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  • 1. “NOTHING IS PERMANENT ON THE EARTH’S SURFACE. THE CRUMBLING FOUNDATION OF AN OLD BUILDING, THE WORN-OUT INSCRIPTION ON A MARBLEGRAVESTONE, THE BROKEN ROCK ALONG THE ROAD, ANDTHE CONCAVE SURFACES OF THE ROCKS ON WHICH THERAIN FALLS – ALL THESE TELLS US THAT EVEN ROCKS ARE SUBJECT TO DESTRUCTION.” Reported by: Ebenezer Gildo
  • 2. WEATHERING – THE GENERAL TERM DESCRIBING ALL THE CHANGES THAT THE RESULT FROM THE EXPOSURE OF ROCK MATERIALS TO THE ATMOSPHERE. THIS INCLUDE CHEMICAL, PHYSICAL, AND BIOLOGICAL PROCESSES.TWO TYPES OF WEATHERING: - MECANICAL WEATHERING - CHEMICAL WEATHERING Reported by: Ebenezer Gildo
  • 3. MECHANICAL WEATHERING CHEMICAL WEATHERING TAKES PLACE WHEN ROCKS ARE CRACKED, SPLIT, INVOLVES THE COMPLEX PROCESS THAT ALTERS THEOR BROKEN INTO SMALLER PIECES WITHOUT CHANGING INTERNAL STRUCTURES OF MINERALS BYTHEIR COMPOSITION. REMOVING AND ADDING ELEMENTS.• ICE OR FROST WEDGING - FREEZING WATER EXPANDS IN • CARBONATIONCRACKS OR BEDDING PLANES AND WEDGES THE ROCK. • OXIDATION• SHEETING OR UNLOADING - A SERIES OF FRACTURES IS • HYDRATIONPRODUCED BY EXPANSION OF THE ROCK BODY ITSELF.•THERMAL EXPASION – HEAT MAKES A ROCK EXPAND.• EXFOLIATION - SPALLING OF LAYERS OF ROCKS• BIOLOGICAL ACTIVITIES• MAN’S ACTIVITIES Reported by: Ebenezer Gildo
  • 4. THE MOST IMPORTANT PRODUCT OF WEATHERING IS SOIL. SOIL IS USUALLY UNDERSTOOD TO BE MORE THAN JUST LOOSE WEATHERED MATERIALS SUCH AS SAND OR CLAY. SOIL IS A MIXTURE OF UNCONSOLIDATED WEATHERED EARTH MATERIALS AND DECAY-RESISTANT ORGANIC MATTER CALLED HUMUS.THERE ARE THOUSANDA OF DIFFERENT SOIL TYPES, DEPENDING ON THE PARENT ROCK TYPE, CLIMATE,TIME ACCUMULATION, TOPOGRAPHIC RELIEFE, ELEVETION, RAINFALL, PERCENTAGE OF CLAY, SAND, OR SILT, AMOUNT OF HUMUS, AND A NUMBER OF OTHER ENVIRONMENTAL VARIALBES. SOILS THAT IS FORMED IN COLD & DRY CLIMATES ARE SHALLOWER WITH LESS HUMUS THAN SOILS FORMED IN WET & WARM CLIMATES. Reported by: Ebenezer Gildo
  • 5. • The most important product of weathering soil• Is a mixture of unconsolidated weathered earth materials and decay-resistant organic matter called humus• Soils formed in cold and dry climates are shallower with less humus than soils formed in wet and warm climates. Reported by: Patricia Kim Llagas
  • 6. • A soil that has a balanced amounts of sand, silt, and clay mixed with abundance of humus• It is a great soil for gardening since it is fertile and well-drained, yet holds enough moisture for sustained plant growth• It is found in the top layer of the soil , so it is also referred to as topsoil Reported by: Patricia Kim Llagas
  • 7. It is a layer of soil with differentphysical and chemical properties Reported by: Patricia Kim Llagas
  • 8. • A-Horizon- is the zone containing the most humus• B-Horizon- often clayish and stained red or brown by iron oxides leached from A- horizon• C-Horizon- consists of incompletely weathered parent material. Reported by: Patricia Kim Llagas
  • 9. Climate is one of theenvironmental factors that affect soil character Reported by: Patricia Kim Llagas
  • 10. • Soils formed in wet, humid climate are characterized by strong leaching and percolation and tend to be more acid from the decay of abundant humus is called pedalfers• Soil that form in dry climates tend to have little leaching and scant humus since less vegetation is produced is called pedocals• Areas with tropical climates of a year- round warm temperature and high amounts have highly leached soils called laterites Reported by: Patricia Kim Llagas
  • 11. • Is the process by which weathered materials are moved or carried away by natural agents Reported by: Patricia Kim Llagas
  • 12. • Is the movement of earth caused by gravity• In general the mass movement can be classified into 3 criteria: – (1) the type of material moved, – (2) the rate of the movement and – (3) the type of movement Reported by: Patricia Kim Llagas
  • 13. • Fall- describes materials in vertical or near vertical freefall bounding down a cliff• Slip- describes materials that are moving together along one or more well-define surfaces• Flow-describes a mass that is moving as more or less viscous fluid Reported by: Patricia Kim Llagas
  • 14. Reported by: Patricia Kim Llagas
  • 15. Reported by: Patricia Kim Llagas
  • 16. Reported by: Patricia Kim Llagas
  • 17. Reported by: Patricia Kim Llagas
  • 18. Reported by: Patricia Kim Llagas
  • 19. • Debris Avalanche- is a mass movement of a wide variety of materials such as rocks, trees, and soils, in a single chaotic flow Reported by: Patricia Kim Llagas
