Sifting Through the
Soil:
Determining London’s Local Soils
Prepared by:
Danielle Ward
519-661-2500 ext. 2844
dward@london.ca
www.london.ca/teacher
Before you Begin:
The City of London has various resources available to you throughout this lesson
including informational videos and webpages. If you have any questions about the
material before or after the lesson please do not hesitate to contact us. If you have an
idea for another lesson, or have connected this lesson to curriculum we have not,
please let us know. We are always looking for feedback, ideas for improvement and
new lessons.
Resources:
Resources for this lesson include the activities attached, and City of London soils maps.
Other resources may also be available such as soil tests.
Field Trip Resources:
Jaffa Environmental Education Centre
Grade 7:
1. Interactions in the Forest: Students investigate the roles and interactions of
producers, consumers, and decomposers within a forest ecosystem. Students
study the relationships between living organisms and the abiotic factors affecting
them.
Vansittart Woods Environmental Education Centre
Grade 7:
1. The Changes we Make: Students will role play in groups interested in buying
Vansittart woods EEC, and deciding how they would use the area. With the use
of maps and air photos, they will design a plan and predict how this will impact
(positive or negative) the existing natural environments, local communities, and
surrounding land. Documentation of observations during field work using
cameras, GPS, binoculars, recording may support or change their land use
choice.
Feedback:
Finished this lesson?
We would love to hear how it went and any ideas for improvements, activities or
additional lessons! Send us a quick email with your grade and unit that you used this
lesson for with any comments, questions or suggestions.
Thank you for using The Teaching Toolkit and taking the time to help us continue to
develop and improve the resources!
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Curriculum Connections:
Grade 7:
Geography- Physical Patterns in a Changing World
A1. Analyse challenges and opportunities presented by the physical environment
and ways in which people have responded to them.
A2. Use the geographic inquiry process to investigate the impact of natural
events and/or human activities that change the physical environment, exploring
the impact from a geological perspective.
A3. Demonstrate an understanding of significant patterns in Earth’s physical
features and of some natural processes and human activities that create and
change those features.
Geography- Natural Resources around the World: Use and Sustainability
B1: Analyse aspects of the extraction/harvesting and use of natural resources in
different regions of the world, and assess ways of preserving these resources.
B2: Use the geographic inquiry process to investigate issues related to the
impact of the extraction/harvesting and or use of natural resources around the
world from a geographic perspective.
B3: Demonstrate an understanding of the sources and use of different types of
natural resources and some of the effects of the extraction/harvesting and use of
these resources.
Grade 7:
Writing
Overall expectations
1. Generate, gather, and organize ideas and information to write for an intended
purpose and audience.
2. Draft and revise their writing using a variety of informational, literary, and graphic
forms and stylistic elements appropriate for the purpose and audience.
3. Use editing, proofreading, publishing skills and strategies, and knowledge of
language conventions, to correct errors, refine expression, and present their work
effectively.
Oral Communication
Overall expectations:
1. Listen in order to understand and respond appropriately in a variety of situations
for a variety of purposes.
2. Use speaking skills and strategies appropriately to communicate with different
audiences for a variety of purposes.
Grade 8:
Geography- Global Settlement Patterns and Sustainability
A1. Analyse significant interrelationships between Earth’s physical features and
processes and human settlement patterns, and ways in which the physical
environment and issues of sustainability may affect settlement in the future.
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A2. Use the geographic inquiry process to investigate these issues related to the
interrelationship between human settlement and sustainability from a geographic
perspective.
A3. Demonstrate and understanding of significant patterns and trends related to
human settlement and ways in which human settlement affects the environment.
Geography- Global inequalities: Economic Development and Quality of Life
B1. Analyse some interrelationships among factors that contribute to global
inequalities, with a focus on inequalities in quality of life, and assess various
responses to these inequalities.
B2. Use geographic inquiry process to investigate issues related to global
development and quality of life from a geographic perspective.
B3. Demonstrate an understanding of significant patterns in and factors affecting
economic development and quality of life in different regions of the world.
Grade 8:
Oral Communication
Overall Expectations:
1. Listen in order to understand and respond appropriately in a variety of situations
for a variety of purposes.
