Located on the Dempster Highway 258.8 kilometres from the Klondike Highway junction, the Ogilvie Ridge viewpoint presents the visitor a stunning, unobstructed easterly view down the valley of the Ogilvie-Peel river system. At the viewpoint the visitor can learn about the geological features of the area by viewing the tables on the interpretive platform. By visiting the viewpoint and studying the tables on the interpretive platform, you can find the answers to the following questions.
1) Glaciers Versus Water: this table describes the evolution of Ogilvie-Peel river system. According to the table, its evolution is a testament to the profound changes imposed by the advance and retreat of Ice Age glaciers.
a) Two million years ago, the ancient Peel River flowed far to the east, draining into the Arctic Ocean by the way of what today would be the Anderson River. The Mackenzie river has also experienced some changes since that time. In which way has the flow of upper Mackenzie changed from the ancient times and where did it drain then?
b) Thirty thousand years ago, the Laurentide Ice Sheet reached its maximum, completely blocking the Peel's easterly flow. Before eventually spilling over a divide, flowing northward and carving out a channel now occupied by a river, its waters backed up and formed a large glacial lake. What is the name of that lake and which river occupies the channel?
c) Later the ice began to melt back from the Richardson and Ogilvie mountains and the Peel had found a new route between the edge of the ice and the Richardsons. When did that happen?
2) Sediments of Centuries Past: far back in Cambrian times, 540 million years ago, the region was part of a continental shelf. At that time, the pale coloured limestones and dolomites of the Ogilvies were being created. They were built up from layer upon layer of shells, coral and other carbonate precipitates in a warm, shallow sea. About 100 million years ago, in Cretaceous times, mountain building began across western North America.
d) Describe how the bedrock of the Eagle Plains was formed?
e) Study the geological map cross-section. What was the direction of the sediment flow?
3) As it has Always Been: rivers of ice sculpted the mountains across the valley and altered the route of the Peel far downstream. But this valley and Eagle Plains never felt a glacier's rasp.
f) Which forces of the nature shaped the eastern edge of Beringia?
g) What are the reasons described that prevent most boaters from travelling the upper Peel?
4) Hydrocarbons in the Plains: like petroleum-rich Prudhoe Bay and the oilfields of Alberta, this region was part of the sedimentary basin that caught the interest of exploration companies. Crews arrived in the winter of 1954. Seismic testing over the next few years led to drilling of the first well, a dry one, in 1957. The second well was much more successful, producing both oil and gas.
h) Over the thirty year drilling history, how many wells yielded significant oil or gas?
i) Because of the lack of roads and the difficult terrain, completing the 300 km long journey from Dawson took the winter cat trains several days. Describe the route taken by those winter cat trains.
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