  • 20. Reported by: Arjay Alexis Otic
  • 21. Reported by: Arjay Alexis Otic
  • 22. • Meanders - a turn or winding of a stream Reported by: Arjay Alexis Otic
  • 23. Process on a meander bend Reported by: Arjay Alexis Otic
  • 24. Reported by: Arjay Alexis Otic
  • 25. Reported by: Arjay Alexis Otic
  • 26. Reported by: Arjay Alexis Otic
  • 27. • What is a floodplain?• floodplain - a low plain adjacent to a river that is formed chiefly of river sediment and is subject to flooding Reported by: Arjay Alexis Otic
  • 28. Reported by: Arjay Alexis Otic
  • 29. Definition of delta• Delta - A usually triangular mass of sediment, especially silt and sand, deposited at the mouth of a river. Deltas form when a river flows into a body of standing water, such as a sea or lake, and deposits large quantities of sediment. They are usually crossed by numerous streams and channels and have exposed as well as submerged areas. Reported by: Arjay Alexis Otic
  • 30. Reported by: Arjay Alexis Otic
  • 31. • Glaciers - A large mass of ice moving very slowly that moves under its own weight through a valley or spreading outward from a center.• It takes about 5 to 3500 years for snow to transform into glacial ice. Depending on the climate and temperature in the environment. Reported by: Arjay Alexis Otic
  • 32. Reported by: Arjay Alexis Otic
  • 33. • Alpine glaciers, even though they move, are confined to mountain valleys, which in most instances had previously been a stream valley. a• Continental ice sheets exist on a much larger scale. These huge masses flow out in all directions from one or more centers of the land. They cover the entire continent, hence the name, and extend out toward the sea. Only two exist today: Greenland and Antarctica. Reported by: Arjay Alexis Otic
  • 34. Picture of an alpine glacier Reported by: Arjay Alexis Otic
  • 35. Pictures of a continental glacier Reported by: Arjay Alexis Otic
  • 36. Reported by: Arjay Alexis Otic
  • 37. Glacial erosion and deposition• Glacial bulldozing – is the pushing along of rocks, soil, and sediments by the leading edge of an advancing glacier. Reported by: Arjay Alexis Otic
  • 38. Glacial erosion and deposition• Glacial plucking – occurs as water seeps into cracked rocks and freezes, becoming part of the solid glacial mass… Reported by: Arjay Alexis Otic
  • 39. Glacial erosion and deposition• Glacial abrasion – occurs as the rock fragments frozen into the moving glacial ice scratch, polish, and grind against surrounding rocks at the base and along the valley paths. Reported by: Arjay Alexis Otic
  • 40. Reported by: Arjay Alexis Otic
  • 41. Aeolian ProcessesActivity of the wind – its ability to shape theEarth’s surface, and its importance in arid environments such as deserts.*Aeolian – derived from the word Aeolus, the Greek god of wind Reporter: Jeflyn C. Rastrollo
  • 42. EROSIONTRANSPORTATION DEPOSITION Reporter: Jeflyn C. Rastrollo
  • 43. I. EROSION• result of material (sediments/soil particles) movement by the wind• not a strong force – not as damaging as with water and soil erosion• generally occurs in arid areas where there is little or no vegetation• Wind can erode by 2 processes: – Deflation (removal of loose, fine-grained particles) – Abrasion (wearing down of surfaces by the grinding action and sandblasting of windborne particles) Reporter: Jeflyn C. Rastrollo
  • 44. A. DEFLATION ~lowering of land surface due to removal or picking-up (by the wind) of loose, fine-grained materials (silt and sand)~• …most active where winds are unobstructed, and materials are exposed and not protected by vegetation (i.e. deserts, beaches, and on unplanted farmland)• Regions which experience intense and sustained erosion are called deflation zones, which are composed of desert pavement – a sheet-like surface of rock fragments that remains after the fine particles were removed C. Rastrollo Reporter: Jeflyn
  • 45. DESERT PAVEMENT Reporter: Jeflyn C. Rastrollo
  • 46. 2 THEORIES REGARDING THE FORMATION OF DESERT PAVEMENT1. Wind blows away sand and silt, leaving the pebbles that protects the layer below.2. Wet pavement swells, raising the pebbles – as it dries and shrinks, sand falls between the cracks, leaving the pebbles Reporter: Jeflyn C. Rastrollo
  • 47. B. ABRASION~ wearing down of surfaces by the grinding action and sandblasting of windborne particles ~ Wind-driven grains abrades landforms by grinding of the particles carried in the wind, which creates grooves or small depressions. Reporter: Jeflyn C. Rastrollo