2. Use speaking skills and strategies appropriately to communicate with different
audiences for a variety of purposes.
Writing
Overall Expectations:
1. Generate, gather and organize ideas and information to write for an intended
purpose and audience.
2. Draft and revise their writing, using a variety of informational, literary, and graphic
forms and stylistic elements appropriate for the purpose and audience.
3. Use editing, proofreading, publishing skills and strategies, and knowledge of
language conventions, to correct errors, refine expression, and present their work
effectively.
Lesson Resources:
Below are the resources developed by the City of London to help enhance the lesson. It
should be noted that the resources do not have to be used; however they were
developed specifically to help enhance the local nature of each lesson.
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Resource 1: Soil Quiz
Soil Formation Quiz
Answer the following questions below after listening to the slideshow:
1. Name all of the soil forming factors mentioned in the slideshow.
2. What does parent material provide to soil?
3. How does climate influence soil formation?
4. What landscape features influence soil development?
5. Why is vegetation important in soil formation?
6. How do humans influence soil?
7. Name 3 examples of ways humans have influenced soil around the world
8. Other than an earthworm name two other soil organisms.
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Resource 1: Soil Quiz-Answers
1. Name all of the soil forming factors mentioned in the slideshow\
Parent rocks and sediments, climate, landscape, vegetation, soil
organisms, time, man.
2. What does parent material provide to soil?
Texture, pH, and nutrients from minerals
3. How does climate influence soil formation?
Through temperature and precipitation events
4. What landscape features influence soil development?
Steep slopes, valley bottoms, flood plains, low lying plains
5. Why is vegetation important in soil formation?
Acids released by roots help in the breakdown of the rock, supply organic
matter to the soil, also aids in covering and rooting the soil in place to
prevent erosion
6. How do humans influence soil?
We degrade soil through constant use
7. Name 3 examples of ways humans have influenced soil around the world
Cutting down trees in the rainforest, removing vegetation from slopes, and
using man-made fertilizers, OTHER EXAMPLES ARE WELCOMED
8. Other than an earthworm name two other soil organisms.
Ants, millipedes, centipedes, potato bugs, beetles, etc. OTHER EXAMPLES
ARE WELCOMED
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Resource 2: Soil Map of London
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Resource 3: Soil Research Activity
Digging up the Dirt on London’s Local Soils
Within a group of 4-6 people, choose a local soil from London’s soil map. In class
research the soil to determine its characteristics, referencing the questions listed below;
1. What is the parent material for your chosen soil?
2. Where does the parent material originate from/ what type of rock formation is the
parent material (sedimentary, metamorphic, or igneous)?
3. What is the texture of your soil like (course, smooth, silky, gritty)? Try and find
the identifying words to define the texture of your soil.
4. What is the average pH of your soil? Is it generally more basic or acidic?
5. How do you think the parent material broke down to create the soil? Think about
all of the geological processes that have occurred over time in Canada
(glaciation, upheaving, glacial retreat, water feature development).
6. How has climate influenced the development of your soil? Has temperature or
precipitation aided in its formation?
7. Looking at the landscape in London and comparing to where your group’s
chosen soil is on the London soil map, do you think the landscape has anything
to do with where your soil formed and where it is now?
8. How do you think vegetation contributed to the formation of your soil?
Remember, some soil types consist of more vegetation than others.
9. Do you think local vegetation such as grass and native plant coverage has
allowed your soil to stay locally in London? If your soil was light and grainy could
it have been moved elsewhere?
10. What role do you think soil organisms played in the development of your soil?
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11. How old do you think your soil is (young, relatively young, older, the oldest soil
type)?
12. How do you think time has affected the composition and position on the map of
your soil?
13. How does your soil and mankind interact? Is the chosen soil used for agriculture
or used to make concrete or other building materials?
14. How do you think mankind may have interacted with the soil locally? Do you think
your group’s chosen soil will be largely affected by mankind in the future?
After researching and answering the following questions, develop a creative
presentation with your group to teach the class about the features of your local soil.
You can use a variety of pictures, videos, and displays. Be sure to acknowledge the
pros and cons of your soil within the presentation. At the end of your presentation
you should be prepared for your classmates’ questions about the soil.
