types of weathering presentation

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Middle school Earth and space science - NGSS

Course: middle school earth and space science - ngss   >   unit 4, weathering and erosion.

• Understand: weathering and erosion

Key points:

• The movement of water can create and modify features on Earth’s surface. This happens through weathering, erosion, and deposition.
• Mechanical weathering is the creation of sediment through physical means. For example, a stream can dislodge soil particles from its banks.
• Chemical weathering is the creation of sediment through chemical means. For example, acid rain can react with rocks, dissolving them.
• Erosion occurs when water transports sediment from one place to another. For example, a river can carry mud downstream. In general, water has more erosional power when it flows faster and has more volume.
• Deposition (also called sedimentation ) occurs when water drops sediment in a new location. For example, ocean waves can deposit sand on a beach.

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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.

Earth Science, Geology, Geography, Physical Geography

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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. No rock on Earth is hard enough to resist the forces of weathering and erosion. Together, these processes carved landmarks such as the Grand Canyon , in the U.S. state of Arizona. This massive canyon is 446 kilometers (277 miles) long, as much as 29 kilometers (18 miles) wide, and 1.6 kilometers (one mile) deep.

Weathering and erosion constantly change the rocky landscape of Earth. Weathering wears away exposed surfaces over time. The length of exposure often contributes to how vulnerable a rock is to weathering. Rocks, such as lavas , that are quickly buried beneath other rocks are less vulnerable to weathering and erosion than rocks that are exposed to agents such as wind and water.

As it smooths rough, sharp rock surfaces, weathering is often the first step in the production of soils . Tiny bits of weathered minerals mix with plants, animal remains , fungi, bacteria, and other organisms. A single type of weathered rock often produces in fertile soil, while weathered materials from a collection of rocks is richer in mineral diversity and contributes to more fertile soil. Soils types associated with a mixture of weathered rock include glacial till , loess , and alluvial sediments .

Weathering is often divided into the processes of mechanical weathering and chemical weathering . Biological weathering , in which living or once-living organisms contribute to weathering, can be a part of both processes.

Mechanical Weathering 

Mechanical weathering, also called physical weathering and disaggregation , causes rocks to crumble. Water, in either liquid or solid form, is often a key agent of mechanical weathering. For instance, liquid water can seep into cracks and crevices in rock. If temperatures drop low enough, the water will freeze . When water freezes, it expands . The ice then works as a wedge . It slowly widens the cracks and splits the rock. When ice melts, liquid water performs the act of erosion by carrying away the tiny rock fragments lost in the split. This specific process (the freeze-thaw cycle) is called frost weathering or cryofracturing .

Temperature 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. Rocky desert landscapes are particularly vulnerable to thermal stress. The outer layer of desert rocks undergo repeated stress as the temperature changes from day to night. Eventually, outer layers flake off in thin sheets, a process called exfoliation . Exfoliation contributes to the formation of  bornhardts , one of the most dramatic features in landscapes formed by weathering and erosion. Bornhardts are tall, domed, isolated rocks often found in tropical areas. Sugarloaf Mountain, an iconic landmark in Rio de Janeiro, Brazil, is a bornhardt.

Changes in pressure can also contribute to exfoliation due to weathering. In a process called unloading, overlying materials are removed. The underlying rocks, released from overlying pressure, can then expand. As the rock surface expands, it becomes vulnerable to fracturing in a process called sheeting .

Another type of mechanical weathering occurs when clay or other materials near rock absorb water. Clay, more porous than rock, can swell with water, weathering the surrounding, harder rock. Salt also works to weather rock in a process called haloclasty . Saltwater sometimes gets into the cracks and pores of rock. If the saltwater evaporates , salt crystals are left behind. As the crystals grow, they put pressure on the rock, slowly breaking it apart. Honeycomb weathering is associated with haloclasty. As its name implies, honeycomb weathering describes rock formations with hundreds or even thousands of pits formed by the growth of salt crystals. Honeycomb weathering is common in coastal areas, where sea sprays constantly force rocks to interact with salts.

Haloclasty is not limited to coastal landscapes. Salt upwelling , the geologic process in which underground salt domes expand, can contribute to weathering of the overlying rock. Structures in the ancient city of Petra, Jordan, were made unstable and often collapsed due to salt upwelling from the ground below.