  • 48. ovesgro Reporter: Jeflyn C. Rastrollo
  • 49. si on pr esde Reporter: Jeflyn C. Rastrollo
  • 50. Ventifacts are rocks sculptured and shaped (cut and polished)by the abrasive action of wind-blown sediments Reporter: Jeflyn C. Rastrollo
  • 51. II. TRANSPORTATION Particles (keeping the particle size intoconsideration) are transported by windsalong the surface through three variousmodes – creep, saltation, and short-termand long-term suspension – i.e. hours anddays. Reporter: Jeflyn C. Rastrollo
  • 52. A. SALTATION (skipping or bouncing)• Wind transports sediment near the surface by saltation.• Saltation is downwind movement of particles in a series of jumps or skips. Saltation normally lifts sand-size particles no more than one centimeter above the ground, and proceeds at one-half to one- third the speed of the wind. A saltating grain may hit other grains that jump up to continue the saltation. Reporter: Jeflyn C. Rastrollo
  • 53. Saltation moves small particles in the direction of the windin a series of short hops or skips. Reporter: Jeflyn C. Rastrollo
  • 54. B. SUSPENSION• Sand sized particles generally do not travel very far in the wind, but smaller sized fragments can be suspended in the wind for much larger distances.• Upward currents of air support the weight of suspended particles and hold them indefinitely in the surrounding air. Typical winds near Earths surface suspend particles less than 0.2 millimeters in diameter and scatter them aloft as dust or haze. Reporter: Jeflyn C. Rastrollo
  • 55. Reporter: Jeflyn C. Rastrollo
  • 56. C. CREEPING (rolling or sliding)• The saltating grain may also hit larger grains, called surface creeps that are too heavy to hop, but instead slowly creep or roll forward as they are pushed by saltating grains.• Surface creep accounts for as much as 25% of grain movement in a desert. Reporter: Jeflyn C. Rastrollo
  • 57. III. DEPOSITION• A wind process that deposits particles into bodies that occur as sand sheets, ripples, and dune.• Most common wind deposits are (1) dunes, and (2) loess. Reporter: Jeflyn C. Rastrollo
  • 58. A. SAND RIPPLES Occur as a result of larger grainsaccumulating as smaller grains aretransported away. Wind blowing on a sandsurface ripples the surface into crests andtroughs. In ripples, the coarsest materialscollect at the crests. This distinguishes smallripples from dunes, where the coarsestmaterials are generally in the troughs. Reporter: Jeflyn C. Rastrollo
  • 59. B. SAND SHEETS Sand sheets are flat, gentlyundulating sandy plots of sandsurfaced by grains that may be toolarge for saltation. Reporter: Jeflyn C. Rastrollo
  • 60. C. SAND DUNES• Forms when there is : 1. A ready supply of sand 2. A steady wind 3. Some kind of obstacle (vegetation, rocks or fences) to trap some of the sand• Forms when moving air slows down on the downwind side of an obstacle; the sand grains drop out and form a mound that becomes a dune.• Sand dunes are mounds with a gentle slope in the upwind direction and steep slope called a slip face on the downwind side. Dunes migrate by erosion of sand by wind (saltation) on the gentle upwind slope, and deposition and sliding on the slip face. Reporter: Jeflyn C. Rastrollo
  • 61. Sand dunes are mounds with a gentle slope in theupwind direction and steep slope called a slip face on thedownwind side. Dunes migrate by erosion of sand by wind(saltation) on the gentle upwind slope, and deposition andsliding on the slip face. Reporter: Jeflyn C. Rastrollo
  • 62. D. LOESS• Loess is a homogeneous, typically nonstratified, porous, friable, slightly coherent, often calcareous, fine-grained, silty, pale yellow or buff, windblown (Aeolian) sediment.• Loess often stands in either steep or vertical faces. Loess tends to develop into highly rich soils. Under appropriate climatic conditions, areas with loess are among the most agriculturally productive in the world. Loess deposits are geologically unstable by nature, and will erode very readily. Therefore, windbreaks (such as big trees and bushes) are often planted by farmers to reduce the wind erosion of loess. Reporter: Jeflyn C. Rastrollo
  • 63. Effects of Soil Erosion (losses caused by erosion) Reporter: Jeflyn C. Rastrollo
  • 64. Soil erosion does decrease productivity.When it happens very gradually, has minimaleffect on the land with enough time for new soilto form. But accelerated erosion is detrimental.Lets look at some of the ill-effects of soilerosion: • It decreases soil fertility. • It causes a decrease in crop production and crop quality. • It can be a safety hazard as the eroding land can lead to accidents and soil that shifts and gets deposited on roads and streets can make driving difficult. Reporter: Jeflyn C. Rastrollo
