Department of Ottawa Geological History Earth Sciences (http://www.geoscape.nrcan.gc.ca/ottawa/index_e.php) The oldest rocks in the region are the Precambrian metamorphic rocks, (mainly marble, gneiss and quartzite) and igneous intrusions, (including granite and pegmatite) of the Explore Geoheritage Day Gatineau Hills and some small areas of Carp and Kanata. These rocks are the deeply eroded roots of ancient mountains Sunday, October 24, 2010 that were once as tall as the present-day Himalayas. Between 1.2 and 1.0 billion years ago, sedimentary and volcanic rocks, 10:00am to 3:00pm* originally deposited along the margin of ancient North America, were deformed, metamorphosed, and intruded by magma as a result of collision with another continent. This collision ceased Come join our volunteers from about 1 billion years ago and the mountains began to be slowly eroded and worn away. During the following ~100 million Carleton University’s Department years, we have no rock record, probably because rock was of Earth Sciences and the being removed by erosion rather than being deposited. Ottawa Gatineau Geoheritage In the Paleozoic, between 510 and 440 million years ago, a warm tropical sea flooded the region. (We were near the Project at area parks, heritage equator then!) The oldest Paleozoic rock found in the area is sites and green spaces and learn Cambrian in age, (the Nepean sandstone) and represents an ancient beach. In the Ordovician, an ocean moved onshore how geological processes have and covered this beach so that limestone (reefs) and shale (deep sea sediment) were deposited on top of the sandstones. shaped the local landscape and This ocean advanced and retreated creating a thick layer of provided resources for our use. sedimentary rock. Fossil remains of trilobites, cephalopods, crinoids, corals, snails, and other shelled animals that lived in In the last 2 billion years the ancient coral reefs can be found by the thousands in the the Ottawa Valley has shale and limestone layers in the area. Champlain Lookout, Gatineau There is no record of what happened in the following ~400 been a huge mountain Champlain Bridge Stromatolites million years, as there is no local rock of this age range. Perhaps no rock was deposited, or perhaps it was, and then chain, a tropical beach, Brebeuf Park, Gatineau was eroded away. habitat for large whales, Ottawa Building Stone Walking Tour About 175 million years ago, in the Mesozoic, the Ottawa- Hogs Back Park, Ottawa Bonnechere graben formed when the land surface dropped and buried under 2km of Billings Estate, Ottawa, Randy Bosswell downward between the two major fault zones which form the boundaries of the Ottawa Valley. These ancient faults have ice... Where do the rocks and fossil activities been reactivated over time, and are occasionally active today, in your backyard fit in? Carp Ridge Hike, Kanata releasing crustal stress in the form of earthquakes. Erskine Johnston Public School, Kanata During the Quaternary, great ice sheets, sometimes 2 km thick advanced and retreated several times over the northern half of Mer Bleue Bog, Orleans North America, finally retreating~12,000 years ago . The loose sediments that blanket bedrock in much of the Ottawa- Gatineau area were left behind as these glaciers melted at the end of the Ice Age.
