Exogenic Processes PDF

FINALS LESSON NO. 1 EXOGENIC PROCESSES PREPARED BY:  EXOGENIC PROCESS - These are processes that take place at or near the earth’s surface that make the surface wear away. - Includes aggradation and degradation.  DIFFERENT TYPE OF EXOGENIC PROCESS...

FINALS LESSON NO. 1 EXOGENIC PROCESSES PREPARED BY:  EXOGENIC PROCESS - These are processes that take place at or near the earth’s surface that make the surface wear away. - Includes aggradation and degradation.  DIFFERENT TYPE OF EXOGENIC PROCESS 1.WEATHERING 2.EROSION 3.MASS WASTING  WEATHERING The physical breakdown and/or chemical alteration of rocks at or near the Earth’s surface is referred to as weathering. MECHANICAL WEATHERING Mechanical weathering or disintegration is the breaking up of large rocks into smaller fragments without changing the rock’s mineral composition.  MECHANICAL WEATHERING FROST WEDGING - Occurs in regions where temperature fluctuates above and below freezing point. - Repeated freeze-thaw cycle weakens the rock.  MECHANICAL WEATHERING THERMAL STRESS - Results from the expansion and contraction of rocks caused by temperature changes. - The outer surface of the rock is often warmer or colder than the inner portions. - The process of peeling off is called exfoliation.  MECHANICAL WEATHERING PRESSURE RELEASE - Occurs when the overlying rock is eroded away, causing the outer rock layer to expand more then the layer underneath. - The exfoliation due to the release is often called sheeting.  CHEMICAL WEATHERING Decomposition of rocks due to chemical reactions occurring between the minerals in rocks and the environment. CHEMICAL WEATHERING OXIDATION - Lose of Electron is Oxidation (LEO). - Iron-rich minerals are prone to oxidation. - Reddish-brown rust will appear on the surface which easily crumbs and weakens the rocks. CHEMICAL WEATHERING HYDROLYSIS - Hydro – water - Lysis – to dissolve - The new mineral appears to be chalky. CHEMICAL WEATHERING CARBONATION - Carbon dioxide dissolved in rainwater creates carbonic acid. - Carbonic acid reacts with Calcium carbonate it forms Calcium bicarbonate.  BIOLOGICAL WEATHERING PLANTS ANIMALS - Animals like earthworms, termites, ants and etc. breakdown the rocks through burrowing. HUMANS - Humans play a very important role in the weathering of rocks through different activities.  DIFFERENT TYPE OF EXOGENIC PROCESS 1.WEATHERING 2.EROSION 3.MASS WASTING  EROSION It transforms materials (sediments) from place to place through its agents. Forces: water, wind, and ice  TRANSPORT BY WATER - Water is the primary agent of Erosion. SPLASH EROSION SHEET EROSION  TRANSPORT BY WATER - Water is the primary agent of Erosion. GULLY EROSION BANK EROSION  TRANSPORT BY WIND - This is common in areas such as dessert. - Causes sand dunes and rock formation. SAND DUNES BANK EROSION  FACTORS IMPACTING EROSION  CLIMATE  VEGETATION  TOPOGRAPHY or TECTONIC ACTIVITY  DIFFERENT TYPE OF EXOGENIC PROCESS 1.WEATHERING 2.EROSION 3.MASS WASTING  MASS WASTING Bulk movements of soil, sand, and rock debris downslopes in response to the force of gravity or the rapid or gradual sinking of the Earth’s ground surface in a vertical direction. Driving force: gravity  TYPES OF MASS WASTING ROCK AND DEBRIS FALL - Rock fall occur when a piece of rock or mass of rock becomes dislodged and makes free-fall along steep cliff.  TYPES OF MASS WASTING LANDSLIDE - Sudden fast movement of a cohesive mass of soil, rock, or regolith. - Cause by failure: weathering, removal of vegetation, saturation of water to the slope  TYPES OF MASS WASTING FLOWS - Materials behave as liquid. - Commonly occur in humid areas.  ANGLE OF REPOSE Steepest-angle of dip relative to the horizontal plane to which a material can be piled up without slumping. fg = force of gravity fn = normal force fs = sheer force  ACTIVITY NO. 1 DIRECTION: Create a concept map about Exogenic Process. EXOGENIC ROCESS WEATHERING ___ EROSION ___ MASS WASTING ___ ___ ___ ___ ___ ___ ___  Rubrics Criteria Excellent (10 Proficient Satisfactory (6 Needs points) (8points) points) Improvement (5 point) Content Accuracy All key concepts Most key concepts Several important Many key (weathering, and sub-processes concepts are concepts are erosion, mass are included and missing or missing or wasting) and sub- accurately inaccurately inaccurately processes (types, explained, with represented. Basic explained. Major causes, examples) minor errors. explanations misunderstanding are accurately provided but s present. represented with lacking depth. correct definitions and explanations. Criteria Excellent (10 Proficient (8 Satisfactory (6 Needs points) points) points) Improvement (5 point) Organization Concept map is Concept map is Organization is Little to no well-organized, organized with somewhat organization. showing clear, clear unclear, and Relationships logical relationships, but relationships between concepts connections some connections between are unclear or between main may be unclear or processes are nonexistent. processes and incomplete. difficult to follow. their sub- Connections are processes. Lines weak. and arrows are used effectively to show relationships. Creativity & Effort The concept map Shows good Minimal creativity Little to no shows exceptional creativity and and effort shown. creativity or effort creativity and effort. Some extra Map meets basic shown. Map is effort. Extra features or requirements but incomplete or fails features like thoughtful lacks extra to meet basic illustrations or organization are thought or effort. requirements. advanced included. Meets structuring are basic