1. Answer the following questions briefly:
1. What does weathering mean? What does gradation mean?
22. Name two major types of weathering. Name two processes involved in gradation.
3. Describe how changes of temperature lead to weathering.
WEATHERING AND DENUDATION
Exercises
4. What is exfoliation?
5. How does frost action cause weathering?
6. Name the different processes of chemical weathering
7. What is hydration?
8. Describe the work of plants as agents of weathering
9. Which human activities lead to weathering of rocks?
10. State the effect of weathering.
11. What happens when the river is in its upper course?
12. How is a waterfall formed?
Answers
Answer:
1. Gradational processes Weathering = breakdown of material in place Gradation = leveling of land degradation (erosion) = removal of highs transportation = movement of material aggradation (deposition) = filling in lows Tectonic processes build up of roughen up the earth Gradational forces level off highs and fill in lows ...
2. Denudation is the wearing away of landmass by various agents as water, wind and ice through various processes like weathering, mass movement, erosion and transportation. Name the two processes of gradation. Answer: Two processes are denudation and aggradation.
3. Sudden change in temperature causes fissures in the rocks through which water penetrates to motivate chemical weathering along with sudden contraction and expansion due to change in temperature peels out the upper layer of rock known as exfoliation.
4.Exfoliation involves the removal of the oldest dead skin cells on the skin's outermost surface. Exfoliation is involved in all facials, during microdermabrasion or chemical peels. Exfoliation can be achieved by mechanical or chemical means.
5. Mechanical weathering physically breaks up rock. One example is called frost action or frost shattering. Water gets into cracks and joints in bedrock. When the water freezes it expands and the cracks are opened a little wider.
6.Chemical weathering is what happens when rocks are broken down and chemically altered. Learn about the different types of chemical weathering, including hydrolysis, oxidation, carbonation, acid rain and acids produced by lichens.
7.In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understood
8. Plants protrude their roots through joints in the rocks and as the plant grows, the joints in the rocks get widened. The widening of joints allows water to seep through. Seepage of water may cause chemical weathering or frost action.
9.Weathering is a natural process, but human activities can speed it up. For example, certain kinds of air pollution increase the rate of weathering. Burning coal, natural gas, and petroleum releases chemicals such as nitrogen oxide and sulfur dioxide into the atmosphere.
10.The effects of weathering disintegrate and alter mineral and rocks near or at the earth's surface. This shapes the earth's surface through such processes as wind and rain erosion or cracks caused by freezing and thawing. Each process has a distinct effect on rocks and minerals.
11.As the river moves through the upper course, it cuts downwards. The gradient here is steep and the river channel is narrow. Vertical erosion in this highland part of the river helps to create steep-sided V-shaped valleys, interlocking spurs, rapids, waterfalls and gorges.
12.Waterfall formation is based around the basic principle that there is a watercourse (realize that water is an erosive agent) traversing over different layers of rock each with different rates of erosion. In other words, you have a river or stream flowing over hard rock (where erosion is slow) and also flowing over soft rock
Explanation:
subscribe my channel Siddhi Rawat
Answer:
Gini Uni
Explanation:
Q1) breakdown of material
Gradational processes Weathering = breakdown of material in place Gradation = leveling of land degradation (erosion) = removal o
Q2) Two processes are denudation and aggradation
Q3) Temperture changes can also contribute to mechanical weathering in a process called thermal stress. Changes in temperature cause rock to expand (with heat) and contract (with cold). As this happens over and over again, the structure of the rock weakens. Over time, it crumbles.
Q4) Exfoliation involves the removal of the oldest dead skin cells on the skin's outermost surface. Exfoliation is involved in all facials, during microdermabrasion or chemical peels. Exfoliation can be achieved by mechanical or chemical means.
Q5) One example is called frost action or frost shattering. Water gets into cracks and joints in bedrock. When the water freezes it expands and the cracks are opened a little wider. Over time pieces of rock can split off a rock face and big boulders are broken into smaller rocks and gravel.
Q6) There are different types of chemical weathering processes, such as solution, hydration, hydrolysis, carbonation, oxidation, reduction, and chelation. Some of these reactions occur more easily when the water is slightly acidic
Q7 ) In chemistry hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understood.
Q8) Plants protrude their roots through joints in the rocks and as the plant grows, the joints in the rocks get widened. The widening of joints allows water to seep through. Seepage of water may cause chemical weathering or frost action.
Q9) Mining and quarrying exposes bare rocks on the surface and these get weathered quickly.
...
Following human activities lead to weathering of rocks :
Mining.
Quarrying.
Deforestation
Q10) The effects of weathering disintegrate and alter mineral and rocks near or at the earth's surface. This shapes the earth's surface through such processes as wind and rain erosion or cracks caused by freezing and thawing. Each process has a distinct effect on rocks and minerals.
Q11) In the upper course of a river gradients are steep and river channels are narrow. ... When a river runs over alternating layers of hard and soft rock, rapids and waterfalls may form. Waterfalls commonly form where water rushes down steep hillsides in upland areas and quickly erodes the rocks.
Q12) Waterfalls often form in the upper stages of a river where it flows over different bands of rock. It erodes soft rock more quickly than hard rock and this may lead to the creation of a waterfall. Formation of a waterfall: The soft rock erodes more quickly, undercutting the hard rock.
Happy to help