Lynde Creek owes its creation to the Lake Simcoe Glacial Lobe, a section of the retreating Wisconsin Glacier. As the glacial lobe retreated northeast, Lake Iroquois was created over what is now Lake Ontario and a section of the surrounding shoreline which included Durham Region from Lake Ontario north to the Oak Ridge Moraine.
Glacial Lake Iroquois was a prehistoric proglacial lake that existed at the end of the last ice age, 12,500 -13,000 years ago. The level of this lake was approximately 30m (100 ft) above the present level of Lake Ontario. This lake was held in place by an ice dam at the Gulf of St. Lawrence and drained at Rome, New York through the Mohawk Valley and Hudson River. As the ice melted and the dam broke, Lake Iroquois was reduced in size very quickly leaving behind a thick sandy beach deposit, now visible north of Taunton Road in the vicinity of the Macedonian Village and the Heber Down Conservation Area. Further east the Rome Sand Plains have several sand ridges that geologists think were formed at this time.
The Lynde Creek Watershed travels south through four distinct geological regions and has a drainage area of 133 square kilometres. These regions encompass the Oak Ridges Moraine including Chalk Lake, the source of the Lynde Creek; Till Plain which starts just south of Myrtle Road to Hw #7 including Brooklin; Lake Iroquois shoreline, an area that encompasses Heber Down Conservation Area; and finally the Glacio-lacustrine Plain.
Logging Requirements:
At the posted coordinates you will find an information sign with the answers to the following questions. Please email me to my profile the answers. DO NOT INCLUDE THE ANSWERS IN YOUR FOUND LOG.
1. Based on the information contained on the sign at the posted coordinates what are the five layers that make up the geological profile of the Lynde Creek watershed?
2. If you are standing at the top of the Oak Ridges Moraine, how many metres above sea level would you find bedrock or Whitby shale?
3. What layer makes up the section known as the Lake Iroquois Shoreline?
4. In which section will you find clay and silt?
5. OPTIONAL: Take a photo of you or your GPS with the Lynde Creek watershed in the background. There are a number of nice spots along the waterfront trail you can get a clear shot, and you might spot some wildlife.
Note: Please send me your answers within 4 days of posting your found log. If there are more then one cacher in your party, include the names in your group. Only one person needs to send me the group answers. No spoiler photo's of the information sign please. Found logs posted without proof you visited the site will be deleted.
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