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Resource 4: Something to Think About
The Black Blizzard
Use this sheet to reflect upon any thoughts during the movie. Keep in mind during the
film that Canada‘s prairie provinces also became dust bowls during this time and still
have not recovered. The soil in these areas is degraded to the point that it can no longer
grow weeds or simple grasses.
Some questions to help fuel thought reflection:
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Do you think the dust bowl could have been prevented?
Do you think the climate shift was the only reason for the black blizzards?
Why do you the farmers had no “cover plants”?
Do you think soil is inexhaustible, like the government did?
How would you go about fixing the dust bowl today?
Do you think fixing the dust bowl is a manageable task? (Hint: Think of cost and
time.)
How do you think the loss of fertile soils impacted the biodiversity of the area?
Do you think something like this could happen in London?
If it could happen in London, how much would it impact your daily life?
.
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Resource 5: Soil Hand Test
Characterizing Your Soil
By identifying the type of soil you are determining what lies beneath your feet after
millions of years of different processes. The type of soil in an area helps determine
several things; two of which are water drainage and fertility. In present day, soil samples
of an area are often taken to determine drainage, fertility, level of contamination, and
overall composition. These important factors are often used to assess the overall
sustainability of an area. For example; before building a major housing project,
contractors and engineers may sample the soil to determine if the soil will shift under
weight, what type of drainage they should expect in periods of high precipitation, as well
as whether or not they have to bring in top soil to grow grass and other plants.
Your homework is to determine what type of soil you have in your backyard. If you live
in a condo or apartment building simply find a grassy area near your building and dig up
a little bit of soil to complete the assignment. The type of classification used in this
specific assignment is called a “hand test.” Follow the chart below to determine what
type of soil you have. Write a small paragraph explaining how you came to the
conclusion about what type of soil you had in your backyard and be prepared to present
it to the class.
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Resource 6: Characterizing Soil using the Soil Triangle
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Characterizing Local Soils
Soil texture depends on its composition and the relative portions of clay, sand,
and silt. In sedimentology, clay is defined as particles of earth between 1 micrometer
and 3.9 micrometers in diameter. Silt is defined as particles between 3.9 micrometers,
and 62.5 micrometers in diameter. Sand has the largest defined particles ranging from
62.5 micrometers to 2 millimeters in size.
Below is a soil triangle which is used to determine types of soils based on their
composition. The percentages of the side of the triangle are arranged symmetrically. On
the left the numbers correspond to the percentage of clay, on the right the numbers
correspond the percentage of silt, and on the bottom the numbers correspond to the
percentage of sand. To classify a soil sample, you find the intersection of the three lines
that correspond the three portions. On the chart the percentages will add up to 100%.
Example: Classify a soil sample that is 30% clay, 15% silt, and 55% sand.
1. First, locate 30% on the clay axis and draw a line horizontally left to right
2. Locate 15% on the silt axis, and draw a line diagonally down to the left.
3. Finally, locate 55% on the sand axis, and draw a line going up diagonally to
the left. The intersection should be in Sandy Clay Loam.
Apply the method above to determine the type of the following soil compositions.
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1. While digging in his backyard Sam found some soil of a different colour that he
has never seen before, upon examining it he knows that it is 60% clay, 20% silt,
and 20% sand. What type of soil does Sam have in his backyard?
2. An engineer at the City of London is looking at designing a new bridge over the
Thames River, he knows that on one side of the bank the soil composition is 20%
clay, and 60% silt. And the other bank is 10% clay and 60% sand. What soil
types are on either side of the river.
3. A farmer in London is having issues with his crops, so he decided to determine
the type of soil in his field. He knows the soil has a composition of 50% clay, and
that he has some silt content but not more than 35%. What type of soil does this
farmer have?
4. While building a sandcastle along Lake Huron, Victoria noticed that the sand she
was using worked better than the sand along Lake Erie. She noticed that it had a
lower sand content (less than 100%) then the sand along Lake Erie. And it had
some clay in it (less than 20%). What two types of sand could it have been?
