Geologic Processes and Hazards Lesson 2 PDF

GEOLOGIC PROCESSES AND HAZARDS GEOLOGY - Study of Earth and its history GEOLOGIC PROCESSES - Naturally occuring event that directly or indirectly impact the geology of the Earth. GEOLOGIC HAZARD - Extremely natural occuring event in the crust of the Earth that poses threat...

GEOLOGIC PROCESSES AND HAZARDS GEOLOGY - Study of Earth and its history GEOLOGIC PROCESSES - Naturally occuring event that directly or indirectly impact the geology of the Earth. GEOLOGIC HAZARD - Extremely natural occuring event in the crust of the Earth that poses threat to life and property. HAZARD - Refers to any source of potential harm, damage, or adverse effects on something or someone.  TYPES OF HAZARDS Biological Hazards Chemical Hazards Physical Hazards Technological Hazards Geologic Hazards - (ex. EARTHQUAKE)  EARTHQUAKE HAZARDS A. Ground Shaking - refers to the vibration of the ground during an earthquake. B. Surface Faulting - occurs when movement on a fault deep within the earth breaks through to the surface. EARTHQUAKE HAZARDS C. Liquefaction - Saturation of soil with water. Takes place when loosely packed, water- logged sediments at or near the ground surface lose their strength in response to strong ground shaking. EARTHQUAKE HAZARDS D. Fire (secondary effect of earthquake) - can cause electricity poles to fall and live wires to become exposed or to start fires. Ruptured gas lines and spillage of flammable substances. EARTHQUAKE HAZARDS E. Tsunamis - is a Japanese word that means "harbor wave." It's a series of giant waves caused by a sudden and powerful disturbance in a large body of water, usually an ocean. Causes of tsunami Underwater earthquakes Volcanic eruptions  VOLCANIC ERUPTION - happens when materials such as magma, ash, and gas are released from volcano due to a buildup of pressure inside. The effects of an eruption can be on a local scale affecting the areas near the volcano.  VOLCANIC HAZARDS A.Lahar - is an Indonesian term that describes a hot or cold mixture of water and rock fragments that flows down the slopes of a volcano and typically enters a river valley.  VOLCANIC HAZARDS B. Pyroclastic Flow - is a dense, fast-moving flow of solidified lava pieces, volcanic ash, and hot gases. It occurs as part of certain volcanic eruptions.  VOLCANIC HAZARDS C. Volcanic gases - are gases given off by active volcanoes. These include gases trapped in cavities in volcanic rocks, dissolved or dissociated gases in magma and lava, or gases emanating from lava, from volcanic craters or vents. Volcanic gases can also be emitted through groundwater heated by volcanic action.  VOLCANIC HAZARDS D.Tephra Fall - all pieces of all fragments of rock ejected into the air by an erupting volcano. Most tephra falls back onto the slopes of the volcano, enlarging it. LANDSLIDE - A landslide is the mass movement of rock, debris, or earth because of gravity. It encompasses falls, topples, slides, spreads, and flows. Human Activities that Trigger Landslides Construction activities Mining and quarrying operations Mudflow - mudflow, also known as mudslide or mud flow, is a form of mass wasting involving fast-moving flow of debris and dirt that has become liquified by the addition of water. Earthflow - is the downward flow of fine- grained materials, such as clay, fine sand, and silt. It is slower than mudflow, but it inflicts the same damage. Rockflow - is the sliding, toppling, or falling of rocks along a slope. It disrupts road traffic in mountainous regions. When it hits a structure or vehicle, it causes damage depending on the size of the rock and the force of impact. Geologic Hazard Map - geologic hazard maps gives the location of areas that are susceptible to dangerous event. - tool used by authorities to anticipate any hazard that a geological hazard event may bring.  Combined risk to geological disaster map  Earthquake hazard map  Tsunami hazard map  Map of distribution of volcano Overall Effects of Geologic Processes and Hazards Loss of life and injuries Destruction of Environmental Damage infrastructure Economic losses Disruption of services Psychological impact