Internal / External Processes Create? Major External Processes Driven by energy from the sun and from gravity. Also create hazards and resources.

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1 ES 10 September 2018 Geologic Processes and Hazards Geology: scientific study of Earth s materials and processes Materials: what are these, list as many as you can External & Internal Processes: list several of each Geolologic/Processes Study Guide Practice all definitions, define geology List / discuss examples of all internal & external processes Understand general concepts of Plate Tectonics: SFS, plate boundaries, locations, examples, associated geologic hazards and resources Discuss / describe common Geologic Hazards (focus on E-quakes, Tsunamis, volcanoes, and Mass Wasting) Earthquakes Key Terms: focus, epicenter, describe types of waves, outcomes, damage a function of, prediction Damage from E-Quakes, a function of what? What can we do to reduce damage? Make a list here for each one. What causes Tsunamis? Why called shallow water waves? Where most likely to occur? Main causes of Mass Movement? How do humans make things worse? Why Santa Cruz Mountains so susceptible? Also look over Volcanoes, relationship to volcanoes, mass wasting and tsunamis Major External Processes Driven by energy from the sun and from gravity. Also create hazards and resources. Hydrologic Cycle Weathering and Erosion Deposition and Soil Formation Glaciers, Rivers and Streams, Flooding Mass Movement (landslides, rock falls) Land-Sea Interactions/Coastal Erosion Major External Processes change the Earth s surface annual transfer rate in thousands of cubic kilometers The Hydrologic Cycle Weathering and erosion Deposition and Soil Formation Glaciers, Rivers and Streams Mass Movement (landslides, rock falls) Land-Sea Interactions/Coastal Erosion Major Internal Processes Driven by energy (heat) in the Earth s interior Convection and Plate Tectonics Internal / External Processes Create? Hazards and Resources Rock Deformation Crystallization Metamorphism Overlaps? E-quakes, volcanoes Think about Plate Tectonics: Definition Boundaries = Geologic Activity 1

2 Plate Tectonic Study Guide / Key Concepts Define Plate Tectonics What is the lithosphere? What is the Asthenosphere? What are they each composed of? Name the 3 types of plate boundaries and describe the motion associated with each. Define the process of Sea Floor Spreading? How do scientists know SFS is occurring. What is subduction? Where does it occur? List a few examples of where each types of boundary is located. Plate Tectonic geography is important. List a few examples of continental margins that are 1,000 s of miles away from the nearest plate boundary. These are called Passive. What types of geologic activity are associated with lithospheric plate boundaries? This is important, list as many as you can. Geologic Hazards Result from a combination of internal and external processes. Examples include? 1. Earthquakes 2. Tsunamis 3. Volcanoes 4. Mass Movement 5. Coastal Erosion / Flooding / Rising Sea Level 6. Fluvial Systems /Flooding (Later in the Course) Earthquakes Over a million fatalities from earthquakes in the last 10 years. What are the hazards / outcomes? Ground Shaking: collapse of buildings, roads, bridges landslides, liquefaction, land subsidence, Fire: broken gas and power lines Flooding: tsunamis and/or co-seismic subsidence Ground Displacement: structures lying across fault aka Hypocenter Major dangers are from human-made structures rather than the earthquake itself. Ground shaking: collapse of a parking structure during 1994 Northridge earthquake. Earthquake events: Landslides 10/17/89 2

3 San Francisco 10/17/89 San Francisco burning after the 1906 earthquake. Liquefaction Foundation Foundation; bedrock, sand, mud Liquefaction in Monterey Bay, 10/17/89 Types of Earthquake Waves: Surface and Body A.E.H. Love, an British Mathematician in 1911 Love Waves Body Waves Help determine earthquake strength and location Sir John William Strut, aka Lord Rayleigh, a British Physicist in

4 Amount of damage controlled by what? 1) Strength 2) Relative Proximity 3) Foundation 4) Building Type / Codes Italy August 23 rd , ~290 fatalities Fig. 9-15, p.260 Building Type / Codes Turkey 8/17/1999 >17,000 fatalities, 7.6 magnitude, 37 sec shaking, 500,000 homeless ~ Mud and brick buildings in Bam Iran did not comply with earthquake standards Earthquake: Central CA, SLO County Southeastern Iran, Bam Date: 12/22/03 12/26/03 Magnitude: Depth: 7.6 km 10 km Tectonic Transform Convergent Setting: Population: 239, ,000 Casualties: 2 >43,000 Injuries: 40 ~30,000 Damages: 40 buildings 60% of all collapsed; small fires; buildings power outages destroyed 4