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Resource 7: Mapping Local Soil Resources
Mapping the Classes of Soil Types in London
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Lesson Notes:
Slide 1:
Introduce the lesson;. Explain that discovering information about London’s soil is very
important as soil supports a lot of the daily needs we have today. For example, soil
provides habitat for many organisms while also providing nutrients to plants that are part
of our daily diet.
Slide 2: Soil
Soil is like the Earth’s skin, it covers the majority of the earth’s surfaces. Even the
oceans have their own forms of soil. Soil is an essential function in enhancing life on
earth. It provides nutrients to plants, helps with drainage, maintains structural stability,
and also provides habitats for thousands of different organisms.
Different types of soils are formed from different contributors. These contributors make
each type of soil different and allow each soil to offer many different benefits, while also
limiting their abilities. Soils offer a variety of beneficial functions to us, however, they
can also be a hindrance. Different types of soils have different types of functions, some
have higher nutrient levels, other have better drainage, all of the soils characteristics
come from its original contributors during its formation.
Slide 3: Contributors to Soil Formation
There are seven contributors to the formation of soil. Each contributor alters the content
or characteristics of the soil greatly. Ask the students if the can think of any possible
contributors to early soil formation. If there are no ideas, ask them how they think soil
was made and where it could have possibly come from.
Slide 4: Parent Material
Parent material refers to the rock base that the soil originated from thousands of years
ago. Explain to the students that over thousands of years various cycles of rainfall,
snow, and freeze and thaw cycles help to break down rock.
Ask students how they think the effects of rainfall, snow, and freeze and thaw cycles
affect rock and how these processes may change the geological composition or
landscape of these areas.
- Explain to them that these factors weaken the rock’s overall structure, by
allowing water to enter cracks, and then during the freeze and thaw cycles each
winter and spring, the cracks grow larger and eventually lead to pieces breaking
off.
Explain to the students that the parent material/rock is the main factor responsible for
the texture of the soil (for example, sandstone makes sand, and shale makes clay) and
is also important in determining the pH of the soil and how rich it will be in nutrients.
Explain that a rock’s acidity and nutrient content level have to do with the amount of
minerals in each rock.
Slide 5: Climate
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Ask students what they think the two main climatic influences are that aid in the
development of soil. Explain that fluctuating temperatures increase the breakdown of
underlying rock and also increase the rate of nutrient release into the soil. Precipitation
events such as rain and snow melt also aid in rock break down to form soil. Examples of
how climate affects the formation of soil include:
- In hot wet climates, soils tend to be deep and rich in nutrients.
- In cold artic areas, soils are thin and poorly developed.
Ask the students to identify a region with each type of soil, ask them if they think the
climate in London plays a factor in the development of its soil. Ask them how the climate
impacts local soil.
Slide 6: Landscape
Ask the students if they know what a landscape is and choose one student to explain it.
Landscapes generally impact the depth and overall thickness of soils. For example,
steep slopes have shallow soils because soil is easily washed down hillsides in events
often known as mudslides. Ask students if they can picture the side of a mountain and if
it has thick soil on it? Explain that flat land such as at the bottom of a valley, as well as
flood plains, or other low lying areas have deeper richer soils. Ask students why they
think this is? Explain that it is mainly due to the displacement of soil from one place,
particularly steep slopes, and its movement to a lower lying area, such as a valley,
where it no longer has anywhere to move to.
Slide 7: Vegetation
Ask the students how they think vegetation affects the formation of soil. Explain that
vegetation aids in creating soils by releasing acid compounds into the soil which helps
breakdown bedrock. Once the rocks are broken down into smaller materials the
vegetation is able to supply its remains as a source of organic material to help enhance
the soil.
Ask the students if vegetation aids in soil development in any other way. Ask them to
think about the structure of vegetation and how it is rooted in the soil. Ask them if they
think soil will move more with something rooting it into the ground or “covering it”
compared to a bare area such as the dessert. Ask them to keep the importance of
vegetation in mind as it plays a key role in preserving soils.
Slide 8: Soil Organisms
Soil Organisms are those that live within the soil, while they do not contribute to the
breakdown of the material associated with primary soils, their movement and recycling
of organic matter within the soil help create pores which allow air circulation and add
nutrients. The way in which organisms dig or burrow into the soil allow air to penetrate
the top layer and help break down the organic material in the middle and deeper layers.
