Welcome to the middle of No-where! Actually you are in the middle of no-where between Mortlach and Moosejaw Saskatchewan. More specifically, you are along the South edge of Pelican Lake, which is also home to the Thunder-creek Heritage Marshes. The Thunder Creek Marshes are a series of prairie wetlands located along Thunder Creek in south central Saskatchewan. Developed by Ducked Unlimited Canada in the early 1990s, the project is one of ten large wetland complexes in Saskatchewan that were developed as wildlife habitat under the Saskatchewan Heritage Marsh Program. Located in the mixed grass prairies of south central Saskatchewan, Thunder Creek occupies a glacial meltwater channel landform which divides the Central Saskatchewan Plains to the north and the Missouri Coteau to the south. The Missouri Coteau, characterized by a high density of small wetland complexes and an expanse of native grasslands, is an important landscape for American migratory waterfowl, shorebirds, songbirds and other wildlife. The Thunder Creek Heritage Marshes include over 4,000 hectares/10,000 acres of wetland habitat on 17 project segments.
This is a very interesting location as it teaches a great lesson in terms of Glacation and the importance of marsh land. I also find it interesting, and I think you will you will too, that we are talking about an area that was formed around 8-6000 years ago when the last glacier, the Laurentide Ice Sheet, retreated, but at the same time, has been recently manipulated by man, as late as the late 1990's, to be able to maintain the surrounding marsh lands. Its not very often that we get it right when we try to manipulate mother nature, but this is one area that has greatly benefited from human intervention while we too are able to benefit in a sustainable way for years to come.
Glacial Till
An advancing ice sheet carries an abundance of rock that was plucked from the underlying bedrock; only a small amount is carried on the surface from mass wasting. The rock/sediment load of alpine glaciers, on the other hand, comes mostly from rocks that have fallen onto the glacier from the valley walls. The various unsorted rock debris and sediment that is carried or later deposited by a glacier is called till. Till particles typically range from clay‐sized to boulder‐sized but can sometimes weigh up to thousands of tons.
As glaciers retreat, they deposit their till loads through various means that transform the landscape. As you drive throughout most of Saskatchewan you will see various examples of Glaciers depositing till and you probably wouldn't think twice about it. The following are three of the more common types of glacial deposits:
Morain:
Moraines may be composed of debris ranging in size from silt-sized glacial flour to large boulders. The debris is typically sub-angular to rounded in shape. Moraines may be on the glacier’s surface or deposited as piles or sheets of debris where the glacier has melted. There are also various types of moraines that include Lateral moraines, Ground Moraines, Rogen Moraines, and Terminal Moraines to name a few.
Outwash:
As a glacier melts, till is released from the ice into the flowing water. The sediments deposited by glacial meltwater are called outwash. Since they have been transported by running water, the outwash deposits are braided, sorted, and layered.
Eskers:
Eskers are long, winding ridges of outwash that were deposited in streams flowing through ice caves and tunnels at the base of the glacier. Generally well sorted and cross‐bedded, esker sands and gravels eventually choke off the waterway.
Wetland Geology
Geology plays a critical role in understanding wetland dynamics. Wetlands are places that are regularly saturated with water, causing the growth of plants that are specifically adapted to living in wet conditions and the development of characteristic soil features. Wetlands are important because they create products and perform vital functions for man. Our richest modern soils originally formed in wetlands that were drained for farming. Valuable resources such as coal and peat are mined from the deposits of ancient and existing wetlands. Existing wetlands perform many economically and ecologically important functions, such as storing floodwaters, removing sediment and chemicals from surface water, replenishing groundwater, maintaining low flows in streams, and providing wildlife habitat. There are three main types of Wetlands:
Topogenous:
These are a type of wetlands that are common in hollows and low spots in the landscape where the water is allowed to accumulate. The shape and form of the land determine where the wetland forms. This is the most common type of wetland, especially in areas that do not have excessive precipitation.
Soligenous:
This type of wetland also lies in the hollows of the landscape, but the rocks below the surface stop the water from penetrating. This causes the water to move sideways over the rock into springs. The springs put the water into the wetland in the hollows, which causes the water to change its chemistry due to the make-up of the rocks.
Floodplain:
Low parts of valleys tend to allow the water to collect in the flat sides near the water source. During heavy rains and snow melts, the floodwater overflows from the stream or river and travels across the wide flat plains. This enriches the soil and allows for ideal agricultural development.
The location is off the #1 Highway directly North of the Besant Park Campground. There is signage and it is accessible via East and West bound. Grid road is not recommended when wet and probably not good in winter. To register this find, you need to answers the following questions. You will need to visit both stages to be able to aquire the answers to the questions. Do not post your answers with your log . . . please email them to me directly:
Stage #1
1. The bedwaters of The Thunder Creek are delivered from what Saskatchewan Lake? How was it delivered?
2, How was Thunder Creek manipulated to enhance the wetlands along the creek?
Stage #2
1. What type, or types, of glacial till deposit do you find at this? How is the till being utilized by the local RM (Royal Municipality)?
2. What type of wetland do you find at this stage? List three ways that the wetland aids local residents.
3. Based on the location of the Till deposit, what direction was the Glacier moving?
4. As an optional task, please post a picture of yourself or party at ground zero. We love seeing people enjoying our caches!
Please note that this is an Earthcache, which means there is not a physical cache at ground zero. For more information on Earch caches, please visit www.geocaching.com or www.earthcache.org. For more information about wetlands and their conservation, please visit www.Ducksunlimited.ca
http://www.irrigationsaskatchewan.com/SIPA/tti_v2-chap3.pdf
http://www.cliffsnotes.com/sciences/geology/glaciers-and-glaciation/glacial-deposits
http://www.ducks.ca/learn-about-wetlands/what-wetland/
http://en.wikipedia.org/wiki/Wetland