Plants and animals can be agents of mechanical weathering. The seed of a tree may sprout in soil that has collected in a cracked rock. As the roots grow, they widen the cracks, eventually breaking the rock into pieces. Over time, trees can break apart even large rocks. Even small plants, such as mosses, can enlarge tiny cracks as they grow. Animals that tunnel underground, such as moles and prairie dogs, also work to break apart rock and soil. Other animals dig and trample rock aboveground, causing rock to slowly crumble. 

Chemical Weathering

Chemical weathering changes the molecular structure of rocks and soil. For instance, carbon dioxide from the air or soil sometimes combines with water in a process called carbonation . This produces a weak acid, called carbonic acid , that can dissolve rock. Carbonic acid is especially effective at dissolving limestone . When carbonic acid seeps through limestone underground, it can open up huge cracks or hollow out vast networks of caves . Carlsbad Caverns National Park, in the U.S. state of New Mexico, includes more than 119 limestone caves created by weathering and erosion. The largest is called the Big Room. With an area of about 33,210 square meters (357,469 square feet), the Big Room is the size of six football fields.

Sometimes, chemical weathering dissolves large portions of limestone or other rock on the surface of Earth to form a landscape called karst . In these areas, the surface rock is pockmarked with holes, sinkholes , and caves. One of the world’s most spectacular examples of karst is Shilin, or the Stone Forest, near Kunming, China. Hundreds of slender, sharp towers of weathered limestone rise from the landscape.

Another type of chemical weathering works on rocks that contain iron. These rocks turn to rust in a process called oxidation . Rust is a compound created by the interaction of oxygen and iron in the presence of water. As rust expands, it weakens rock and helps break it apart.

Hydration is a form of chemical weathering in which the chemical bonds of the mineral are changed as it interacts with water. One instance of hydration occurs as the mineral anhydrite reacts with groundwater . The water transforms anhydrite into gypsum , one of the most common minerals on Earth.

Another familiar form of chemical weathering is hydrolysis . In the process of hydrolysis, a new solution (a mixture of two or more substances) is formed as chemicals in rock interact with water. In many rocks, for example, sodium minerals interact with water to form a saltwater solution.

Hydration and hydrolysis contribute to flared slopes , another dramatic example of a landscape formed by weathering and erosion. Flared slopes are concave rock formations sometimes nicknamed “wave rocks.” Their c-shape is largely a result of subsurface weathering, in which hydration and hydrolysis wear away rocks beneath the landscape’s surface.

Living or once-living organisms can also be agents of chemical weathering. The decaying remains of plants and some fungi form carbonic acid, which can weaken and dissolve rock. Some bacteria can weather rock in order to access nutrients such as magnesium or potassium. Clay minerals, including quartz , are among the most common byproducts of chemical weathering. Clays make up about 40 percent of the chemicals in all sedimentary rocks on Earth.

Weathering and People

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 . When these chemicals combine with sunlight and moisture, they change into acids. They then fall back to Earth as acid rain . Acid rain rapidly weathers limestone, marble , and other kinds of stone. The effects of acid rain can often be seen on gravestones , making names and other inscriptions impossible to read. Acid rain has also damaged many historic buildings and monuments . For example, at 71 meters (233 feet) tall, the Leshan Giant Buddha at Mount Emei, China is the world’s largest statue of the Buddha. It was carved 1,300 years ago and sat unharmed for centuries. An innovative drainage system mitigates the natural process of erosion. But in recent years, acid rain has turned the statue’s nose black and made some of its hair crumble and fall.

Spheroidal Weathering

Spheroidal weathering is a form of chemical weathering that occurs when a rectangular block is weathered from three sides at the corners and from two sides along its edges. It is also called “onion skin” weathering.

Weathered Mountains

The Appalachian Mountains in eastern North America once towered more than 9,000 meters (30,000 feet) high—taller than Mount Everest! Over millions of years, weathering and erosion have worn them down. Today, the highest Appalachian peak reaches just 2,037 meters (6,684 feet) high.

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April 24, 2024

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Related Resources

Teach Earth Science

Science Partnership of the East Bay

The Weathering of Rocks and Minerals This unit contains resources about chemical and physical weathering of rocks. The product of weathering is sediment that can form sedimentary rocks.

