Natural Disaster Final
General Geology:
-How do natural disasters influence the population?
Natural disasters can displace populations, destroy infrastructures, lead to deaths, and cause long tetm economic challenges
-How can natural disasters be evaluated in terms of occurrence, risks and the environment?
They are evaluated using historical records, geographic risk mapping, environmental impact assessments, and modeling future occurrences using scientific tools.
-What are examples of natural disasters/hazards?
Earthquakes, tsunamis, hurricanes, floods, landslides, volcanic eruptions, droughts, and wildfires are examples
-What is the rock cycle?
The rock cycle describes the continuous transformation of rock types: igneous (from molten material), sedimentary (from compaction of sediments), and metamorphic (altered by heat and pressure).
Plate Tectonics:
-How does the structure of the earth help us to understand plate tectonics?
The earths layers- crust, mantle, outer core, inner core- interact through convection currents in the mantle, driving plate movement.
-How is the earth’s magnetic field formed? How to reversals in polarity help scientists to understand plate tectonics? How are reversals in polarity determined?
The magnetic field is generated by convection in the liquid core. Reversals, recorded in seafloor rocks, reveal plate movements and age of oceanic crust through magnetic “stripes”.
-Why is plate tectonics called the unifying theory?
It explains diverse geological phenomena, including earthquakes, volcanoes, mountain formation, and continental drift.
-What other geologic features are used to help build and describe the mechanisms for plate tectonics?
Mid-ocean ridges, subduction zones, rift valleys, and transform faults.
-What are the 3 types of plate margins? What happens along these margins? What geologic features are associated with each type of plate margin?
Divergent boundaries: plates move apart (mid ocean ridges)
convergent boundaries: plates collide (moutain ranges)
Transform: plates slide past each other (san andreas fault)
Earthquakes
-What causes earthquakes? What is stress? What is strain? How are stress and strain related in earthquakes?
Earthquakes occur from sudden energy release along faults. Stress is the force applied; strain is the deformation caused by stress.
-What is elastic rebound?
The sudden release of accumulated energy when rocks snap back to their original shape after strain.
-What are faults? How do they form? What are the different type of faults?
Cracked in earths crust where movement occurs. Types inclue normal, reverse, and strike-slip faults.
-What are seismic waves? What are the 4 types of seismic waves? How do the types of seismic waves differ? What are P- and S-waves used to determine? What is the significance of R-and Lwaves? How are seismic waves measured?
P-waves: fastest, compressional
S-waves: slower shear
R-waves and L-waves: surface waves, caused most damage
-What is the difference between magnitude and intensity?
Magnitude measures energy released; intensity measures effects on the surface
-What is the focus and epicenter of an earthquake? How are they determined?
Focus: point of energy release
Epicenter: surface location above the focus
-What are hazards that are caused during an earthquake?
Ground shaking, liquefaction, tsunamis, and landslides
-Where do earthquakes generally occur?
On fault lines
-Why do earthquakes occur in the center of continents?
Due to ancient faults and reactivation from stress redistribution
-How are earthquakes predicted?
Off of tiny movements in the cracks
-General information about specific earthquakes discussed in class, including documentaries.
We learned about the fault lines like the san andreas
-What is a tsunami? What causes a tsunami?
A large sea wave caused by underwater earthquakes or landslides
-How do tsunamis form? What is the difference between a tsunami and an ocean wave?
Because of earthquakes in the water. They cause tsunamis to form. Tsunamis are much larger than waves
-How does geography impact tsunamis?
Coastal topography, ocean floor features, proximity to the tsunami source, island chains and archipelagos, human development and urban planning, tsunami shadow zones, regional climate and seasonal conditions
Volcanoes:
Formation of melt and igneous rocks (types of igneous rocks)
-What controls viscosity?
Temperature, silica content, and gas content of magma
-How do intrusive and extrusive rocks differ?
Intrusive: from inside earth, coarse-grained (granite)
Extrusive: From at the surface, fine-grained(basalt)
-Where do basaltic, granitic, and andesitic magmas originate?
Basaltic: Partial melting of the upper mantle
Granitic: partial melting of the continental crust or the lower crust
Andesitic: partial melting and mixing of mantle derived basaltic magma with crustal material or from fractional crystallization of basaltic magma
-What is the physical and chemical difference between shield and composite volcanoes?
Shield: broad, gentle slopes, basaltic lave
Composite: steep, andesitic/rhyolitic lava, explosive eruptions
-How do magmas differentiate? How do magmas change composition?
They come from different sources
-How do melts form? Hint: The are two methods
Textures and minerals
Bowen's Reaction Series
-Volcanic eruption types? Volcanic hazards?
Lava flows, pyroclastic flows, ash fall, and lahars
-Intrusive vs extrusive igneous rocks
Composition (felsic, intermediate, mafic, ultramafic)
-What major hazards caused the fatalities in the eruptions discussed in lecture?