http://www.geoscape.nrcan.gc.ca/ottawa/index_e.php *unless otherwise noted Downtown Ottawa Building Stone Champlain Lookout, Gatineau Park, Billings Estate, Ottawa (*opens 11:00am) Walking Tour (*begins 10:30am) Quebec On Riverside Drive turn onto Pleasant Park Drive, and The buildings of Ottawa's downtown core provide a right again at Cabot, following the signs to the From Ottawa, drive across Champlain Bridge, right museum at the end of the road. Jounalist Randy fascinating look at stone from quarries in Ontario, onto Alexandre Taché and left onto Promenade de la Boswell will speak about Elkanah Billings, the first Quebec, Manitoba and the eastern US. We will Gatineau Parkway into Gatineau Park. Follow the signs Paleontologist with the Geological Survey of Canada, begin at Parliament Hill’s Centennial Flame at and his contribution to our knowledge of ancient life. to Champlain Lookout ~20km from Alexandre Taché. You will also find a display of some of the 1000 new 10:30am. Sites will also include the National War The retaining wall of the lookout is built from species of fossils described by Elkanah including the Memorial, Confederation Square, City Hall and Precambrian rocks common in the park and the unique and important Ediacaran fauna from Lisgar Collegiate. Newfoundland. You will also find volunteers who will Champlain Bridge Stromatolites, information plaques provide an overview of the help you to make “fossil” impressions to take home geological history of the National Capital Area. and learn the special conditions under which fossils Gatineau, Quebec Volunteers will be on hand to talk about the regional are preserved and found. From Ottawa, drive across Champlain Bridge and geology that has shaped the landscape as seen from W. Erskine Johnston Public turn left at the first stop lights on the Gatineau side this location, as well as the geological history of School, Kanata of the Bridge. Follow Rue Lucerne about 100 m from Gatineau Park. Drive west on Queensway/417 past Moodie Drive. the lights,and turn left again into Samuel de Hogs Back Park, Ottawa Take March Rd. exit to Kanata. At lights, continue Champlain parking lot. Walk a few steps riverward to Hogs Back Park is located on the north side of Hogs straight onto Campeau Dr., turning right on Teron the bike path. Turn left on this paved path and walk Rd., left on Beaverbrook, then right on Varley Dr. Back Drive between Riverside and Colonel By Drive. Follow this curving road to W. Erskine Johnston halfway back toward Champlain Bridge. Along the From Carleton's campus walk south along the canal for Public School. Park in a spot near the playground river, you will see a pavement of circular, mounded 10 minutes until you reach Hog's Back Road. The falls structures. The rocks in the school’s backyard are structures called stromatolites, formed 450 million mainly metamorphic rocks with some igneous are on the left. These rocks are from the Cambrian and intrusions. They are part of the Grenville Province years ago during the Ordovician Era, when mats of Ordovician Eras and were formed in a tropical shallow of the Canadian Shield, and are more than 1 billion cyanobacteria living in shallow warm water built water environment. You can see fossils, glacial striae, years old. These basement rocks are among the domed structures by trapping sediment grains into oldest in the National Capital Area, and are a sedimentary structures and also how rocks can be beautiful example of how rocks can be folded and layers. Stromatolites were common in the Early folded and broken up by faults. deformed inside a mountain belt. The rounded Paleozoic as there were no snails to eat the algae; Carp Ridge Hike, Morgan’s shapes of the outcrops and the grooves on surfaces now stromatolites only form in very restricted (*begins 12 noon) are the result of glaciers moving over the surface Grant, Kanata during the last Ice Age. environments, the most famous being in Shark Bay, Take HWY 417 to March Road north, and turn left onto Australia where the water is too salty for snails or Klondike Road. Follow this road to the end and park Mer Bleue Bog, Orleans other algae predators to survive. 12 Take the 417 east to Innes Road exit, turning left/east on Second Line Road. The hike will start here at towards Orleans. Turn right on Anderson Road and Brebeuf Park, Gatineau, Quebec noon. The trail will take you over metamorphic and continue south on Anderson to the top of the second From previous stop, turn right onto Rue Lucerne and igneous rocks of the Precambrian Grenville Province of hill; turn left onto Ridge Road. At the end you will find the board walk interpretive trail. This important turn right at Rue Begin. Go to the end of the street. the Canadian Shield and the overlying Paleozoic The monument represents Jesuit martyr Brebeuf. wetland is a remnant of the Champlain Sea formed Nepean Sandstone. These rocks have been exposed during the retreat of Glaciers some 9500 years ago. Park in a designated area and walk down to the by faulting along the southern margin of the Ottawa This type of ecosystem is commonly found in the boreal forests of northern Canada. river. Ordovician limestone is well exposed along Bonnechere Graben system. the shoreline with abundant corals, cephalopods, The new website for the Ottawa Gatineau Geoheritage Project will be coming on- gastropods, mollusks, brachiopods, bryozoa, trace line in November. Tolearn more about the Project and find more information about For more information visit www.earthsci.carleton.ca interesting geological sites in the National Capital area, fossils and fragments of trilobites.* googleOttawa Gatineau Geoheritage Project in November!