ELS-Q1-M13-Geologic Processes & Hazards.pptx

Geologic Processes and Hazards
Geologic processes are natural events that shape the Earth's surface over time, both gradually and suddenly. Some of these processes can pose significant hazards to human life, infrastructure, and ecosystems. Understanding these processes helps predict potential hazards and mitigate their impacts.

Types of Geologic Processes
1. Internal Geologic Processes
These processes are driven by forces within the Earth, primarily due to heat and pressure from the planet’s interior.

Examples: Volcanism, tectonic activity, earthquakes, and mountain building.
Tectonic Activity

Plate Tectonics: Earth's crust is divided into tectonic plates that move due to mantle convection.
Effects:
Mountain formation: E.g., Himalayas (caused by collision of Indian and Eurasian plates).
Earthquakes: Caused by plate movements at faults (transform, convergent, and divergent boundaries).
Volcanism

Formation and eruption of volcanoes due to magma rising from the mantle.
Effects: Lava flows, ash clouds, pyroclastic flows, and gas emissions.
Earthquakes

Caused by the sudden release of stress along faults in the Earth's crust.
Effects: Ground shaking, surface rupture, and sometimes tsunamis.
Mountain Building (Orogeny)

When tectonic plates collide, they can push land upwards, forming mountain ranges.
2. External Geologic Processes
These processes occur at or near the Earth’s surface and are driven by external factors like gravity, water, wind, and ice.

Examples: Weathering, erosion, deposition, and mass wasting.
Weathering

The breaking down of rocks into smaller particles due to physical, chemical, or biological factors.
Physical Weathering: Frost wedging, thermal expansion.
Chemical Weathering: Oxidation, carbonation.
Biological Weathering: Tree roots breaking rocks apart.
Erosion

The transport of weathered materials by natural forces like water, wind, glaciers, and gravity.
Examples: River erosion (cutting valleys), wind erosion (forming dunes), glacial erosion (carving U-shaped valleys).
Deposition

The settling of eroded materials in a new location, forming landforms like deltas, alluvial fans, and sand dunes.
Mass Wasting (Landslides)

The movement of soil, rock, and debris down a slope due to gravity. Types include rockfalls, avalanches, and mudslides.
Geologic Hazards
1. Earthquakes
Hazard: Sudden ground shaking caused by fault movement.
Effects:
Building collapse, infrastructure damage, landslides, tsunamis.
Mitigation: Earthquake-resistant structures, early warning systems, and proper land use planning.
2. Volcanic Eruptions
Hazard: Explosions of magma, ash, and gases from volcanoes.
Effects:
Lava flows, ash fall, pyroclastic flows, volcanic gases, and lahar (mudflows).
Mitigation: Volcano monitoring, evacuation plans, and hazard maps.
3. Tsunamis
Hazard: Large ocean waves caused by undersea earthquakes, landslides, or volcanic eruptions.
Effects:
Coastal flooding, destruction of property, loss of life.
Mitigation: Early warning system

1. Geologic Processes & Hazards 1. Describe the various hazards that may happen in the event of earthquakes, volcanic eruptions, and landslides.

2. Group Work Activity Direction: Observe the following pictures, and write your observation on the Manila Paper and Present to the class your observation Guide Questions: 1. What factors determine the severity and impact of a geological hazard? 2. What are the potential impacts of geological hazards on human populations and infrastructure ?. 3. How can we identify areas that are at high risk of geological hazards?

3. Group Work Activity

4. Group Work Activity

5. are naturally occurring events that directly or indirectly impact the geology of the Earth. Examples of geological processes include events such as plate tectonics, weathering, earthquakes, volcanic eruptions, mountain formation, deposition, erosion, droughts . Geologic Processes

6. affect every human on the Earth all of the time, but are most noticeable when they cause loss of life or property. These threatening processes are called natural disasters. Geologic Processes

7. A refers to a catastrophic event caused by the dynamic processes of the Earth. These disasters are typically sudden and can result in significant damage to the environment, infrastructure, and human life. Geologic Hazard

8. It is a large-scale, complex natural events that happen on land. These hazards can cause immense damage, loss of property, and sometimes life. Geologic Hazard

