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• Geological Hazard


  Process or Phenomenon. Originates from the solid earth-geosphere.
• Landslide


  A downward movement of geological materials such as soil and rock. Landslides can be triggered by saturation of slope by extreme rainfall, or by vibration caused by earthquakes or by human activity.
• Types of Landslides


  • Creep
  • Slumps
  • Rockfall and topples
  • Mudslides
  • Debris slides and flow
• Creep


  • Generally slow, involve soil, and travel short distances
• Slumps


  • Can involve both soil and rock, travel short distances and vary from slow to very rapid
• Rockfall and topples


  • Involve rocks, are very to extremely rapid and can travel great distances
• Mudslides


  • Generally involve saturated soils moving at very to extremely rapid velocities and travel great distances
• Impending Signs of Landslide

  • New cracks or unusual bulges in the ground, street or sidewalks
  • Soil moving away from foundations, or the tilting or cracking of concrete floors and foundations
  • Sunken or down-dropped road beds
  • Rapid increase in creek water levels, possibly accompanied by increased soil content
  • A sudden decrease in creek water levels even though rain is still falling or just recently stopped
  • Unusual sounds, such as trees cracking or boulders knocking together, might indicate moving debris
• Effects of Landslide


  • Property damage, injury, and death and adversely affect a variety of resources such as water supplies, fisheries, sewage disposal systems, forests, dams, and roadways
  • Loss of property value, disruption of transportation routes, medical costs in the event of injury
  • Water availability, quantity, and quality can be affected
  • Geotechnical studies and engineering projects to assess and stabilize potentially dangerous sites can be costly
• Sinkhole


  Depressions or openings in the ground surface that naturally occur in areas underlain by soluble carbonate or evaporite rocks like limestone, dolomite, gypsum, and salt

  
• Types of Sinkholes


  • Dissolution sinkholes
  • Cover-subsidence sinkholes
  • Cover-collapse sinkholes

  
• Dissolution sinkholes


  • Aggressive dissolution occurs where flow is focused in pre-existing openings in the rock

  
• Cover-subsidence sinkholes


  • Tend to develop gradually where the covering sediments are permeable and contain sand
• Cover-collapse sinkholes


  • Tend to develop abruptly and cause catastrophic damages. They occur where the covering sediments contain significant amounts of clay.
• Karst terrain


  A type of topography that is formed by dissolution of bedrock in areas underlain by limestone, dolostone or gypsum, and has underground drainage systems reflected on the surface as sinkholes, springs, disappearing streams or even caves
• Impending Signs of Sinkholes

  • Trees or fence posts that tilt or fall

  
• Effects of Sinkholes


  • Both natural and human-caused sinkholes can pose great risk to local communities, resulting in partial or complete collapse of overground structures, damage to infrastructure, high economic losses, evacuation and displacement of residents, and in rare cases loss of lives. In nature, the impact is more limited to changes in regional topography, local fauna and flora, and sub-surface water ways.

  
• Hydrometeorological Hazard


  Process or phenomenon of atmospheric, hydrological or oceanographic nature. Natural process, but involved with the atmosphere and/or hydrosphere.
• Rainfall is the most important climatic element in the Philippines. Rainfall distribution varies from one region to another, depending upon the direction of the moisture-bearing winds and the location of the mountain systems.
• On average, 20 storms and typhoons hit the Philippines each year and they are growing progressively more destructive.
• The Philippines straddles the typhoon belt, an area in the western Pacific Ocean where nearly one-third of the world's tropical cyclones form. This area is not only the most active in the world, but also has the most intense storms globally.
• Typhoon


  A large, powerful and violent tropical cyclone
• Signs of Hydrometeorological Hazard


  • Increased ocean swell
  • Barometric pressure drop
  • Wind speed
  • Heavy rainfall
• Thunderstorm


  A weather condition that produces lightning, thunder and rain falls

  
• Signs of Thunderstorm


  • Cloud formation darkening sky
  • Lightning
  • Wind

  
• Flashflood


  A sudden destructive rush of water down a narrow gulley or sloping surface due to rainfall
• Signs of Flashflood


  • Continuous storms, typhoons and rain
  • Distant thunder
  • Rapidly rising water
  • Muddy water
  • Water carrying twigs, logs and other debris
• Flood


  An overflowing of a large amount of water beyond its normal confines, especially over what is normally dry land
• Storm Surge


  The rise of sea water above normal levels along the coast due to the strong winds and atmospheric conditions
• El Niño


  Unusually warm ocean temperatures in the equatorial Pacific
• La Niña


  Unusually cold ocean temperature in the equatorial Pacific which causes increased numbers of tropical storms
• Fire is the product from a chemical reaction between oxygen in the atmosphere and some sort of fuel. Oxygen, fuel and heat are needed for fire to occur.
• Classes of Fires


  • Class A - ordinary combustibles
  • Class B - flammable or combustible liquids and gases
  • Class C - energized electrical fires
  • Class D - combustible metals
  • Class K - cooking oils and grease
• Types of Burns


  • First degree - skin is red
  • Second degree - skin blisters
  • Third degree - skin is charred
• Lava Flow


  Stream-like flows of incandescent molten rock erupted from a crater or fissure
• Effects of Lava Flows

  • Lava flows can burn, melt and bury everything in their path
• Ashfall or Tephra Fall


  Showers of airborne fine- to coarse-grained volcanic particles
• Pyroclastic Flows and Surges

  Turbulent mass of ejected fragmented volcanic materials (ash and rocks), mixed with hot gases (200°C to 700°C to as hot as 900°C)
• Effects of Pyroclastic Flows and Surges

  • Can destroy anything on its path by direct impact, burn sites with hot rocks debris, and burn forests, farmlands, destroy crops and buildings
• Lahar


  Rapidly flowing thick mixture of volcanic sediments (from the pyroclastic materials) and water, usually triggered by intense rainfall during typhoons, monsoons and thunderstorms