SHS Earth Science Quarter 2 - Weathering Module

Changes in Rocks

• One of the changes rocks can undergo over time is weathering, a process that breaks down rocks into smaller fragments or sediments.

Importance of Taking Time

• It's essential to take your time when encountering difficulties in learning materials to ensure understanding andAvoidance of misconceptions.

Origin of Endogenous Processes

• Endogenous geological processes originate from within the Earth.

Seeking Assistance

• If you encounter difficulties, you can ask teachers or instructors for assistance with lessons and activities.

Learning Objectives

• After completing this learning material, students are expected to understand and describe the processes of rock weathering.

K-W-L Assessment

• The K-W-L (Know, Want to know, Learned) assessment evaluates students' prior knowledge and understanding of geological processes.

Weathering of Rocks

• Weathering is the breakdown of rocks into smaller fragments or sediments through physical or chemical processes.

Factors Affecting Weathering Rates

• Rocks on the Earth's surface weather faster than those underground due to exposure to environmental factors.

Physical Weathering

• Physical or mechanical weathering occurs through the fragmentation of rocks into smaller pieces without a change in composition.

Causes of Physical Weathering

• Unloading (release of pressure) and freeze-thaw cycles can lead to physical weathering.

Frost Wedging

• Frost wedging occurs when water seeps into cracks in rocks and expands as it freezes, causing the rock to break apart.

Thermal Expansion

• Thermal expansion, caused by temperature fluctuations, contributes to physical weathering by exerting pressure on rocks.

Effects of Temperature on Rocks

• When the temperature drops to 0°C, water in rocks expands, causing them to break apart.

Consequences of Weathering

• Weathering leads to the formation of sediments and the alteration of rocks.

Analogies to Physical Weathering

• Physical weathering is similar to the mechanical breakdown of materials, such as the crushing of rocks into gravel.

Factors Causing Weathering

• Factors that can cause weathering include temperature fluctuations, wind, water, ice, and pressure changes.

Learn about the process of weathering and its effects on rocks over short and long periods of time. Understand how endogenous geological processes originate from within the Earth itself.