Workshop Presentations

PowerPoint Click to download the MS Powerpoint file (9.6 Mbytes).

PDF. Click to view or download the presentation in PDF (1.3 Mbytes).

HTML . Click to view the presentation in html..

Online lecture Click here to view a streaming lecture. (~24 minutes)

Instructional Case

The Weathering Instructional Case (IC) consists of a series of five lessons and formative assessments that focus on the physical and chemical weathering of rocks and minerals. This IC was written by a team of middle school science teachers in the Integrated Middle School Science (IMSS) Partnership funded by the National Science Foundation. The documents for this IC are available as PDF's for printing and as Microsoft Word documents so that teachers can adapt them for use in their classrooms.

Overview. Click to download an overview of the Weathering Instructional Case. IC Overview PDF

Teacher Background . Click to download a primer for teachers on mechanical and physical weathering of rocks and minerals. PDF

Glossary. Click to download a glossary of scientific terms with definitions and explanations from a scientist and from the perspective of a student. PDF

Unit Timeline. Click to download a Unit Timeline that includes unit objectives and vocabulary. Timeline PDF

Lesson 1 Introduction to Weathering. In this lesson, the teacher will assess the students’ prior knowledge on weathering and erosion using the Page Keeley probe, “Mountain Age”. This probe allows the teacher to assess misconceptions and start the lesson sequence with a “Friendly Talk” probe where students will build their group and scientific process skills. Students will receive an introduction to the Claim-Evidence-Reasoning (CER) protocol and learn how to construct scientific explanations based on evidence and reasoning.

Teacher Lesson. PDF Word Document

• Student Activity Sheet. PDF Word Document
• Student Probe. PDF
• Teacher Notes on Probe. PDF

Lesson 2 Mechanical Weathering - Salt and Chalk Lab. Students will create a simple model of mechanical weathering using colored gypsum sidewalk chalk and salt. The salt, as the agent of abrasion, slowly weathers the sidewalk chalk. Because of the color of the chalk, students can visualize the weathering taking place. Students engage in the practice of modeling and use the model to construct explanations on the phenomenon of mechanical weathering. Teacher Lesson PDF Word Document

• Student Activity Sheet PDF Word Document

Lesson 3 Types of Weathering. After engaging in a pre-assessment probe and an inquiry-based activity, the students will now be able to place the information and vocabulary into context with a card sort. Students will be able to identify and recognize the important factors that affect the rates of weathering. Students will also be able to differentiate between mechanical and chemical weathering.

• Teacher Lesson PDF Word Document
• Student Exit Ticket PDF Word Document
• Classroom PowerPoint presentation PowerPoint Document 6.3 Mbytes
• Template for card sort activity PDF PowerPoint Document

Lesson 4 Effervescent Antacid Weathering. Students will now explore chemical weathering and analyze dissolution rates of effervescent tables. Students will then explore the practice of planning and carrying out investigations. Students will explore the effect of temperature on dissolution rates using different temperatures of water.

Lesson 5 Weathering Competition. Students will culminate this instructional case with in an inquiry-based “Weathering Competition” in which student groups must choose weathering agents to reduce the mass of their rock and justify their choices (hypothesis testing). Different groups will present their data, analyze class data and determine the most effective weathering agents (following the C-E-R format).

Other Classroom Activities

Frost Wedging. This simple classroom activity models frost wedging that breaks rocks at the Earth's surface when water freezes. PDF Word Document

Biological Activity. This simple classroom activity models how tree roots can break rocks as they grow. PDF Word Document

Oxidation. This simple classroom activity models the oxidation of iron to form iron oxides. Oxidation is an important chemical weathering process. PDF Word Document

Online Video and Media Resources

The Forest and the Soil Cycle This video reviews the basics of soils and looks at the cycle of nutrients in a forest. WHRO

The Rock Cycle This interactive rock cycle explains the role of the weathering of rocks. Annenberg Learner.

Useful Websites

USDA Soils www.nrcs.usda.gov/wps/portal/nrcs/site/soils/home/ T his USDA site is the main entry point for information on soils .

