only open for scientific research (Wilkins 1994) Overall the canyon is an example of the power that mass amounts of water have on a relatively hard geological area. In conclusion the ouimet canyon is an example of erosion from glacial discharge in the canadian shield. Many canyons surrounding the Ouimet are similar in nature but some still contain streams The canyon now serves as a tourist destination and a scientific observational area due to the arctic fauna and ice on the canyon floor. Researchers are fascinated with the floor and are making sure the area is preserved. Currently parallel cracks are forming next to the canyon. Large block of diabase are falling from the sides of the canyon wall. Overall the canyon shows the power of mass amounts of water that have affected a hard geological area. The picture shows the park now with 2 separate viewing �pods� and picnic areas.In conclusion the ouimet canyon is an example of erosion from glacial discharge in the canadian shield. Many canyons surrounding the Ouimet are similar in nature but some still contain streams The canyon now serves as a tourist destination and a scientific observational area due to the arctic fauna and ice on the canyon floor. Researchers are fascinated with the floor and are making sure the area is preserved. Currently parallel cracks are forming next to the canyon. Large block of diabase are falling from the sides of the canyon wall. Overall the canyon shows the power of mass amounts of water that have affected a hard geological area. The picture shows the park now with 2 separate viewing �pods� and picnic areas.

17. References Clayton, L. 1983. Chronology of Lake Agassiz Drainage to Lake Superior. In Glacial Lake Agassiz. Edited by J.T. Teller and L. Clayton. The Geological Association of Canada, St. John�s, Newfoundland. pp. 291-307. de Blij, H.J., Muller, P.O., Williams, R.S., Conrad, C.T., and Long, P. 2005. Physical Geography: the global environment. Oxford University Press, Don Mills, ON Franklin, J.M., McIlwaine, W.H., Poulsen, K.H., and Wanless, R.K. 1980. Stratigraphy and depositional setting of the Sibley Group, Thunder Bay district, Ontario Canada. Canadian Journal of Earth Sciences, 17(5): 633-651. Kehew, A.E., and Lord, M.L. 1989. Canadian Landform Examples- 12: Glacial Lake Spillways of the Central Interior Plains, Canada- U.S.A. The Canadian Geographer, 33(3): 274-277. Kor, P.S.G., and Teller, J.T. 1986. Canadian Landform Examples- 1: Ouimet Canyon, Ontario- Deep Erosion by Glacial Meltwater. The Canadian Geographer, 30(3): 273-275. Teller, J.T., and Thorleifson, L.H. 1983. The Lake Agassiz- Lake Superior Connection. In Glacial Lake Agassiz. Edited by J.T. Teller and L. Clayton. The Geological Association of Canada, St. John�s, Newfoundland. pp. 261-290. Teller, J.T., Thorleifson, L.H., Dredge, L.A., Hobbs, H.C., and Schreiner, B.T. 1983. Maximum Extent and Major Features of Lake Agassiz. In Glacial Lake Agassiz. Edited by J.T. Teller and L. Clayton. The Geological Association of Canada, St. John�s, Newfoundland. pp. 43-45. Trenhaile, A.S. 1990. The Geomorphology of Canada. Oxford University Press, Don Mills, ON. Wilkins, C. 1994. A Deep Geological Puzzle: Exactly how Ontario�s spectacular Ouimet Canyon was formed remains an intriguing mystery. Canadian Geographic, 114(6): 52-61.