Geology; Chapter 7

hafodeko's version from 2016-11-14 03:31

Section 1

Question Answer
Name the three primary factors that affects that viscosity of magma.Composition, Temperature, Dissolved Gases
What provides the force to propel molten rock from the vent of a volcano?Escaping Gases
What is the most abundant gas found in magma?Water Vapor
The Hawaiian Islands consist primarily of what type of volcanic cone?Shield
Intrusive igneous bodies that cut across existing sedimentary beds are said to be ______.Discordant
Tabular igneous bodies formed when magma is injected along sedimentary bedding surfaces are ______.Sills
Igneous intrusive bodies with a surface exposure of more than 100 square kilometers are called ______.Batholiths
The area commonly called the Ring of Fire surrounds the ______.Pacific Ocean
Volcanoes located within the ocean extrude lavas that are primarily of ______ compostition.Basaltic
Subduction zone volcanism in the ocean produces a chain of volcanoes call an island ______.Arc
Basaltic lava with a surface of rough, jagged blocks is called ______.AA (the other is known as Pahoehoe)
Large amounts of volcanic material extruded from fractures in the crust are called ______.Fissures
______ are sheetlike intrusive igneous bodies the form when magma is injected into fractures the ut across rock layers.Dikes
Most of Earth's more than 800 active volcanoes are near ______ plate margins.Convergent
Rising plumes of hot mantle material produce intraplate volcanic regions a few hundred kilometers across are called ______.Hotspots

Section 2

Question Answer
Shape/Types of Volcanoes (in order by largest to smallest)Shield, Strato/ Compsite, Cinder
3 Zones of Igneous Activity:Divergent (sea floor spreading), convergent (deep ocean trenches), Intra-plate Igneous Activity (hotspots)
What is Extruded during Eruptions? (three)Gases(mostly water vapor), Lava, Pyroclastic
Four types of Pyroclastic:Ash, Pumice, Cinder, Block
Two types of Lava: AA, Pahoehoe

Section 3

Question Answer
Volcano:A mountain formed from accumulation of erupted materials
Crater: Steep walled depression located at any summit of many volcanoes
Vents: Pipe like conduit connection crater to magma chamber
Caldera: Unusually large (1+KM) summit depressions
Flank Vents:Smaller vents on sides of volcanoes
Fumaroles:Fissures/cracks from which only gases emitted
Lava Tube: Tunnel left after molten lava flows out
Glowing Avalanches: Glowing volcanic debris buoyed up by hot gases that move rapidly downslope (deadly)

Section 4

Question Answer
Dikes: Vertical sheets like bodies produced when magma is injected into fractures that cut across rock layers (discordant)
Sills: Horizontal skeet like layer injected in-between rock layer (concordant)
Laccolith: A massive igneous body intruded between pre-existent, may cause a dome
Batholith: A very large mass of igneous rock formed when magma was emplaced at depth
Divergent: Plates move apart, sea floor spreading (mid Atlantic ridge)
Convergence:Subduction zones, adjacent to deep ocean trenches.
Intra-plate Igneous Activity:Mantle plumes of basaltic magma. Hot Spots, Hawaii
Plutons:Underground igneous rock bodies
Discordant:(cut across existing layers, Perpendicular)
Tabular:(sheet like or massive)