9. Geologic Hazards are Earthquakes Volcanic eruptions, Tsunamis (tidal waves ), Landslides Geologic Hazard

10. Earthquakes Caused by the sudden release of energy along faults. They can lead to ground shaking, surface rupture, and secondary effects like landslides and tsunamis. Geologic Hazard

11. Tectonic Earthquakes Caused by Tectonic Plate Movements Convergent Boundaries Divergent Boundaries Transform Boundaries Types and Causes of Earthquakes

12. 2 . Volcanic Earthquakes Caused by Volcanic Activity Earthquakes can occur before, during, or after volcanic eruptions due to the movement of magma and volcanic gases. Types and Causes of Earthquakes

13. 3. Induced Earthquakes Caused by human a ctivities Activities such as mining, reservoir-induced seismicity (due to the filling of large reservoirs behind dams), and hydraulic fracturing (fracking) can induce seismic activity. Types and Causes of Earthquakes

14. Seismology is the scientific study of earthquakes and the propagation of seismic waves through the Earth . Seismographs an instruments that measure and record seismic waves. Seismic waves are waves of energy that travel through the Earth's interior and along its surface as a result of seismic events, such as earthquakes, volcanic eruptions, or explosions. Measurement and Magnitude

15. Richter Scale Measures measures magnitude of an earthquake based on the amplitude of seismic waves . 2. Mercalli Intensity Scale m easures the intensity of shaking and damage caused by an earthquake, ranging from I (not felt) to XII (total destruction). Measurement and Magnitude

16. Ground Shaking Can cause buildings to collapse, landslides, and ground rupture . 2. Surface Rupture The displacement of the Earth's surface along the fault line can damage infrastructure and alter landscapes. Effects of Earthquakes

17. 3. Secondary Effects Tsunamis : Undersea earthquakes can trigger tsunamis, leading to coastal flooding and damage . Landslides : Earthquake shaking can trigger landslides, especially in hilly or mountainous areas Fires : Broken gas lines and electrical faults can ignite fires. Effects of Earthquakes

18. 4. Economic and Social Impact. Destruction of homes, businesses, and infrastructure can lead to significant economic losses and displacement of communities. Effects of Earthquakes

19. 4 . Liquefaction describes the way in which soil liquefies during ground shaking. Liquefaction can undermine the foundations and supports of buildings, bridges, pipelines, and roads, causing them to sink into the ground, collapse, or dissolve. Effects of Earthquakes

20. 1. The 1968 Casiguran Earthquake Magnitude: Approximately 7.3 2. The 1990 Luzon Earthquake Magnitude : 7.7 3. The 2013 Bohol Earthquake Magnitude : 7.2 4. The 2019 Mindanao Magnitudes : 6.3 (October 16) and 6.6 (October 29 ) 5. The 2022 Abra Earthquake Magnitude : 7.0 Most notable earthquakes in the Philippines

21. Volcanic eruptions are geological events that occur when magma from beneath the Earth's surface reaches the surface through volcanic vents. Geologic Hazard

22. Effusive Eruptions Characterized by the relatively gentle flow of magma onto the surface . 2. Explosive Eruptions Involves violent explosions that eject magma, ash, and gases into the atmosphere. Types of Volcanic Eruption

23. 3. Phreatomagmatic Eruptions Occur when magma interacts with water, leading to explosive steam-driven eruptions . 4. Strombolian Eruptions Characterized by intermittent, explosive bursts of gas and magma. Types of Volcanic Eruption

24. 5 . Vulcanian Eruptions Involves short, violent explosions of gas and ash from a volcanic vent . Types of Volcanic Eruption

25. Lava Flows Impact : Can destroy buildings, roads, and vegetation, but typically move slowly enough to allow for evacuation . 2. Ashfall Impact : Can cause respiratory problems, damage crops, contaminate water supplies, and disrupt transportation. Volcanic Hazards

26. 3. Pyroclastic Flows Impact : High-temperature, fast-moving flows of gas and volcanic material that can devastate everything in their path. 4. Lahars Volcanic mudflows that occur when volcanic ash and debris mix with water, often from heavy rains or melting snow . Volcanic Hazards

