Katepwa Fluting Field
This cache may not be for everyone, it will take approximately 22 km. of grid road travel. Not all the way to the posted co-ordinates are on a all weather road, the last 6 km of the route may be impassible at times, use your discretion. While you can complete this cache any time of the year, views will be more spectacular when not hindered by snow cover.
Route to GZ from Highway 56
The Lesson:
Fluting is a process of differential weathering and erosion by which an exposed well-jointed coarse-grained rock such as granite or gneiss, develops a corrugated surface of flutes; especially the formation of small-scale ridges and depressions by wave action.
Fluting in glacial geology:
Flutes are narrow, elongated, straight, parallel ridges generally consisting of till, but sometimes composed of sand or silt/clay. Flutes typically reach a height of only a few meters or less, but some may reach heights of 10 meters (~30 ft.), and may extend up to several kilometers in length. Flutes are oriented parallel to the direction of ice movement, and are formed when boulders become lodged on the subglacial floor by basal melting, and can no longer be moved by the passing glacial ice. The glacial ice must then flow around these boulders, creating elongated cavities in the ice parallel to the ice flow. These cavities in the ice are then filled with water-soaked till, which is squeezed up into the cavities as a result of high confining pressures on the glacier bed from the overlying glacial ice. As a glacier recedes, it exposes these long, low ridges of till. These glacial processes give the topography a "fluted" appearance, giving rise to the name flutes. Flutes can often be traced back to single large boulders embedded in the glacial till.
The formation by glacial action of smooth deep gutter like channels or furrows on the stoss side of a rocky hill obstructing the advance of a glacier; the furrows are larger than glacial grooves, and they do not extend around the hill to the lee side. Also, a furrow so formed lineations or streamline grooves and ridges parallel to the direction of ice movement, formed in newly deposited till or older drift. They range in height from a few centimetres to 25 metres, and in length from a few meters to more than 20 km.
Glaciers shape the landscape through the removal and redisposition of surface material in this area. Features created by ice erosion are not common. The Katepwa fluting field is one such feature. The series of long ridges and grooves was created between 20,000 and 15,000 years ago during the last glaciation.
As the ice moved across the land, it scoured and scraped the surface. Here the result was a fluting pattern trending in a Northwest to Southeast direction. This indicates the direction of the ice movement. In the last ice age, as ice and water melted and flowed south, glaciers pushed along the field, leaving in their wake deep grooves that at some points measured 4 -5 meters deep. This area has been developed for farming and cultivation has changed the landscape, making the fluting less visible.
Alluvium is loose clay, silt, sand, or gravel that has been deposited by running water in a stream bed, on a floodplain, in an alluvial fan or beach, or in similar settings. Alluvium is also sometimes called alluvial deposit. Alluvium is typically geologically young and is not consolidated into solid rock.
Subsequently the area was inundated by Glacial Lake Indian Head and the flutings were covered with a blanket of Lake clay sediments. Around this point the clay sediments have been since stripped off by water erosion.
In the last ice age, as ice and water melted and flowed south, glaciers pushed along the field, leaving in their wake deep grooves that at some points measured 4 -5 metres deep. Since glaciation, alluvium has been deposited in the grooves. Also, this area has been developed for farming and constant cultivation has changed the landscape, making the fluting less visible than it once was.
The tasks:
All readings and observations should be taken from the road, pull over to the side, but there is no need to go into the ditch, or onto private property.
1) At the posted co-ordinates, you will be at the bottom of a flute. Take an altitude reading with your GPS device at the bottom, and at the top of both sides. Calculate the depth of the flute.
2) Go to the second reading waypoint, you will be at the bottom of a flute. Take an altitude reading with your GPS device at the bottom, and at the top of both sides. Calculate the depth of the flute.
3) Based on the average of your two readings, and what you have read in the listing, how much alluvium do you think has been deposited in flutes since glaciation?
4) Go to the sign waypoint, send me the years that this location was in operation.
5) From your observations at the waypoints, describe the direction you think the last glacier traveled when it moved across this area. What is the length of the fluting field between the way points?
6) From information found in the listing, why do you think the flutes are visible in this area?
7) Compare what you see at the posted co-ordinates, Flute2 waypoint, and Top of the field waypoint, discribe what you see, and what may have caused any differances.
When you have collected the answers to the questions, send them via " Message this owner " at the top of this page and include the GC code, cache name, the caching names of the cachers in your group, and the answers.
While not required, pictures posted with your log are always welcome, and enjoyed.
After you have sent your answers, you may log this cache, but missing, or incorrect answers will be challenged, and if not resolved, logs will be deleted.
References:
Wikipedia
Qu'Appelle Valley Geolog