  • 65. Reporter: Jeflyn C. Rastrollo
  • 66. • It can cause environmental damage as loss of soil can make it difficult for natural vegetation to grow in it and thus turn a fertile land into a desert. Another issue is the sediment shifted by water currents and deposited in ponds, which can hurt marine animal and plant life. The soil can cover up fish eggs and prevent their hatching. Or the soil particles stay suspended in water, preventing light from reaching marine plants to allow the photosynthesis process and also retaining heat and raising the water temperature. The soil particles are also abrasive on fish and plant tissue and can kill them off.• It can lead to financial issues. You need expensive filtration methods to get drinkable water. Soil loss leads to crop failure and more financial loss. Reporter: Jeflyn C. Rastrollo
  • 67. Reporter: Jeflyn C. Rastrollo
  • 68. Economic EffectRemoval of nutrients, organic materials, and fine particles from the topsoil Lower crop yields & Increase in the cost of farming (fertilizer) Lower profits for farmers & Higher food prices for consumers Reporter: Jeflyn C. Rastrollo
  • 69. Effect on Water Eroded sediments passes into water sources(possibly containing pesticides and other harmful chemicals Increase in the amount of phosphorus and nitrogen in the water Decrease in water oxygen levels Poor water quality Reporter: Jeflyn C. Rastrollo
  • 70. Erosion Control (preventive measures)*The main cause of soil erosion is the removal of vegetation. Main solution:increase of vegetation Reporter: Jeflyn C. Rastrollo
  • 71. When the land is covered with vegetation, the roots of the plants and trees interlock and interlace to bind the soil particles. This helps in 2 ways:• does not allow the soil particles to be carried away by wind or water• the falling leaves of the plants get converted to humus by decomposing action of the soil microbes. This enriches the soil. Reporter: Jeflyn C. Rastrollo
  • 72. Several methods can be employed to increase the vegetation cover of land. Some of them are as follows:• Crop rotation (fallowing) – practice of growing diff. crops at diff. times on the same land; this keeps the topsoil covered with vegetation at the same time enriching the soil Reporter: Jeflyn C. Rastrollo
  • 73. Reporter: Jeflyn C. Rastrollo
  • 74. 2. Reforestation – growing trees on lands which have lost their vegetation, esp. on slopes because they are more subject to soil erosion by running water3. Strip cropping – involves growing of crops in strips; 2 common methods followed: • Contour farming – strips of crops are at right angles to the slope (practiced on sloping lands) • Wind-strip cropping – strips of crops are placed at right angles to the direction of the wind Reporter: Jeflyn C. Rastrollo
  • 75. Reporter: Jeflyn C. Rastrollo
  • 76. Reporter: Jeflyn C. Rastrollo
  • 77. 4. Restoring soil fertility – addition of natural (mulch) and synthetic fertilizers, because fertile soil supports vegetation Loss of soil fertility Loss of vegetation Exposure of land to erosion Reporter: Jeflyn C. Rastrollo
  • 78. 5. Control of Grazing – cattle grazing on small plants and grasses, which helps the topsoil to remain in place, should be allowed only on the land meant for the purpose and other areas should be protected from grazing.6. Dam building – With the dams the speed and amount of water flowing can be controlled. This will control the soil erosion of the river banks. Reporter: Jeflyn C. Rastrollo
  • 79. Reporter: Jeflyn C. Rastrollo
  • 80. 7. Wind Breakers (crop cover) – Trees are planted across the wind direction to protect against the high velocity winds. These rows of trees are called shelter belts or wind breakers.8. Total log ban – slashing of trees in forest is prevented, so that wild animals and forest creatures will not be deprived of their habitat Reporter: Jeflyn C. Rastrollo
  • 81. Reporter: Jeflyn C. Rastrollo
  • 82. 9. Mechanical Blockage – Use of physical barriers such as riprap (broken rocks) and gabion strips (wire baskets), specifically-designed to prevent water from eroding the soil on the land10. Conservation tillage – farming practiced with a minimum amount of tillage because tillage process displaces soil layers and makes it loose, making it more prone to get eroded Reporter: Jeflyn C. Rastrollo
  • 83. Reporter: Jeflyn C. Rastrollo