USDA Soil Education www.nrcs.usda.gov/wps/portal/nrcs/main/soils/edu/ This USDA site has education materials about soils including lesson plans and other instructional materials.

NRCS photo library photogallery.nrcs.usda.gov/res/sites/photogallery/ This National Resources Conservation Services site is a photo library of images including agriculture and soils.

NGSS Disciplinary Core Ideas

Grade 2 ESS2.A: Earth Materials and Systems. Wind and water can change the shape of the land. (2-ESS2-1)

ESS2.C: The Roles of Water in Earth's Surface Processes. Water is found in the ocean, rivers, lakes, and ponds. Water exists as solid ice and in liquid form. (2-ESS2-3)

Grade 4 ESS2.A: Earth Materials and Systems. Rainfall helps to shape the land and affects the types of living things found in a region. Water, ice, wind, living organisms, and gravity break rocks, soils, and sediments into smaller particles and move them around. (4-ESS2-1)

ESS2.E: Biogeology. Living things affect the physical characteristics of their regions. (4-ESS2-1)

Grade 5 ESS2.A: Earth Materials and Systems. Earth's major systems are the geosphere (solid and molten rock, soil, and sediments), the hydrosphere (water and ice), the atmosphere (air), and the biosphere (living things, including humans). These systems interact in multiple ways to affect Earth's surface materials and processes. The ocean supports a variety of ecosystems and organisms, shapes landforms, and influences climate. Winds and clouds in the atmosphere interact with the landforms to determine patterns of weather. (5-ESS2-1)

ESS2.C: The Roles of Water in Earth's Surface Processes. Nearly all of Earth's available water is in the ocean. Most fresh water is in glaciers or underground; only a tiny fraction is in streams, lakes, wetlands, and the atmosphere. (5-ESS2-2)

Middle School ESS2.A: Earth's Materials and Systems. All Earth processes are the result of energy flowing and matter cycling within and among the planetÕs systems. This energy is derived from the sun and Earth's hot interior. The energy that flows and matter that cycles produce chemical and physical changes in Earth's materials and living organisms. (MS-ESS2-1)

ESS2.C: The Roles of Water in Earth's Surface Processes. Water's movements - both on the land and underground - cause weathering and erosion, which change the land's surface features and create underground formations. (MS-ESS2-2)

High School ESS2.A: Earth Materials and Systems. The geological record shows that changes to global and regional climate can be caused by interactions among changes in the sun's energy output or Earth's orbit, tectonic events, ocean circulation, volcanic activity, glaciers, vegetation, and human activities. These changes can occur on a variety of time scales from sudden (e.g., volcanic ash clouds) to intermediate (ice ages) to very long-term tectonic cycles. (HS-ESS2-4)

ESS2.C: The Roles of Water in Earth's Surface Processes. The abundance of liquid water on Earth's surface and its unique combination of physical and chemical properties are central to the planetÕs dynamics. These properties include water's exceptional capacity to absorb, store, and release large amounts of energy, transmit sunlight, expand upon freezing, dissolve and transport materials, and lower the viscosities and melting points of rocks. (HS-ESS2-5)  

Common Scientific Misconceptions

The atmosphere, hydrosphere, lithosphere, and biosphere do not cause changes in one another; these systems operate independently on Earth.

All bed rock is solid, non porous material.

Hazards are random in both time and place.

Human activities cannot affect geological processes like river floods and mass wasting.

Soil must have always been in its present form

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Teach Earth Science staff include CSUEB faculty and staff from ACOE.

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What are the different types of weathering?

Freeze-Thaw Most rocks are tough. However, a tiny amount of water can cause them to break. When water seeps into cracks and freezes, it then expands. This powerful force can increase the size of cracks. Over time the repeated freeze-thaw action of water can break rocks apart. Eventually, pieces of rock break off, creating scree .

The image below shows the impact of freeze-thaw on a rock in Iceland.

Evidence of freeze-thaw weathering

Exfoliation or Onion Skin Weathering   This type of erosion is common in warm areas. As the sun shines on rocks during the day, it causes them to expand. During the night, the rock contracts due to the colder temperature. Over time this continued process causes small pieces of surface rock to flake off.

The image below shows a close-up of onion skin weathering .

