Friction and Dynamics of Rock Avalanches Travelling on Glaciers
Rationale
The study of rock avalanches travelling on glaciers or glaciated areas has centred around interpreting data collected from case studies throughout history. Looking at this data can confirm that, in general, rock avalanches travelling on glaciers have a reduced coefficient of friction compared to rock on rock avalanches. The decreased resistance contributes to a higher velocity and further distance travelled. The precise reason for this behaviour is the subject of the research paper; it explains how and why the dynamics of rock avalanches on glaciers are different and creates a model that describes the specific contact between a rock landslide and a glacier.
Research into the friction and dynamics of rocks collapsing onto glaciers is particularly interesting at a point in time where rising global temperatures are melting glaciated areas and affecting the frequency of rock landslides. In addition, younger mountain ranges are more prone to earthquakes, as well as being bigger. (have a tendency to be higher, and subject to more seismic and tectonic activity, meaning that) research into the mechanics(dynamics) of rock landslides on glaciers is particularly apt. The aim of the research paper is to create a new model that effectively examines the mechanics and dynamics of rock avalanches on glacial surfaces. The difference between this research and previous work done in the same area, is that this model aims to account for the layer of melted ice between the two surfaces that is formed during landslides, and to identify a relationship between the coefficient of friction, the speed, and distance travelled.
Method
The initial part of the resea...
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... in multiple areas. Although not the main aim of the research, the findings could easily be used to estimate risk and severity of landslides in glaciated areas. A future direction for this research also points to extraterrestrial investigation, especially where satellite images can indicate certain characteristics of apparent landslides on Mars. The research could help to confirm or deny the possibility that ice may have once existed on Mars.
In terms of future work relating to friction specifically, it is mentioned there is the possibility of a fine layer of mud would result from the movement along the glacier. Mud would have a more viscous properties than the present ice/water combination, and might require further investigation. The present model also doesn’t consider the friction that occurs as a result of rocks hitting one another or breaking apart.
Whether zipping along a winding trail, flying through the open flats, or powering up a steep hill snowmachines and the rider need to use physics to stay in control of the machine and themselves. The main compenents are the track, engine, skis and riding.
From the figure above, it is also easy to see that the kinetic friction remains almost constant for a range of speeds. This kinetic friction is the force which slows the skiers down after they start moving.
A good description of a glacier is given by Jim Wickwire in his book “Addicted to Danger.” In it he says, “A glacier is not a fixed, solid thing. It flows like a river, with currents, some parts smooth, others rough” (Wickwire, 1998, p. 1). This happens to go along with Webster’s definition, in that a glacier must be moving, either because of gravity or because it’s spreading out underneath itself due to additional accumulations. (Meeriam-Webster, 2000, p. 493).
Traveling north on an Indian trail, the first sign of the area’s cataclysmic past would have appeared out of place from the rolling hills typical of the Western Pennsylvanian landscape. Peering down into a valley over 400 feet deep, the mighty gorge was littered with enormous boulders, framing the Slippery Rock Creek. These relict boulders of rock types foreign to the area are known as “glacial erratics” and are indicative of the strength of the encroaching glacier. As defined by the National Snow and Ice Data Center, “Glacial erratics are stones and rocks that were transported by a glacier, and then left behind after the glacier melted. Erratics can be carried for hundreds of kilometers, and can range in size from pebbles to large boulders.
Often, the effects of Mountain top Removal are disastrous, the wildlife habitat is damaged and vegetation loss usually leads to numerous floods and landslides. When explosives are used, fly rock, ...
Capps, D., Clague, J.J., Pelto, B., Pelto, M. “Rising ELA and Expanding Proglacial Lakes Lead to Initiation of Rapid Retreat of Brady Glacier, Alaska.” 69th Eastern Snow Conference. Nichols, 2012. Web. 9. Feb. 2014.
The glaciers have been through a minimum of four glacial periods. They’ve been through the Little Ice age, which commenced around 4,000 years ago. Marks of retreating glacier ice are seen in the rock-strewn and sculpted peaks valleys. The land and bodies of water that the retreating ice has created a new display of animal and plant communities.
Many of us have gotten rock chips, but how many of us understand how those pesky rocks hit our windshield? A common misconception is that the car in front of us throws rocks "backward" and hits the following car's windshield. A rolling tire cannot throw a rock backwards. A tire is a rolling object, thus every point along the tire is moving forwards. There is no force going in a backwards direction. Only direction part of a rolling object can go is a combination of up or down, and forward.
Firstly, the landscape around would be dramatically eroded. Whereas a glacier pushes out of the way objects in its path, and erodes the surrounding area through a combination of ablation, plucking and freeze-thaw, the glacier itself commonly hides the features it creates, but when the glacier melts, features such as cirques, horns, arêtes, hanging valleys and waterfalls can be seen. Also, the melt water would itself cut a small v-shape in the base of the U-shaped valley created by the glacier. The stones in the river, and deposition would cause this. Lateral and terminal moraines would also be created after the glacier deposits some of the rocks and dirt that it will have picked up as it moves.
"Snow Storms: What's a Blizzard." Forces of Nature: TQ 2000. Web. 3 Mar. 2014. .
To begin with, the landing of the snow on the road caused many damages to them. This was because the levels on which the roads were raised were in different proportions. This, therefore, prevented lack of flow to be experienced on the roads. Moreover, the cracks that were observed on the roads came about because of the difference in the temperatures of the country.
Living in Bangladesh, we have seen quite disastrous mudslides from the past few years. Mudslide is also called a landslide or a land slip. It is a downward mass movement of earth or rock on unstable slopes, including many forms resulting from differences in rock structure, coherence of material involved, degree of slope, amount of included water, extent of natural or artificial undercutting at the base of the slope, relative rate of movement, and relative quantity of material involved. There are numerous facts that can cause a mudslide and there are also numerous effects that it can cause us.
The 6.7 magnitude earthquake was felt throughout most of southern California and as far away as Utah and Mexico with a max acceleration of 1.0g in several different areas and the highest at Tarzana with a recorded value of 1.8g. The earthquake also deformed over 1500 square miles of the Earth’s crust, forcing the surface upward in a dome shape. The Susana Mountains sustained the most soil deformation with an uplift of around 15cm causing numerous rockslides, blocking many roadways. Soil liquefaction was observed in the Simi Valley area and other parts of the Los Angeles Basin. After all the term oil ended the preliminary cost estimate of damage was between 15 and 20 billion U.S. dollars. Today, Geologists remain to search for thrust faults throughout the southern California area by using a 3 dimensional modeling system to view folds and upli...
U.S. Geological Survey. Worldwide Overview of Large Landslides of the 20th and 21st Centuries. 6 December 2010. 3 February 2011 .