Lake Travers DeGeer Moraines
On a 2011 September trip to Lake Travers in Algonquin Park (See Exploring Lake Travers in Algonquin Park), one of our objectives was to locate, identify, and photograph the DeGeer Moraines that lie adjacent to the eastern shore of the lake.
DeGeer moraines are formed under water at the face of a retreating glacier. The small parallel moraines result from the seasonal oscillation in the position of the ice face. That is, the ice face moves forward in the winter, creating the rocky ridge, and retreats in the summer. Since the glacier is overall retreating, in general the summer retreats are larger than the winter advances. A good description of the formation of these moraines can be found here: Canadian Landform Inventory Project: Main/DeGeer Moraines.
In the case of Lake Travers, the DeGeer moraines formed as the melt water ponded against the glacier face as the glacier retreated north. The melt water drained southward towards Grand Lake until the glacier retreated sufficiently to open up a lower drainage path to the north and subsequently down the lower Petawawa River. When the drainage to the north opened, the resultant flow washed away a channel through the moraines, this channel corresponding to modern Lake Travers (1).
While we knew where the moraines were located (2), our primary difficulty was that we didn't really know what it was we were looking for. We envisioned an open jackpine forest, perhaps with a ground cover of sweet fern on sand, with gentle, low amplitude, parallel undulations that would be a challenge to photograph. We were wrong on all counts except the last.
Our starting point was the most northerly campsite on the eastern shore of Lake Travers (just south of the big island). This location is at the northern extent of the Lake-Travers-De-Geer-Moraines nature reserve. By bushwhacking south from this location, we would pass down the center of the nature reserve and presumably encounter the moraines perpendicularly. Since it was close to noon, we navigated by simply walking towards the sun, with a compass and gps for backup.
We encountered and noticed our "first" moraine about 90m into the bush, but we didn't immediately recognize it as such. After another several tens of meters more we encountered our next moraine and realized that it was these long ridges of boulders, hiding in the forest debris and moss, that we were looking for. They resembled large, rough stone fences extending east-west through the bush. We encountered five of these before turning back, partly because of the hard going — we came up against a mass of blow downs — and partly because we had found what were looking for.
The moraines that we encountered in the bush are shown in the photos below. The numbers in the photo captions are for location identification. The photo locations are shown on the satellite view at the bottom of this page.
After we realized that the campsite was on a moraine, it also dawned on us that the numerous rocky fingers extending into the lake along the eastern shore were also moraines. However, by then the wind had risen to a level that made it impractical to photograph and map those moraines before heading back to our campsite on the other side of the lake. We were able to photograph them and record their locations on our way out the next day. However, even then the wind was brisk, and it made getting good photographs a challenge.
In spite of the apparent similarity of many of the following photos, they are all of distinct rocky points along the eastern shore of Lake Travers. Each photo was taken at the end of an apparent moraine along the shore so as to determine and record the location of that moraine.
The paragraph on the formation of the Lake Travers DeGeer moraines is speculative on our part; more authoritative sources should be sought.
The DeGeer Moraines of Lake Travers are protected as a named nature reserve. However, while the various nature reserves in Algonquin Park are indicated on the "Canoe Routes Map", they are not explicitly named and adjacent reserves are not separated. They are, however shown separately and named on Jeffrey McMurtie's Algonquin Park Exploration Map. Another good map showing the various nature reserves is the one included with 1998 Algonquin Park Master Plan.
The locations were determined as follows: We geotag all of our photos (although the copies of the photos included on this page have had their geotagging removed for convenience in processing). The geotagging is accomplished by marrying the gps track with the capture time of the photograph as recorded in its exif data. The two cameras that we used were synchronized with gps time within 30 seconds. The software used for marrying the exif data with the gps data (downloaded and saved as a gpx file by OziExplorer) was Photo Mechanic by Camera Bits. To plot the data for the selected photos, the lat / lon pair of each photo was output as a waypoint in a gpx file generated by customizing the text export function in Photo Mechanic. (While this file validates as a gpx file, it is pretty rudimentary.) This file was then used as input to OziExplorer. OziExplorer could then be used to view the photo locations, or to output the data as a slightly more sophisticated gpx file or as a kml file suitable for viewing in Google Earth.
It should be noted that Bob carried the gps. Consequently, for photos taken by Diana, the location data would be off when Bob and Diana were separated. This was not an issue for photos taken along the shoreline from the canoe but was an issue for photos taken while we were bushwhacking. Further the gps was having some difficulties in maintaining satellite reception in the bush. Consequently, the inland photo locations are less reliable than those along the shore.
The "minor moraines" are from the OGS dataset (see bibliography) as displayed on Google Earth.