Nipissing Geohistory François Castilloux

The landscape of the Nipissing region is particular. Explorers, voyageurs and settlers had a hard time to describe it. The landscape is not uniform and varies significantly between flat and rocky lands. For us, we have to think about the rocky

forests of Field and River Valley, the flat fields of Verner and Millerand, the bushy lands of Sturgeon Falls and Cache Bay, the creeks of Lavigne and Monetville, the sharp cliffs of Beaucage and Yellek, the steep slopes of Duchesnay and North Bay, the bumpy meadows of Corbeil and Bonfield, etc. As we can see, the landscape variation of our region is clearly visible. Moreover, this kind of landscape was well documented by the first Europeans navigating on Lake Nipissing. Samuel de Champlain described the region as “an unpleasant country, full of pines, birches and a few oaks, very rocky and in many places rather hilly”, but near Lake Nipissing he appreciated some “fine ponds and a number of beautiful meadows, with very fine prairies”. After Samuel de Champlain, more adventurers have also noticed the particular landscape of our region. In 1856, the surveyor Albert Salter drew a very long survey line that crosses our region to Lake Superior. He drew what we call today the “Salter Baseline” and kept an account of his observation. He felt that Samuel de Champlain’s description was right. According to him, the landscape around Lake Nipissing is generally “rugged and broken”, but varies at some locations such as “The land at its entrance into Lake Nipissing is low and swampy, consisting on both sides of open prairie”. In 1857, the geologist Alexander Murray explored the area to survey its potential development. He quickly noticed the landscape variation and reported “While the coast [of Lake Nipissing] presents this wild and desolate appearance, there are many spots not very remote from it where the character of the country is much less forbidding [...] when settlement shall at some future time reach the shore of the Lake.” Since the Europeans came in the Nipissing region, many left similar description and the landscape variation, as we saw, didn’t go unnoticed. Furthermore, many of these testimonies give importance to geology, and this, with a lot of reason. Geology affects the human experience and economic activities. The landscape has indeed greatly

influence the history of the Nipissing region and the development of our communities. West Nipissing needs to explore further the geological factors that shaped its past. This history column will therefore explore our past with a geological approach. The Nipissing region has visibly a lot of landscape variations and some people wonder why. Lake Nipissing is the key to this question. In fact, Lake Nipissing is part of a geological system which binds the lake to the Ottawa River. To understand the landscape around Lake Nipissing, we have to first understand the past of the Ottawa River. When the Canadian Shield was formed millions of years ago, some underground faults contorted the landscape to produce what is today the Ottawa River, Lake Nipissing and its waterways. These underground faults are called “Mattawa” and “Petawawa” and, like many other faults, they produced the geological phenomenon called “graben”. In this case, the Mattawa and Petawawa faults have produced the “Ottawa River Graben”. The shape of a graben is particular. It looks like a big and long corridor between two elevated plateaux. These plateaux are called “horst” and, because of their elevation, they produced a steep slope going down to the lower ground of the graben. These slopes are called “escarpments”. Regarding the Ottawa River Graben, the water of the river flows in the graben and the horsts are the rift valley bordering both side of the river. The ground of the graben is flat whereas the ground of the horst is mostly rocky and hilly. When the Ottawa River Graben was formed millions of years ago, it has deformed a large territory around the river reaching Lake Nipissing and beyond. Although the lake is located far from the Ottawa River, this graben has contributed to the formation of Lake Nipissing and its waterways. According to a geological report of the Department of Mines and Northern Affairs (S. Lumber: 1971), the Nipissing region also has a graben which is called “Nipissing Graben”. In fact, the Nipissing Graben is a small extension of the Ottawa River Graben. The Ottawa River Graben goes on a northerly direction from Pembroke to Lake Timiskaming and is crossed by two horizontal faults in Mattawa. These faults are called “Nipissing” and “Crystal Falls” and produced the Nipissing Graben which starts in Mattawa and stretches horizontally under Lake Nipissing and its waterways to disappear West after Warren and the 81st longitude. In our case, the water of Lake Nipissing and the Mattawa and French River flows in most part of the graben. Like

the Ottawa River Graben, the Nipissing Graben has two horsts, this time, bordering the North and South side of the lake. The horst on the North side is notably visible such as the geo-satellite map shows. This horst contorted the landscape making a long horizontal escarpment from Mattawa to Warren. This escarpment is still very visible today and many will recognize the following examples. The escarpment on Highway 64 from Sturgeon Falls to Field, the one on Highway 575 from Verner to Field and on Highway 11 North of North Bay and also the escarpments where are located Duchesnay Falls, Thibault Hill, Wallace Heights, etc. And, we should not forget the sharp cliffs bordering the North side of Highway 17 especially near Beaucage and Yellek. This escarpment forces the water to slide down into Lake Nipissing and its waterways. To some extent, it seems to have determined the location and shape of Lake Nipissing and its waterways. The Ottawa River Graben and the Nipissing Graben not only affected the landscape of our region, but also the ecosystem and living species inhabiting it. The geology of Lake Nipissing and the Nipissing Graben are complex and have greatly influenced the environment such as the flora, the fauna and also human activities. The environment affects human activities, the location of populations, the characteristics of communities and even economic activities. Economic activities on a horst are indeed very different from the ones on a graben. A horst and a graben offers two different environment regarding the relief, the type of soil, natural resources, water access, etc. The horst on the North side of Lake Nipissing is an important element of West Nipissing. It needs to be studied in order to understand well the history of our region. The history of West Nipissing is interesting because it covers a territory on this horst and the Nipissing graben. The best examples are the flat landscape of Verner and the rocky forests of Field.

In fact, Field, River Valley, Crystal Falls and Kipling are located on the horst and therefore on hilly and rocky lands close to 250 m above sea level whereas Sturgeon Falls, Cache Bay, Verner and Lavigne are located on the graben and therefore on flat lands close to 200 m above sea level. This explains why each community experienced a unique kind of development. To better understand the past of West Nipissing, we also have to consider and explore geological factors through time. This approach is called “geohistory”. The geology and the environment of Lake Nipissing have greatly influenced economic activities through years. We must think of, for example, the fur trade at Sturgeon River House, the tree cutting at Field and River Valley, the pulp and paper mills in Sturgeon Falls and Cache Bay, the farmland of Verner and Lavigne. The Nipissing geohistory is impressive and cover a landscape with a lot of variations. All communities have an interesting geohistory and their study is a monumental task. The geohistory answers many questions about the past of our region. Questions such as: Why in 1850 the Nipissing and Dokis Fist Nations choose the current locations for their reserve? Why the CPR was built on the North side of Lake Nipissing and not South? Why some communities specialized in farming and others in lumbering or the service sector? These are all very interesting questions indeed. Their answer enlightens our past and will be found in my future columns.