Victoria EarthCache Series #1: Drumlin over yonder EarthCache

To complete the requirements to log this cache, you may require a simple handheld compass if your GPS does not have this capability.

The coordinates listed above will take you to a viewpoint to observe a rather large drumlin surrounded by water in the ocean to your east.  Boaters will probably recognize this island and its very long sand bar that creates a navigational hazard due to its extended shallow depth.  Understanding the history that has taken place here will help you to understand why the sand bar is the size and shape that it is.

Drumlins are streamlined hills formed during the advancement of glaciers. They are like ripples that form under a glacier, sometimes caused by deposits of sand and gravel left downstream of harder material (in this case the drumlin will have a solid rock core in the stoss end); other times they can be caused by deposits of sand and gravel left by large water flows underneath the glacier (there will be no solid core in this case). This island drumlin is likely of the second type, and is made up of sands and gravels of the Quadra Formation that accumulated in front of an advancing glacier during what is called the Fraser Glaciation (25,000 to 10,000 years ago).

The Coast Mountains north of Vancouver were the origin of the glaciers that flowed past here and over the site that is now called Victoria. Drumlins are always arranged parallel to the direction of ice movement, so you can see from observing this island drumlin, which direction the ice was moving as it advanced.

Drumlins have the distinct shape of an inverted spoon. The Stoss end is the steeper slope and the Lee end is the more gradual slope. The Stoss slope always faces the direction of glacial came from (the upstream end) and the lee slope is the downstream end.  If this drumlin was on land, it would look very much like it did when the glacier created it. But it is located in the ocean and has been subject to erosion.

To log this cache, you must do the following:

1. Go to the listed coordinates. They will take you to the summit of Bear Hill which is a CRD Regional Park.  http://www.crd.bc.ca/parks/documents/bear_hill_map.pdf  Please follow all park use policies:  www.crd.bc.ca/parks. Take a picture of you with your GPS at the listed coordinates with the drumlin in the background and post it in your “found it” log.  The only exception to a photo at this location would be a photo of you, with your GPS, taken from your boat with the island in the background.

THE DRUMLIN IS PRIVATE PROPERTY!!! Do not attempt to go there!!

Through the geocaching messaging system please answer the following questions:

1. Using a compass, tell us which direction the Lee side of this drumlin faces and therefore which direction the glaciers flowed (remember ocean currents have eroded the gradual slope that is normally indicative of the Lee side!).
2. What is the name of the private island that is the drumlin?  You will need ‘local knowledge’ or you can accomplish this by finding a chart of the local waters (online or in paper form).
3. If you do this from Bear Hill (instead of a boat) also post a photo of the scratches and elongated gouges in the rock below your feet… these are “striations” caused when the same glacier that formed the island carved its path over Bear Hill. The ice was rather thick eh?

View of the drumlin from the EarthCache Coords

These gouges (called striations) were carved out by the same glacier that created the drumlin.