Onion skin weathering

Chemical Weathering Chemical weathering causes an alteration to the chemical composition of the rock due to a reaction. Slightly acidic water can dissolve rock. An example of this would be slightly acidic rain changing the chemical composition of limestone to form a limestone pavement. This occurs on the surface and along the joints and bedding planes of limestone. You can also see evidence of this in buildings made from limestone.

The image below shows limestone that has been chemically weathered. The resulting formation is known as a limestone pavement. You can learn more about these in the limestone area of the site.

Evidence of chemical weathering on this area of limestone pavement

Biological Weathering   Biological weathering is the effect of living things. For example, as the roots of a tree extend into the ground, they can prise rocks apart. Ivy growing up on the side of a building can cause bricks to loosen. It also occurs on a much smaller scale through lichen and moss.

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Types of Weathering.

Published by Adrian Allen Modified over 5 years ago

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Presentation on theme: "Types of Weathering."— Presentation transcript:

Weathering.

SOL 5.7 Weathering

Chapter 5.1 Weathering.

Weathering The breakdown of the materials of Earth’s crust into smaller pieces. It can happen through physical or chemical means and through natural and.

Science 6 Study Pack #8. Today’s Goals…  I can explain what weathering is.  I can identify different causes of weathering.

Weathering and Erosion

World Geography Unit 1: Physical Geography Land and Water Forms. Physical and Chemical Weathering.

Weathering and Soils Practice Test. QUESTION: What kind of weathering is represented by the following picture?

Aim: What is weathering ? I. Weathering – the breakup of rock due to exposure to the atmosphere. A. Erosion – is the removal and transport of earth materials.

Types of Weathering Mechanical Chemical.

Soil Formation By :Reynaldo Thomas. Formation of Soil  Soil is an accumulation of tiny particles of rock which are formed when rocks are weathered. 

Weathering Notes Weathering: Breaking of rocks into Piece - Sediment.

Weathering. I can…. Identify the layers of the earth Describe how landforms can be changed by weathering and erosion Explain how water can change landforms.

1. ____ process that can break rocks and minerals into smaller pieces. 2. ________ weathering is the process of breaking down rocks by chemical reactions.

Learning Outcomes: 1.To be able to understand the terms Weathering and Erosion 2.To be able to understand and describe the different types of weathering.

Science: 6.10B Science: 6.10B Rocks and How They Form.

Weathering. Weathering is the process where rock is dissolved, worn away or broken down into smaller and smaller pieces. BREAKS rocks into different shapes.

 Weathering is the process by which rocks break down and change  Mechanical  Chemical.

Weathering and Erosion. Weathering is the breaking down of Earth’s surface into smaller pieces. EROSION is the process that picks up and carries away.

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Weathering. Earth Science – Ms. Bray. Weathering and Soil Formation. Objectives Define mechanical and chemical weathering. Discuss agents of weathering. Give examples of each type of weathering. . Two Important Types of Weathering. C hemical weathering

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Presentation Transcript

Weathering Earth Science – Ms. Bray

Weathering and Soil Formation Objectives • Define mechanical and chemical weathering. • Discuss agents of weathering. • Give examples of each type of weathering.

Two Important Types of Weathering Chemical weathering • Rock changes composition and becomes a different type of rock. Mechanical weathering • Breaks rock into smaller pieces by using physical processes

Chemical Weathering • Rocks are decomposed, dissolved or loosened by chemical processes to form residual materials • Chemical reactions break down the bonds holding the rocks together, causing them to fall apart, forming smaller and smaller pieces.

Chemical Weathering • The most common types of chemical weathering are: • Oxidation • Hydrolysis • Carbonation

Oxidation • Oxidation takes place when oxygen combines with other elements in rocks to form new types of rock. • These new substances are usually much softer, and thus easier for other forces to break apart.

Oxidation • In this image you can see rust starting to form on the left side of the rock. • This is due to oxidation, which is when the iron in rocks mixes with oxygen and creates rust.

Hydrolysis • Hydrolysis occurs whenwater combines with the substances in rocksto form new types of substances, which are softer than the original rock types. • HYDRO means WATER • So, just think: water and other elements are breaking down the rock. In this photo, you can see how water flowed continuously and over time it created a hole in this rock.

