Lesson 12: Weathering - Los Baños Senior High School PDF

LOS BAÑOS SENIOR HIGH SCHOOL Purok 2, San Antonio, Los Baños, Laguna LESSON 12: Weathering MOST ESSENTIAL LEARNING COMPETENCY (MELC) Describe how rocks undergo weathering LOS BAÑOS SENIOR HIGH SCHOOL...

LOS BAÑOS SENIOR HIGH SCHOOL Purok 2, San Antonio, Los Baños, Laguna LESSON 12: Weathering MOST ESSENTIAL LEARNING COMPETENCY (MELC) Describe how rocks undergo weathering LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering After this lesson, you are expected to: ✔ Identify the different agents of weathering ✔ identify the different types of physical and chemical weathering ✔ describe physical and chemical weathering ✔ explain how rocks undergo weathering LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering Earth’s surface is composed of water and landmasses. When rocks and minerals experience changes either physically or chemically, they are transported by different agents from one place to another and will settle down in a particular area. LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Weathering the process of disintegration and decomposition of rocks Physical Chemical LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Physical Weathering Also known as mechanical weathering Breakdown of rocks into pieces without any change in its composition The size and shape of rocks changes and this occurs because of these factors: Pressure Temperature LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Physical Weathering PRESSURE Due to tectonic forces, granite may rise to form mountain ranges. When pressure diminishes, the rock expands, cools, and become brittle and fractured. LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Physical Weathering TEMPERATURE Rocks expand and are fractured when exposed to high temperature. However, if the temperature drops to 0°C (freezing point of water), it also expands and causes fracture LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Physical Weathering Frost Abrasion Organic Activity Human Activity Burrowing Wedging Animals LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Physical Weathering FROST WEDGING Rocks have fracture in its surface and when water accumulates in the crack and at that point freezes, the ice expands and breaks the rock apart. LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Physical Weathering ABRASION Breakdown of rocks caused by impact or friction. Primarily occurs during collision of rocks, sand, and silt LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Physical Weathering ORGANIC ACTIVITY Roots grow causing penetration into the crack, expand, and in the long run, break the rock. Sometimes called “root action” LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Physical Weathering HUMAN ACTIVITIES Activities such as digging, quarrying, denuding forests and cultivating land contribute to physical weathering LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Physical Weathering BURROWING ANIMALS Animals like rats, rabbits, and squirrels excavate into the ground to create a space for habitation LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Chemical Weathering Dissolution Hydrolysis Oxidation LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Chemical Weathering DISSOLUTION Occurs in specific minerals which are dissolved in water The formation of stalactites and stalagmites in caves are brought about by this chemical reaction LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Chemical Weathering HYDROLYSIS Rock-forming minerals react with water and form different kinds of clay Some of these minerals include amphibole, pyroxene, and feldspar LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering  Chemical Weathering OXIDATION The response of oxygen with minerals If the iron oxidizes, the mineral in rocks decomposes Rusting is an example of this chemical reaction LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering LET’S RECAP! Weathering – breaking down and decomposition of rocks Two types of Weathering: 1. Physical weathering Frost wedging Abrasion Organic activity Human activity Burrowing animals 2. Chemical weathering Dissolution Hydrolysis Oxidation LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering QUIZ 1. What is Weathering? 2. Two Types of Weathering 3. Give at least two example LET’S REMEMBER! LOS BAÑOS SENIOR HIGH SCHOOL LESSON 12: Purok 2, San Antonio, Los Baños, Laguna Weathering