Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
109 Cards in this Set
- Front
- Back
|
What are natural hazards? |
Endangerment in the environment and can affect anyone anywhere |
|
|
What is vulnerability? |
Refers to the likelihood that a community will suffer injuries, death or property damage from a hazardous event |
|
|
What is a natural disaster? |
When I has her triggers vulnerability and the damage is so extensive that the affected community cannot recover through the use of its own resources |
|
|
When do hazards become disastrous? |
Only become disastrous when they overwhelm communities way to cope |
|
|
What is a Geohazard? |
A hazard post to people by the physical earth |
|
|
Who is the Roman god of fire? |
Vulcan |
|
|
What is a volcano? |
Conical, circular structure built by accumulation of lava flows and tephra(Volcanic ash) |
|
|
Where do volcanos occur at? |
1.Spreading/convergent plate margins (interplate) 2.intraplate volcanos (Not in association with plate boundaries) |
|
|
What are active volcanoes? |
A volcano that has a ruptured during the last 10,000 years and is likely to irrupt again |
|
|
What is an extinct volcano? |
a volcano that has not ruptured for tens of thousands of years and can never erupt again |
|
|
What are dormant volcanoes? |
Not erupted for 10,000 years or more, but could awaken again |
|
|
What are three main types of volcanoes? |
1.Stratovolcanos 2. shield volcanos 3.cinder cones |
|
|
What is a stratovolcano ? |
A large, potentially explosive cone shaped volcano composed of alternating layers of lava and pyroclast. |
|
|
What type of lava is a stratovolcano composed of? |
Felsic lava |
|
|
What are pyroclastic materials? |
Any fragmented solid material that is ejected from a volcano |
|
|
What is Ash (volcanic)? |
Find volcanic powder consisting of pulverize rock particles and solidify droplets of lava |
|
|
What is a shield volcano? |
A broad, dome volcano form from many layers of basaltic lava. -Much larger than stratovolcano’s |
|
|
What is a Cinder cone volcano? |
A small, cone shaped volcano consisting of pyroclastic that settle at the angle of repose |
|
|
What is the angle of repose? |
Steepest angle at which loose sediments can settle |
|
|
What are Cindercone volcano is built out of? |
Build from small pieces of red or black basalt |
|
|
What are three main types of volcanic products? |
1.Lava 2.pyroclast 3.gases |
|
|
What are three types of lava? |
1.Mafic 2.intermediate 3.felsic |
|
|
Mafic Lavas have ____viscosity and flow____ |
Low; easily |
|
|
Felsic lavas have _____viscosity with ____ability to flow |
Low; restrictive |
|
|
What is the Viscosity? |
The extent to which a fluid resists a tendency to flow |
|
|
A shield volcano containing mafic lava would have ____viscosity and flow____ |
Low viscosity; flow easily |
|
|
A stratovolcano with plug dome would have ____Viscosity and flow_____ |
Low viscosity; restricted flow |
|
|
What is a Pahoehoe? |
When mafic lava solidifies into smooth, bilowly lobes over the surface |
|
|
What is ‘A’a? |
When mafic lava cakes on a blocky, rough surface |
|
|
The higher the silica content the ______viscosity |
Higher |
|
|
What are four types of pyroclasts(tephra)? |
1.Ash 2.bombs 3.Lapilli 4. blocks |
|
|
What is the smallest type of pyroclast? |
Ash |
|
|
What is the largest type of pyroclast? |
Blocks |
|
|
What is lapilli? |
Marble to golf ball sized cooled fragments of lava |
|
|
What is a bomb ( volcanic)? |
A streamlined fragment of lava ejected from a volcano that is cold and hardened as it moved through the air |
|
|
What is a block ( volcanic)? |
Fragment of rock from the volcanos cone that is ejected during an explosive irruption |
|
|
What is a pumice? |
A lightweight porous rock with at least 50% air content, form from felsic lava |
|
|
What is the driving force that causes most volcanic eruptions? |
Volcanic gases |
|
|
What are 5 main volcanic gases? |
1.Water vapor 2.sulphur dioxide (S02) 3.carbon dioxide (C02) 4.hydrogen sulphide (H2S) 5.hydrogen halides (HS, HCl, HBR) |
|
|
What does sulphur dioxide causing the atmosphere? |
Global cooling |
|
|
What does carbon dioxide causing the atmosphere? |