Explain to students that soil containing more organisms means it has a higher nutrient
and organic matter base.
Slide 9: Time
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Explain to students that every second of everyday, soil is being formed. However, the
soil that we rely on to grow plants and create construction materials from developed
thousands of years ago. Explain to them that, specifically in Canada when the glaciers
retreated thousands of years ago they left rich soil deposits from when they originally
moved down from the arctic, these soil can still be found in Ontario and even in London.
Explain that soil degrades over time (loses nutrients to erosion, loses nutrients to plants)
and since it is constantly renewing itself, it appears to be a renewable resource.
However, if the soil in an area is over used or significantly degraded it can impact the
region severely for many years.
Slide 10: Man
Explain to students that man also plays a significant impact in the development of soils
as well as its destruction. Soils play an important part in our history, present, and future.
Farmers rely on the constant renewal of soil to help give nutrients to their plants which
in turn we eat to survive. Soil can be managed well through many different practices
such as crop rotation (rotating what crops go in what areas, such as planting corn in an
area where beans were planted last year - beans fix nitrogen, and corn requires
nitrogen for growth) and no-till (allowing the soil to keep a small cover on top of it to
prevent wind and rain erosion). There are a lot of areas in the world where soils have
been damaged beyond repair. For example, cutting down trees and removing them from
the rainforest reduces the organic matter present in the underlying soil, reducing its
overall nutrient levels. Cultivation or removal of vegetation along slopes increase
erosion of soil as without a cover plant or roots to help stabilize it the soil will move
down the steep slope. The final large scale issue is the use of man-made fertilizers
which degrade natural nutrient levels as well as soil organisms.
Slide 11: Quick Quiz
Ask students to fill out the Soil Quiz- resource 1 in the “Sifting through the Soil” toolkit.
Ask them to then pass their sheet to the right for their peers to mark. Refer to the
answer sheet provided in the resources for the appropriate answers.
Slide 12: MOVIE -Black Blizzard
Explain to the students that the degradation of soil due to human affects has major
effects on the biodiversity of the soil, the nutrient levels of the soil, and the ability of soil
to be rooted into the ground, rather than swept away by the wind. Explain to students
that during the 1930’s, also known as the “dirty thirties,” the prairie regions of Canada
and the United States experienced the after effects of mass soil degradation. During the
video, ask students to write down their thoughts or ideas about the “dust bowl” on
Resource 4: “Something to think about” worksheet provided.
Slide 13: Soil types
Give each student Resource 2: Soil Map of London.
Explain to the students that local soil is important to study to determine how sustainable
the area is. For example, in earlier years, places were often settled based on the lands
ability to provide. If the soil had no nutrients, it could not provide food for the livestock or
for the family and therefore the family would move to an area with more fertile soil.
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London is an area that has a variety of different soils. There are many farmers and
backyard gardeners who rely on the soil to encourage food, grass and flower growth
each year. Ask the student if they can name one of the 5 soils in London.
Slide 14: ACTIVITY
Hand out Resource 3:
Separate the class into groups of 4-6 people, ask them to refer to Resource 3: Soil
Research Activity-Digging up the Dirt on London’s Local Soils. Give each group a type
of soil found in London and ask them to use the internet to research the soil, and try and
answer all of the questions found on their worksheet. After answering all the questions
they can on their worksheet ask them to develop a creative presentation to help teach
the class about soil. Explain that they may use pictures, videos, displays, and even
develop their own worksheets for the class to use during their presentation. Be sure to
tell the students to focus on explaining the pros and cons of the local soil they were
assigned and how the local soil affects London’s landscape and economy (farmingconstruction materials).
Slide 15: HOMEWORK ACTIVITY
Give the students Resources 5 and 6 for homework. Explain to them that it is important
to characterize local soils, as it allows us to plan for sustainability in terms of which soils
have better drainage (we would build houses on), or which soils are most fertile (we
would have farms on, etc). Explain to them that there are two ways to characterize soil.
