NAU GLG 112 FINAL EXAM Questions and Answers(A+ Solution guide)

The type of magma associated with oceanic hot spots - mafic Decompression melting in this setting forms a long, submarine ridge - divergent boundary When mafic magma rising from the mantel rises through this type of crust, it will form int-felsic magma - Continental crust Shield volcanoes may form here, when magma upwells from the asthenosphere - hot spot The type of magma that most commonly forms at subduction zones - int-felsic magma This tectonic setting can form an explosive caldera - subduction zone or continental hot spot The current size of Yellowstone's magma chamber - 55 x 20 x 6 Mi This type of magma intrudes under Yellowstone and then becomes this type of magma over time - mafic, felsic This type of melting occurs within the mantle plume as hot rock rises to the surface - Decompression The type of melting that occurs when magma resides in the lithosphere - addition of heat An increase in this compound in magma will make the magma more viscous - Silica An increase in viscosity of magma allows the magma to trap more of this - GassesMost magma is generated here - Asthenosphere All magma begins as this composition - Mafic Magma is generated in subduction zones through addition of __________ - Volatiles Theses two factors affect magma viscosity - Silica content and temp The type of magma that can hold the highest concentration of dissolved gas - Felsic magma The magma comp that erupts at subduction zones - int-felsic magma This volcanic hazard causes structural roof collapse of homes and buildings - ash fall A hot mixture of ash, pumice, rock, and water - lahar Though not typically associated with casualties, this hazard completely devastates all in its path - lava flow The deadliest hazard associated with Pilnian eruptions - pyroclastic flow This hazard can complicate recovery when it combines with others, creating wet conditions - volcanic weather Ash ejected into the stratosphere will have this overall effect on regional climate - global cooling Another term for the slope of the land surface - gradient The entire area that a river drains - drainage basin or watershedTerm for smaller streams that contribute to larger streams - tributary This property of a stream increases toward base level - velocity, channel area, discharge or sediment load An increase in water velocity and channel size will cause an increase in this property - discharge The only stream characteristic that decreases downstream - maximum sediment grain size The lowest point in a drainage basin - base level Gradient is highest along this type of stream - headwater stream, or tributary, or straight stream Channel area is highest in this type of stream - trunk stream, or a stream located lower in the drainage basin/near base level The most common stream pattern that develops in drainage basins - dendritic pattern The location within the drainage basin where discharge will be the highest - near base level A sedimentary feature created by sediment deposition at base level - delta This type of flood reaches its peak discharge over several days - slow flood Heavy rain over a small drainage basin will create this type of flood - flash flood This Big Thompson Flood event and Hurricane Sandy Flooding had this weather condition in common - 2 systems colliding, BT:2 fronts formed a stationary T-storm, S: Hurricane + Noreaster metThis is a plot of recorded flood discharge over time - hydrograph One control on how fast a flood will rise and fall - basin size, # tribs, Soil sat levels, amt of rain/hour The relationship between air pressure and wind speed during a Hurricane - The lower the P, the higher the sustained wind speed (and storm surge) If Yellowstone erupts, this hazard will have most widespread affect on the people of the US and worldwide - ash Kilauea volcano is formed from this specific type of mafic magma - basalt The geologic term for that many people refer to as the Yellowstone "super volcano" - caldera