-Global warming -trapped in low-lying areas can be lethal to people and animals |
|
|
What main gas committed by volcanos is very toxic and high concentrations? |
Hydrogen sulphide (H2S) |
|
|
What are four common volcanic landforms? |
1.Volcanic mountains 2.columnar jointing 3.large igneous provinces 4.calderas |
|
|
What is columnar jointing? |
A geometric pattern of angular columns that forms from joints in basaltic lava during cooling |
|
|
What are joints? |
A crack or weak plane and rock |
|
|
What are large igneous provinces? |
An accumulation of flood basalts that covers an extensive geographic area |
|
|
What is it caldera? |
A large depression that forms when a volcano is magma chamber empties collapses after the volcano irrupt’s |
|
|
What type of volcano is now a large caldera in wizard island? |
Cindercone |
|
|
What are two kinds of volcanic eruptions ? |
Effusive and explosive |
|
|
What is an effusive eruption ? |
A nonexplosive irruption that produces mostly lava (example shield volcanoes) |
|
|
What is an explosive erruption? |
Interruption that sends rock, Ash and volcanic gases high into the troposphere, or even into the stratosphere |
|
|
How is Volcano strength ranked ? |
The volcanic explosivity index (VEI) -Scale of 1 to 9 -Ranks volcanic irruption magnitude based on the amount of the material of volcano ejects during an irruption |
|
|
What are the two greatest volcanic threats? |
1.Lahar 2.pyroclastic flow |
|
|
What is a lahar? |
A thick slurry of mud, Ash, water and other debris that flow rapidly down to snowcap stratovolcano when it erupts |
|
|
What is pyroclastic flow? |
A rapidly moving avalanche of searing hot gas and Ash |
|
|
What are causes for lahars? |
-rapid melting of snow and ice by pyroclastic flow’s ( primary) -Intense rainfall on loose volcanic rock deposits -Break out of a lake damned by volcanic deposit -Debris avalanche |
|
|
What’s another word for pyroclastic flow? |
Nuee ardente |
|
|
What characterizes pyroclastic flow? |
Outburst of hot gases and dust caused by a blocked vent |
|
|
How many fatalities were there in the destruction of Pompeii? |
16,000 people died (Mount Vesuvius erupted) |
|
|
Can scientist predict volcanic irruption’s? |
Scientist can sometimes predict in a ruptured within weeks or months if a volcano gives warning signs |
|
|
What are some signs that magma is moving upward in the magma chamber? |
1.Gases 2.widening cracks 3.swelling 4.earthquake activity |
|
|
What is the most active volcano in the cascade range? |
Mount Saint Helens |
|
|
What percent of the Pacific oceans margins are subduction zones with active/dangerous stratovolcano is? |
Greater than 60% |
|
|
What are the most common type of volcano Found in the Pacific Ring of fire? |
Explosive strato volcanos |
|
|
Most earthquakes occur along plate boundaries in_____ |
Seismic belts |
|
|
What are three types of faults? |
1.Normal 2.reverse 3.strike slip |
|
|
What is a normal fault? |
The result of tensional for us as to four blocks move apart, causing one for block to slip down words in relation to the other fault block |
|
|
What is a reverse fault? |
The result of compressional force as two fault blocks are pushed together, causing one block to move upward in relation to another block |
|
|
What is a strike slip fault? |
The result of shearing force us as one block move horizontally in relation to another block |
|
|
What percentage of the earth earthquake energy is released in the Pacific Ring of fire,Where plates are subducting? |
80% |
|
|
What do you reverse a normal faults create that results from vertical movement of the fault blocks? |
Fault scarp or cliff face |
|
|
What is faults scarp? |
A cliff face resulting from the vertical movement of a reverse or normal fault |
|
|
Where is strike slip fault Crosslin your features, those features may be ____ by fault movement |
Offset |
|
|
How do earthquakes occur? |
-When geologic stress exceeds friction, and the crust brakes (either along or pre-existing fault or along a new fault) and the blocks move -The build up strength energy is released and travels to the crust is seismic waves, resulting in an earthquake |
|
|
What is focus (Hypocenter)of an earthquake? |