5 Napa Earthquake, 6.1 on 8/24/14 Reducing Earthquake Hazards? Locate active faults Map high risk areas Better land-use planning Better building codes Better prediction both on land and in the worlds oceans. Improved global seismic sea wave warning system Noon? ES 10 September 2018 Geologic Processes and Hazards Geology: scientific study of Earth s materials and processes Materials: what are these, list as many as you can External & Internal Processes: list several of each Tsunami vs Tidal Wave vs Seismic Sea Wave Where does most Geologic Activity occur? Tsunamis Seismic Sea Waves Triggers / Cause (4) Speed, height, period, wavelength Trough often arrives first Tsunamis 15 min Volcanoes 5 min Mass Wasting 10 min Fig , p. 321 Historical Tsunami Events and Resulting Fatalities 230, Indian Ocean earthquake with tsunami 12/26/ , Lisbon earthquake, tsunami, earthquake and fire, Portugal and Morocco 100,000 - Awa, Japan, ,000 - Messina, Italy, earthquake and tsunami, ,000 - South China Sea, 1782, including deaths in Taiwan 36,000 - Krakatoa volcano explosion, ,000 - Tokaido-Nankaido, Japan, ,000 - Japan, ,674 - Chile, ,070 - Sanriku, Japan, ,850 Japan, 3/11/11 (~3,287 missing) 15,030 - Southwest Kyushu, Japan, ,486 - Ryukyu Trench, ,233 - Tokaido-Kashima, Japan, ,000 - Nankaido, Japan, ,000 - Moro Gulf, Philippines, ,000 - Papua New Guinea, ,008 - Sanriku, Japan, ,000 - Chilean Earthquake, deaths in Chile, U.S. (Hawaii), Philipines and Japan Aleutian Island earthquake, deaths in Hawaii and Alaska, U.S., Good Friday Earthquake, Alaska and Hawaii, U.S.,

6 Japan Earthquake Tsunami Seacliff State Beach, Aptos, CA 3/11/11 Capitola California March 11, 2011 Santa Cruz Yacht Harbor, California Reducing Tsunami Hazards? Warning system in all major oceans Better Land Use Planning Local gov t evacuation routes and procedures Education about warning signs Ground-shaking in coastal areas Unusual disturbance of ocean, drop in SL Move to high ground (several hours-days) First wave generally not largest Volcanoes Volcanoes: landforms created when magma escapes from Earth s interior through vents or Earth s surface and becomes lava. Lava cools and solidifies around vents forming volcanic rock. Globally, ~50 volcanoes erupt each year. Located at both convergent and divergent plate boundaries (not transform) and interior plate hot spots. 6

7 Hazards Volcanic materials burry and destroy habitats and property; toxic gases (acid rain) Lahars (volcanic mudflows formed from sudden ice melting) Tsunamis Volcanism Benefits Release of gases and water vapor forming atmosphere and hydrosphere Addition of fertile soils Addition of real estate (Hawaii, Pacific Islands, Iceland) Geothermal energy Info about Earth s interior Reducing Volcanic Hazards? Map high risk areas Volcanic zoning (no development in volcanically prone areas) Better prediction (monitor volcano s surface, temperature, gas release, seismic activity) Effective evacuation plans Successful case histories: Mount Pinatubo Philippians, Mount St Helens, Oregon brave-boiling-waters-capture-drama-searing-hot-lava-crashing-seas- Hawaii.html Mass Movement Main Causes: Water, Seismic Activity, Volcanoes, Humans: Slumps / Slides Mudflows, Earthflows Rock Falls Lahars (volcanic) Debris Flows Avalanche 08/la-conchita-landslide-verdict.html Southern Italy Landslide 2/16/ m wide, 330 m long, and >30 m deep, with an estimated volume of 1.3 million cubic meters. La Conchita

8 La Conchita 1/10/05 La Conchita 1/10/05 Irrigation Water leakage: septic tanks other utilities Surface water diversion Road construction Mining operations Logging Fires Excavation of slope Mass Movement Triggered by human activities Mass Movement Santa Cruz Mountains especially susceptible Topography Geology (Dip Slopes) Rocks: soft fractured, folded, faulted Rainfall, El Niño winters Earthquakes Wildfires SOLUTIONS? California rainstorms Volcanism Mass Movement Tsunamis The Hawaiian Islands: a combination of volcanism, slope failure and mega-tsunamis 8