27. Mount Pinatubo (1991) Zambales , Tarlac , and Pampanga provinces, Luzon The eruption of Mount Pinatubo is considered one of the largest volcanic eruptions of the 20th century. Approximately 800 people died ,. Over 200,000 homes were damaged or destroyed. Most famous volcanic eruptions in the Philippines

28. 2. Mount Mayon (Multiple Eruptions ) Albay province, Luzon Is one of the Philippines' most active and iconic volcanoes, known for its nearly perfect cone shape . The 1814 eruption was one of the most devastating, burying the town of Cagsawa and killing over 1,200 people. Most famous volcanic eruptions in the Philippines

29. 3 . Taal Volcano (2020 ) Batangas province, Luzon is one of the world's smallest active volcanoes but also one of the most dangerous . The eruption forced the evacuation of more than 300,000 people from surrounding areas. Most famous volcanic eruptions in the Philippines

30. 4 . Mount Hibok-Hibok (1951) Camiguin Island, Northern Mindanao Mount Hibok-Hibok is one of the several volcanoes on Camiguin Island . The eruption killed more than 500 people and caused widespread destruction. Most famous volcanic eruptions in the Philippines

31. 5. Mount Kanlaon (1996) Negros Island, Central Visayas Mount Kanlaon is an active stratovolcano and the highest point on Negros Island. The eruption caused the death of three hikers who were caught near the summit during the explosion. Most famous volcanic eruptions in the Philippines

32. 6. Mount Bulusan Sorsogon province,Luzon is one of the most active volcanoes in the Philippines, with several recorded eruptions throughout history . These eruptions have caused ashfall in nearby towns and led to evacuations and disruptions to local communities. Most famous volcanic eruptions in the Philippines

33. 7. Mount Ragang ( 1865) Lanao del Sur, Mindanao Also known as Mount Piapayungan , is one of the active volcanoes in Mindanao. While detailed historical records are limited, the eruption was significant enough to be noted in historical accounts. Most famous volcanic eruptions in the Philippines

34. 3. Tsunamis ( tidal waves ) is a series of large ocean waves typically caused by underwater seismic activity, such as earthquakes, volcanic eruptions, or underwater landslides Geologic Hazard

35. 3. Tsunamis (tidal waves) These disturbances displace a large volume of water, creating waves that can travel across entire ocean basins at high speeds . Geologic Hazard

36. 4. Landslide is a natural disaster involving the movement of rock, earth, or debris down a slope. It can occur due to a variety of factors, including gravitational pull, water saturation, erosion, volcanic activity, earthquakes, or human activities Geologic Hazard

37. Natural Factors: Steep slopes, heavy rainfall, earthquakes, volcanic activity, and weathering . Human Activities: Deforestation, mining, construction, and improper land use. Factors Contributing to Landslides

38. The 1991 Ormoc Tragedy Incident : Incident: On November 5, 1991, Typhoon Uring brought torrential rains to the region . The disaster claimed the lives of around 5,000 people, with some estimates going higher. Some notable victims and incidents involving landslides in the Philippines

39. 2 . Guinsaugon , Southern Leyte (2006 ) Incident : On February 17, 2006, a massive landslide buried the entire village of Guinsaugon in Southern Leyte, following ten days of heavy rains and a minor earthquake. Some notable victims and incidents involving landslides in the Philippines

40. 3. Cherry Hills Subdivision, Antipolo (1999 ) Incident : A landslide occurred on August 3, 1999, after continuous heavy rains, causing a portion of the Cherry Hills Subdivision in Antipolo City to collapse. Some notable victims and incidents involving landslides in the Philippines

41. 4. Barangay Lipata , Tacloban City, Leyte (2018 ) Incident : On January 13, 2018, heavy rains triggered a landslide in Barangay Lipata in Tacloban City, Leyte. Some notable victims and incidents involving landslides in the Philippines

42. My Geologic Hazards Experience Write at least four (4) hazards you have experienced in your locality. Then make a slogan on how these hazards affect the people as well as the environment. Activity