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Try to imagine the ice sheet several kilometres thick that blanketed this region 10,000 years ago. Pushed by gravity and pressures from within, the glaciers inched forward scouring the earth beneath them. The landforms you will see are a product of that movement: a landscape changed forever by a tremendous, powerful force.
This process is far from over. Present-day forces continue working to modify this natural environment.
What's An Esker?
An esker is a glacial landform. Eskers are believed to be created during a glacier's retreat. Meltwater flows inside tunnels within or beneath the glacier, depositing sediments (boulders, gravel, sand) as it flows. The tunnels within the ice gradually fill up with sediments. As the glacier retreats, the sediment within these ice tunnels is left behind, forming ridges. The word esker comes from the old Irish word for “ridge.”
Eskers left by streams at the bottom of glaciers are called subglacial eskers. These eskers tend to be continuous ridges with a consistent, unbroken form and stratified layers of sediment. When the stream ran through the glacier, rather than beneath it, the sediments become disrupted as the glacier melts and retreats. The eskers that result are known as englacial eskers. Their form is more broken, and the sediments are not as neatly stratified.
Eskers are interesting and useful for several reasons. Their size, shape, and composition can give us clues about the speed and direction of a glacier's retreat. They are also good aquifers – their composition is highly porous, so they can hold large quantities of water. The layers of sand and gravel also act as a huge filter, so the water from eskers is often very clean. Eskers can be quarried for rock, gravel, and sand. Because they are often elevated, eskers have been long been used as roads.
Eskers Provincial Park
Eskers Provincial Park is a day-use park located 40 km northwest of Prince George. Encompassing 3,979 hectares of gently rolling terrain and many small lakes, the park conserves a portion of the 40 km long Stuart River Eskers Complex. These unique land forms, for which the park is named, are long sinuous gravel ridges. They were created when sand and gravel were deposited in the meltwater channels of ancient glaciers that once blanketed this northern region. Visitors can enjoy walking and hiking, canoeing, fishing, nature study and wildlife viewing. In the winter the summer hiking trails are turned into an excellent network for snow-shoeing and cross-country skiing enthusiasts. A 3 km beginners loop is located just off the Pine Marsh parking area. For an additional challenge and exercise, skiers can enjoy the 6 km trail to Kathie Lake.
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You may log your find before you hear back from me, but please make sure you send your responses to me at the same time as you log the find. You must meet all requirements to log this as a find! If you work on the Earthcache in a group, each account logging the find should email their own original responses to me.
Question #1
you think this was an englacial or a subglacial esker? Why?
Question #2
At the Posted Coordinates take an altitude reading.
Question #3
what evidence can be seen, that supports that this is an Esker?
Describe what Evidence you see, Terrain, Shape Surrounding area ETC.
Photo's are welcome and encouraged, but not mandatory for
logging this Earth Cache
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