This Earthcache is accessible via boat, paddleboard, kayak, or canoe. While the area is beautiful it can be quite dangerous. Always pay attention to wind and weather patterns before heading out and make sure you have all of the appropriate safety equipment with you at all times. Recommended launch for your watercraft is from Charles Daley Park, however limited parking can also be found on South Service Road. You do not need to exit your watercraft to answer the questions. You do need to physically visit GZ to log your visit. Approaching from Fourth Ave is not recommended.
Today, the GPA43 group was out paddling and we came across a rather pronounced example of undercutting and erosion on the banks of Canada Island. This Earthcache will explain whaqt undercutting is, and why it is important to take note of it.
PLEASE do not actually touch the undercutting! Let's preserve the island as much as possible, as it seems to be a habitat for a number of animals and birds.
Under Cutting
Under cutting is an erosional process, caused by successive waves, at all intensities, washing against the shoreline. Undercutting caused by rivers, glaciers, or ocean waves creates over-steepened slopes, which are prone to failure.The more intense the pounding of the waves, the quicker the undercutting will occur, leading to mass wasting. The type of material that is being undercut also has a significant part to play in how quickly an area will experience undercutting - fine, loose particles are more prone to undercutting as they are less stable and will wash away wityh even the smallest waves. As the shoreline is undercut deeper and deeper, the ability to support the shoreline and debris above it is weakened, eventually leading to a slump or a shoreline fail, where the weight of the debris falls forward, towards the lake. Undercuts can be recognized by exposed roots, below the soils surface, or an overhanging cliff of rock or soil.
After enjoying a lovely paddle from the recommended put-in Coordinates, you should now be paddling around a small island, named Canada Island. This is where you will make your observations from. You do NOT need to exit your vessel to gather the answers. Please send me the answers using the Geocaching Message Center or send me an email with your answers to the above questions, then go ahead and log this earthcache. You do not need to wait for my response to log. I will contact you if there are any issues with your answers. Feel free to post additional pictures as well, but please do not post your answers with your log.
1) At GZ, you should see a very prominent area of undercutting. Approximately how wide and high is the undercut?
2) Paddle around the island and see if you notice any other examples of undercutting. How do you know this was caused by undercutting?
3) Do you see any other signs of erosion on the island that are not caused by undercutting? Hypothesize what they could be caused by?
4) Based on the location of the island and the location of the undercutting, why do you think that this particular location is as undercut as it is? Do you think that the undercutting here is made worse by human activity? Do you think the type of soil is contibuting to the undercutting, or slowing the process slightly?
5) In your log, please include a photo of yourself with Canada island in the background.