Cyroplasitc flows
-How are volcanoes monitored?
Using seismic activity, gas emissions, ground deformation, and satellite imagery
-What are different types of lava?
Basaltic, andesitic, rhyolitic
-Why do volcanoes erupt?
They can because of earthquakes or other things
-How are volcanic eruptions predicted? What precautions can people take to prepare for an eruption?
Because of the gas levels or little earthquakes happening
Mass Wasting
-Types of weathering and relationship to mass wasting?
Landslides
-What are the controls for mass wasting? What would you look for as an indication that mass wasting has happened or is likely to happen?
Slope angle, water content, vegetation, and type of material.
-What are the types of mass wasting events?
Falls, slides, flows, creeps
-What is mass wasting?
Movement of the ground
-What are the triggers for mass wasting?
Earthquakes or like humans
-What are precautions we can take to limit mass wasting events?
Stabiliing slopes, drainage control, and vegetation planting
Water Cycle:
-What is the water cycle? What is the distribution of water around the world?
Continuous movement of water through evaporation, condensation, precipitation, and runoff
-How do streams form?
They form by forcing themselves through
-What is flooding? Where and what causes flooding issues in a region?
When water goes where it isnt supposed to be
-What structures are associated with river and streams?
Dams and barriers
-What are types of flooding?
Flash floods, others
-What are mitigation techniques for managing flooding events?
Like dams or barriers or drainage
-How does groundwater flow? What are recharge and discharge areas?
It flows through fractures in soil and rock due to gravity and pressure differences
Recharge: rainfall, snow melting, rivers, lakes, reservoirs,
Discharge; springs, streams, rivers, wetlands, lakes
-How is karst formed? What rock is dissolved? What are formations associated with karst topography?
Landscapes formed by dissolution of limestone, leading to caves and sinkholes
-What are coastal processes?
Controlled primarily by physical forces, such as tides, waves and windds, mainly on a local or regional scale
-What are coastal hazards?
Erosion and probably flooding
-How can we prepare for coastal hazards?
Global Climate
-How is solar radiation associated with surface environment? What is the albedo effect?
Solar radiation drives weather, climate, and energy for ecosystems. The albedo effect reflects light from surface
-What are greenhouse gases? How do greenhouse gasses warm the atmosphere?
CO2, CH4 trap heat, warming the atmosphere
-Where did our atmosphere and the oceans originate?
Some oxygen atoms formed water molecules and carbon dioxide. These molecules came out of the volcanoes as gases.
-What are ocean currents? How to they relate to the global climate?
Streams of water flowing constantly on the oceans surface in definite directions. Ocean currents regulate global climate, helping to counteract the uneven distribution of solar radiation reaching earths surface.
-How is glacial and interglacial cyclicity determined?
Driven by changes in the orbital pattern of the earth that have periods of about 20, 40, and 100 Ka
-How are ice cores used to determine the changes in atmosphere composition?
By drilling down into the ice sheet or glacier and recovering ice from ancient times
How are methane and carbon dioxide related to climate changes?
Methane is a potent greenhouse gas that has more than 80 times the warming power of carbon dioxide over the first 20 years after it reaches the atmosphere.
What are some of the consequences of climate change?
Rising temperatures, sea level rise, extreme weather, habitat loss
-What happened in past extinction events?
Severe Weather
-How do storms form? What is the differences between a hurricane and tornado?
From unstable air masses. Hurricanes form over warm oceans; tornadoes from severe thunderstorms.
Hurricanes: large, over water, sustained winds
Tornadoes: smaller, over land, rapid rotation
-What is thunder and lightning? How do they form?
Thunder us created when lighting passes through the air
-What are types of storms, i.e. winter storms?
Winter storms, thunderstorms, tropical storms, tornadoes
-What fuels storms? Hurricanes?
Heat energy
-How are tornadoes and hurricanes rated for damages?
Off of categories
-How does low and high pressure systems impact severe weather?
Low-pressure systems “suck” air into them. High-pressure systems have more air pressure than their surroundings.
-What are examples historical of severe weather events?
March 1993, the east coast of the u.s. had the coldest winter storm in u.s. history
-What are preparations for severe weather events?
Have food and water on hand
Fire
-What is drought and how is it related to fire?
It is when their is a shortage of water. It can cause the land to be very dry causing a small fire to turn into a huge one.
-What is the fire triangle?
Heat, fuel, and oxygen required for fire
-Why is fire beneficial?
Increases legumes in plant communities
-What are positive and negatives to suppression of fire?
Negative: can cause water damage to properties and equipment
Positive: immediate fire detection, rapid response
-What are precautions for building to prevent the spread of fire?
Firebreaks, fire resistant materials, controlled burns
-How does fire spread? What environments are climate conditions help or hinder the spread of fire?
I think partly because of wind spreading the ashes of fire itself.