Download Volcanology Exam 2 Review: Questions and Answers and more Exams Advanced Education in PDF only on Docsity!
ERTH 111 - Exam 2 With
Complete Solution
A volcano is a constructional edifice formed from __________ and ____________. - ANSWER Lava, tephra
The melting temperature of magmas is primarily controlled by _________________________. - ANSWER Composition
The viscosity of magmas is primarily controlled by _________________________. - ANSWER All of the above: Degree of polymerization, Temperature, Volatile content
The ease of degassing in magmas dictates the ____________. - ANSWER Explosive potential
The type of volcano produced is primarily a factor of the _______________. - ANSWER Type of volcanic activity
Erupting magmas with a high amount of silica but low gas contents will produce ____________. - ANSWER Steep-sided domes
Erupting basaltic magmas with low gas contents will produce _____________, while basaltic magmas with high gas contents will produce ________________. - ANSWER Lava flows, fire fountaining
Phreatic eruptions occur as an external source of _____________ interacts with magma. - ANSWER Water
The eruption of many thin, runny lava flows will produce a ________________
volcano. - ANSWER Shield
A volcano type composed of a mixture of lava and tephra is a ________________ volcano. - ANSWER Strato or composite
A volcano type composed of all tephra is a ________________ volcano. - ANSWER Cinder cone
The eruption of thick, sticky lava flows with low gas will produce a ______________ volcano. - ANSWER Dome
If magma is withdrawn from a subsurface chamber it can produce a___________________. - ANSWER Caldera
A volcano that erupts only once is ________________ while a volcano that erupts multiple times is _______________. - ANSWER Monogenetic, polygenetic
A shield volcano is ________________ while a cinder cone is __________________. - ANSWER Polygenetic, monogenetic
Mt Rainier in Washington is not as conical as Mt Mayon in the Philippines due to later modification by _________________. - ANSWER Glaciers
An excavational, monogenetic volcano is a ___________________. - ANSWER Maar
An excavational, polygenetic volcano is a ___________________. - ANSWER Caldera
An constructional, steep-sided polygenetic volcano is a ___________________. - ANSWER Composite cone
An constructional, gentle-sided polygenetic volcano is a ___________________. - ANSWER Shield volcano
_______ western states. - ANSWER 11
_______________ are gravity-driven density currents. - ANSWER Ash flows
With __________, most of the material and momentum are concentrated at the base. - ANSWER Ash flows
__________ fill in topographic lows and can be strongly welded. - ANSWER Ash flows
__________ deposits are highly unsorted and can look like concrete. - ANSWER Ash flows
__________ are ground-hugging lateral blasts. - ANSWER Surges
___________________ are normally the most destructive and deadly to humans. - ANSWER Surges
______________ are thin deposits that show internal forms related to rapid horizontal flow. - ANSWER Surges
______________ result from fine ash that rises buoyantly above an ash flow. - ANSWER Co-ignimbrite lags
Explosive dome collapse can create _________________ events. - ANSWER All of the above (Ash Fall, Ash Flow, Surge)
The Soufriere Hills makes up the _______________ part of the island of Montserrat. - ANSWER South
Montserrat.is part of the Lessor Antilles which are formed by island arc volcanism as the ___________Plate is subducted under the _____________ Plate. - ANSWER Atlantic, Caribbean
Activity at the Soufriere Hills volcano began first as_________ in 1992, then later transitioned to _____________in 1995, and then finally ________________. - ANSWER Earthquakes, phreatic explosions, magma extrusion
The andesite magmas extruded in the Soufriere Hills volcano were about _____________ times more viscous than the lavas erupted at Kilauea. - ANSWER 1,000,000,
Steve Sparks discussed the origin of the dark inclusions found scattered in the andesite. He stated that the eruption was triggered by an influx of ______________magma which added heat, gases, and stirred up the andesite. - ANSWER Basalt
Vesiculation happens when _________. - ANSWER Bubbles form
Lava fragmentation happens when __________________. - ANSWER Bubbles burst
Lava fragmentation happens when ___________% vesicularity is reached. - ANSWER 70 - 80
Below the level of fragmentation magmas can be ____________. - ANSWER All of the above (Bubbly Liquids, Foam, Liquids)
The largest eruptions require ____________, ______________magmas. - ANSWER Volatile-rich, high-silica
The explosive release of dissolved gases can occur by _____________of magma. - ANSWER Rapid ascension
The definition of pyroclastic is " _________________________". - ANSWER Fire fragment
___________________ is fine glass pyroclasts under 2 mm. - ANSWER Ash
___________________ are pea to walnut sized pyroclasts. - ANSWER Cinders
___________________ are large, angular pyroclasts. - ANSWER Blocks
___________________ are large, aerodynamically sculpted pyroclasts. - ANSWER Bombs
______________ is a property not used to classify explosive eruptions. - ANSWER Eruption rate
________________ was the UH volcanologist who developed the classification scheme for explosive eruptions. - ANSWER George Walker
The classification scheme for explosive eruptions basically compares the_______________ of pyroclasts are to the ___________________ of the deposit.. - ANSWER Size, area
________________ eruptions form fire fountains as bubbly, low silica magmas decompress. - ANSWER Hawaiian
________________ eruptions are rhythmic bursts of larger bubbles in low silica magmas. - ANSWER Strombolian
ANSWER Non-explosive
The word lava comes from the Spanish verb lavar which means "_________". - ANSWER To wash
The most common geologic feature on the surface or the Earth and Moon are _______________. - ANSWER Basaltic lava flows
Flowing lavas form channels and tubes to conserve __________________. - ANSWER Heat
_______________ are a collection of lavas produced by the same eruptive event. - ANSWER Flow fields
The type of lava flow produced is controlled primarily by the ____________. - ANSWER Effusion rate
The effusion rate of pahoehoe lavas is ____________ than a'a lava. - ANSWER Lower
Pahoehoe lava are _____________ than a'a lava. - ANSWER Thinner
The chemical composition of Pahoehoe lava is _____________ a'a lava. - ANSWER About the same as
Pahoehoe lavas advance as _________ turn into __________which turn into __________. - ANSWER Buds, toes, lobes
The biggest difference between pahoehoe lava and a'a is the lava skin ________________ with a'a. - ANSWER Tears
In the video on pahoehoe lava there was ______________ in the can. - ANSWER Ravioli
Tearing of the cooling skin in a'a lava flows is a result of ___________________ behavior. - ANSWER Non-Newtonian
The cooling of the surface in lava channels to form lava tubes is analogous to _______________. - ANSWER Freezing rivers
A vegetated "island" of older substrate not covered by recent lavas is a(n)__________________. - ANSWER Kipuka
Lavas flowing from Kilauea since 1983 have all come from the ___________ Rift Zone. - ANSWER East
The narrator in the video on Hawaiian lava tube is the famous _______________. - ANSWER Ranger Dave
According to the Honolulu Advertiser article on Kilauea's Lower Puna eruption in 2018, the eruption rate exceeded ______________ cubic meters per second. - ANSWER 100