The location of the initial movement along a fault during an earthquake |
|
|
What is an epi- center? |
The location on the ground surface immediately above the focus of an earthquake, where earthquake intensity is usually the greatest |
|
|
What is foreshock? |
A small earthquake that sometimes proceeds a larger earthquake |
|
|
What is aftershock? |
A small earthquake that follows the main earthquake |
|
|
What are two types of seismic waves? |
1.Body waves 2.surface waves |
|
|
What are body waves? |
Pass through the body of earth (P waves and S waves) |
|
|
What are surface waves? |
Travel near the surface of the cross (R waves and L waves) |
|
|
What is a seismograph? |
An instrument used to detect, measure, and record ground shaking |
|
|
Which type of waves produce the largest ground shaking? |
L waves and are waves |
|
|
Which waves arrive first ?which waves arrive last? |
-P waves arrive first - S waves follow P waves -Rwaves and Lwaves are the last to arrive |
|
|
What are two categories of seismic waves based on how waves move? |
1.Compressional waves 2.shear waves |
|
|
P waves are in what category of seismic waves based on how waves move? |
Compressional waves |
|
|
S waves are in what category of seismic waves based on how waves move? |
Shear waves |
|
|
R waves are in what category of seismic wave? L waves ? |
Compressional; shear |
|
|
What are compressional waves? |
Produce movement that goes back-and-forth in a direction parallel to the direction of travel in waves |
|
|
What are sheer waves? |
Move back-and-forth perpendicular to the direction the waves are travelling |
|
|
How is earthquake magnitude determined? |
From measurements of ground movement using seismographs |
|
|
What does the Richter scale measure? |
Quantifies magnitude of local ( California) earthquakes |
|
|
Who developed the Richter scale? |
Developed in 1935 by Charles F Richter |
|
|
What scale used as a decimal scale (logarithm to the base of 10) of maximum single wave amplitude recorded or not then standard seismogram at a distance of 100 km from the Eppy center? |
Richter scale |
|
|
The amount of ground shaking depends on what three factors? |
1.The earthquakes magnitude 2. the distance from its focus 3.the composition of the ground being shaken |
|
|
What is earthquake intensity? |
Determined by the amount of damage in earthquake causes to a physical structure |
|
|
What is the modified Makalli intensity scale (MMI)? |
And earthquake ranking system based on damage done to structures (uses Roman numerals) |
|
|
What is the earthquake ranking system based on the amount of ground movement? |
The moment magnitude scale |
|
|
____magnitude events occur less frequently than ____magnitude events |
High ;low |
|
|
What is liquefaction? |
The transformation of sod sediments into an unstable slowly as a result of ground shaking during an earthquake |
|
|
What type of sediments are susceptible to liquefaction? |
Loose, wet sediments |
|
|
How many deaths were there in the 2009 l’Aquila earthquake |
309 deaths,Destroyed or damaged thousands of buildings |
|
|
In the 2009 Italy earthquake why were seven members of the Italian national commission forecast and prevention of major risk tried for? |
In accurate, incomplete and contradictory statements |
|
|
The controversy of the 2009 Italy earthquake was centred around what three comments made by the civil servant? |
1.The situation was certainly normal 2.pose no danger 3.the scientific community continues to assure me that to the contrary it’s a favourable situation because of the continuous dischargecharge of energy |
|
|
Where are the worlds deadliest volcanos found? |
-In the sunda arc, indonesia |
|
|
What are the three worlds deadliest volcanos found in Indonesia called? |
1.Krakatau 2.Toba 3.Tambora |
|
|
When was Krakatau’s most recent irruption and how many people did it kill? |
1883 (VEI of six irruption killed over 36,000 people) |
|
|
What volcano has the greatest know when human death toll? |
Tambora 1815 (92,000 casualties) |
|
|
Why was the year of 1816 nicknamed “the year without a summer”? |
It was unusually cold in both eastern North America and in northern Europe due to Tambora’s wide reach |
