Warning:
This site is not dangerous by itself but you still need be to be vigilant as you are close to cliffs. Please, watch your steps at all times and do not come close to the edge – you DO NOT need to attend the edge of the cliffs to find the answers needed to claim your find.
To claim your find, please answer the following questions:
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What is the key difference between erosion and weathering?
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At the bottom of the cliff, there are multiple caves
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Do you think this caves exist due to an erosion process, or is it because of weathering?
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What type of erosion or weathering would be involved in here?
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How was the material taken away from cliffs?
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Look at the cliffs, the land, your surroundings: based on the reading and your observations, do you see any possible causes for erosion or weathering (beside the one involved in cave creation) ? Name or describe two of these
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Please add a picture of yourself or something personal at GZ in your post.
The Site
Cape Tryon is located on the north (Gulf of St. Lawrence) coast of central Prince Edward Island. The site is on northward facing sea cliffs (comprised of Permian sandstone) that are about 35 m high, with open sea below. Above the site, the tablelands consist of an undulating, cultivated plateau that abuts the sea. The northern exposure of the cliff-face presumably creates a cooler microclimate during the spring than do other exposures.
Cape Tryon is the oldest known cormorant colony in P.E.I., where both Great Cormorants and Double-crested Cormorants regularly nest.
Closeby is the Cape Tryon Lighthouse. The Cape Tryon Lighthouse is a 12.5 metres (40 feet) square, tapered, wooden lighthouse that sits atop a red sandstone cliff to the north of the village of French River, guiding mariners and their vessels along the northern coast of Prince Edward Island between Richmond Bay and New London. The lighthouse was built as an automated light to warn vessels of the shallow water that extends out a considerable distance from shore. It is painted in the traditional white with red accents. Built in 1967, it is the second lighthouse on the site.
Erosion and Weathering
Erosion and weathering are the processes in which the rocks are broken down into fine particles. Erosion is the process in which rock particles are carried away by wind and water. Weathering, on the other hand, degrades the rocks without displacing them. No rock on Earth is hard enough to resist the forces of weathering and erosion.
Weathering and erosion constantly change the rocky landscape of Earth. As it smooths rough, sharp rock surfaces, weathering is often the first step in the production of soils.
Erosion
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust and then transports it to another location where it is deposited. Erosion is distinct from weathering which involves no movement. The Erosion can be:
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physical or mechanical erosion, involving removal of rock or soil as clastic sediment
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chemical erosion, where soil or rock material is removed from an area by dissolution.
While erosion is a natural process, human activities have been effectively stimulating erosion . Eroded sediment or solutes may be transported just a few millimeters, or for thousands of kilometers.
Because of the site, we will focus on coastal erosion.
Coastal erosion is a natural phenomenon that affects the coastal areas around the world. To adequately address its implications on the environment and coastal communities, it is essential to understand its causes and effects and thus become aware of environmental problems.
There are four ways that waves and tides erode the coast:
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Hydraulic action which is when air may become trapped in joints and cracks on a cliff face. When a wave breaks, the trapped air is compressed which weakens the cliff and causes erosion.
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Abrasion is when bits of rock and sand in waves grind down cliff surfaces like sandpaper.
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Attrition occurs when waves smash rocks and pebbles on the shore into each other, and they break and become smoother.
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Solution is caused by acids contained in sea water and will dissolve some types of rock such as chalk and limestone.
There are also 4 main ways that waves and tidal currents transport material away from their original site:
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Solution. Minerals are dissolved in sea water and carried in solution. The load is not visible. Load can come from cliffs made from chalk or limestone, and calcium carbonate is carried along in solution.
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Suspension. Small particles are carried in water, eg silts and clays, which can make the water look cloudy. Currents pick up large amounts of sediment in suspension during a storm, when strong winds generate high energy waves.
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Saltation. Load is bounced along the sea bed, eg small pieces of shingle or large sand grains. Currents cannot keep the larger and heavier sediment afloat for long periods.
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Traction. Pebbles and larger sediment are rolled along the sea bed.
Weathering
Weathering describes the breaking down or dissolving of rocks and minerals on the surface of Earth. Water, ice, acids, salts, plants, animals, and changes in temperature are all agents of weathering. Once a rock has been broken down, a process called erosion transports the bits of rock and mineral away. As it smooths rough, sharp rock surfaces, weathering is often the first step in the production of soils
Weathering is often divided into the processes of mechanical weathering and chemical weathering.
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Mechanical Weathering (or physical weathering), causes rocks to crumble.
Water is often a key agent of mechanical weathering (e.g. Freeze-thaw mechanism) as well as temperatures (e.g. Thermal stress), changes in pressure (sheeting process) or other processes involving clay, salt (haloclasty), plants and animals.
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Chemical Weathering is the process where there's a change in the molecular structure of rocks and soils (ex: carbonation, hydration or hydrolysis), carving caves, weakening, dissolving or rusting stones.
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Biological weathering, in which living or once-living organisms contribute to weathering, can be a part of both processes and can involve Growing Plant Roots, Microbial Activity, Burrowing animals or Human activities.