The first is a hand test; the second is using a soil triangle. Tell them in the homework
activities they will learn how to use both. For the soil hand test ask them to go outside in
their backyard or if they are in an apartment building, in an area close to their building
and dig up a small sample of dirt. Once completed, proceed to Resource 5: Soil Hand
Test. Following the steps on the chart students can determine what type of soil they
have in their backyard. Ask them to complete Resource 6: Characterizing Soil using the
Soil triangle, following the instructions on the sheet using the provided examples and
questions.
Slide 16: Mapping Soil Types
After the completion of Resource 5: Soil Hand Test, ask each student to read out their
results. Record the results with the aid of a volunteer on chart paper. Also ask the
students to identify the street on which they live (do not need the house number). After
all of the students report their soil type, hand out Resource 7: Mapping Local Soil
Resources. This resource will be specific to your school’s boundaries. Hand out a blank
copy of the map to each student; ask them to plot a point on each street that their
classmates live on. Then draw an area around that point and shade it in based on the
type of soil they found. Make sure that similar soil types have the same colour. After
they shade in each students findings, ask the students to blend the areas if there are
any differences in soils. For example if there is a white space between Classmate A and
Classmate B’s houses and they have the same soil type, fill in the gap with the soil type
in that areas colour. If the classmates have two different soil types find the halfway point
between the two and colour one half classmate B’s color and the other half classmates
A’s colour.
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Slide 17: Report on your Findings
Give the students one hour to write a page or more about why certain soils are located
in certain areas and why their soil sample is a specific type. Ask them to look at their
map and draw conclusions from it. For example, what is the most common soil, what it
the least common soil, what types of soil would be nutrient rich, which would be nutrient
poor? Are there areas where there is only one type of soil that is found? Ask them to
think about what challenges people may face with their soil type on their properties such
as flooding, poor plant growth, erosion, etc. Also ask them to determine if the ways the
soils are being managed in London are sustainable. Ask them to explain the
consequences of careless degrading processes on soils. Ask them to compare the
possibilities of soil degradation to the documentary “Black Blizzard”.
Slide 18: What did you think?
Provide the students a minute to talk about what they thought about the lesson and its
resources. Ask them what they would have done and how they would have done it, or if
they found one part of the lesson to be more interesting than other parts. Through
asking students what they think about the lesson the City of London can continue to
make more appropriate and intriguing lessons for school groups.
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Additional Resources
Basic Information about local soils:
• Alluvium:
– A loose unconsolidated (not stuck together) soil
– Developed from the erosion of existing sediments in non-marine
environments
– Contains silt, clay, sand, and gravel
– A very young soil
– Can contain valuable ores such as gold, platinum, and a variety of
gemstones
• Clay:
– Fine grained natural rock or soil material that combines one or more clay
minerals with organic matter
– Clay forms over long periods of time from the chemical weathering or
rocks
– Clay is typically associated with depositional environments such as lakes
and marine basins.
– There are two types of Clay
• Primary: form as residual deposits in soil and remain at the site of
formation
• Secondary clays that have been transported from their original
location by water erosion and are deposited in a new sedimentary
deposits
• Organics
– Soil that is loose and porous
– Developed from plant and animal tissues in various stages of breakdown
– Contains various forms of minerals and nutrients
– Associated with areas of high decomposition such as bogs, marshes or
forest floors.
– The youngest soil
• Silt
– Silt is granular material of a size somewhere between sand and clay
– Mineral origin is quartz and feldspar
– Silt is easily transported in water or other liquids and is fine enough to be
carried long distances in the air in the form of dust
• Sand
– Sand is a naturally occurring granular material composed of finely divided
rock and mineral particles
– Loose
– The most common constituent of sand in inland continental settings is
silica, usually in the form of quartz. Sand found near oceans is formed
from calcium carbonate that has been created over the past half billion
years by various forms of life like coral and shellfish
– An old soil type
• Gravel
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– Gravel is composed of unconsolidated rock fragments that have a general
particle size range and include size classes from granule to boulder-sized
fragments
– Gravel deposits are a common geological feature being formed as a result
of the weathering and erosion of rocks.
– The actions of rivers and waves tend to pile gravel in large accumulations,
resulting in gravel becoming compacted and concreted into the
sedimentary rock called conglomerate.
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