Carbonation • Carbonation takes place when carbon dioxide reacts with certain types of rocks forming a solution, that can easily be carried away by water.

Carbonation • White carbonate veins where carbon dioxide has been transformed into rock show in a dark deposit.

Let’s review all of that real quick… • What is chemical weathering? • Chemical reactions break down the bonds holding the rocks together, causing them to fall apart • Oxidation • Oxygen mixes with rock to make a new type of rock • Hydrolysis • Water breaks down rock • Carbonation • Carbon dioxide reacts and breaks down rock

Mechanical Weathering (This is also called Physical Weathering!) • Breaks rock into smaller pieces. • These smaller pieces are just like the bigger rock, just smaller. • That means,the rock has changed physically without changing its composition. • The smaller pieces have the same minerals, in just the same proportions as the original rock.

Hang on a sec… This is the MAIN difference between chemical and mechanical weathering! • In chemical weathering, the composition of the rock changes and a NEW type of rock is formed. • In mechanical weathering, the rock is broken down, but the type of rock is NEVER changed.

Ok, we can talk more about mechanical weathering now! • There are two types of mechanical weathering: • Ice wedging • Abrasion

Ice Wedging • Ice wedging is mechanical weathering where rocks are broken by water expanding as it is frozen. • When water flows into a crack and freezes itexpands and breaks the rock. In this picture, millions of years ago there was a glacier covering this rock. Water got into it, froze, expanded, and cracked the rock.

Ice Wedging or Frost Wedging(They mean the same thing )

Another example of frost wedging:

Abrasion • Rocks break into pieces by bumping into or rubbing againsteach other. • Gravity causes abrasion as a rock tumbles down a mountainside or cliff. • Moving water causes abrasion as particles in the water collide and bump against one another. • Strong winds carrying pieces of sand can sandblast surfaces. • Ice in glaciers carries many bits and pieces of rock. Rocks embedded at the bottom of the glacier scrape against the rocks below.

Abrasion: What does it look like? • Abrasion makes rocks with sharp or jagged edges smooth and round. • Like when you find pebbles at the beach! This one is abrasion from water causing the rocks to rub against and bump into each other. This one is abrasion from a glacier running over the rock and smoothing it out over time.

What now? • You need some practice! • Go to the VOISE Earth Science homework page and click on the weathering review activity.

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Weathering. This week we write it down if it’s in ORANGE. Photo: Grand Canyon, National Park Service. Wind blows sand and other sediment against rocks. Little by little, it wears away the rock! This is an example of mechanical weathering . What do you think made the hole in this rock?.

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Weathering. Ms. Carr 5 th Year Geography. Learning Outcome. Understand the main causes of Weathering. Identify the different types of weathering. Recognise a landform created as a result of one type of weathering. Weathering. Types of Weathering.

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Weathering. the process by which rocks on or near Earth’s surface break down and change. Two Types of Weathering. Mechanical (Physical) Weathering – only a physical change takes place. Chemical Weathering – a chemical change takes place. Mechanical Weathering.

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Weathering. Figure 6.1. Earth’s external processes. Weathering – the physical breakdown (disintegration) and chemical alteration (decomposition) of rock at Earth’s surface Mass wasting – the transfer of rock and soil downslope under the influence of gravity

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Weathering. Weathering and Erosion. Weathering is the chemical or physical breakdown of a rock or mineral due to exposure to the atmosphere . Erosion is the removal or transport of material by 5 possible agents: running water, glaciers, waves, wind, and gravity.

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WEATHERING. Weathering is the breaking down of earth rocks and matter. Weathering is. Breaking of rocks into smaller particles by mechanical and chemical processes.

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Weathering. By Lisa Bolin. Weathering and Erosion.

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Weathering. Types: Physical or mechanical (increases surface area) Chemical (chemical transformations) Congruent (complete dissolution) Incongruent (solids + dissolved products). Factors Controlling Chemical Weathering Rates. Mineralogy Surface area pH Temperature Organic acids

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Weathering. Erosion, Rivers and Glaciers. Weathering. The breakup of rock due to exposure to the atmosphere Can be Physical/Mechanical or Chemical. I. Physical/Mechanical Weathering. When rocks are split or broken into smaller pieces of the same material without changing the composition

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