Chapter 9 Volcanoes And Other Igneous Activity

Front 1

what are the 3 types of volcanoes, largest coming first

Back 1

1. shield- largest
2. composite
3. cinder cone-smallest

Front 2

what are shield volcanoes formed from?

Back 2

basaltic magma-low in silica

Front 3

shield volcanoes have what kind of eruptions and why?

Back 3

mild; because its low in silica

Front 4

layers of lava flow that solidfies and becomes rock-what volcanoe?

Back 4

shield

Front 5

composite volcanoes are what shape

Back 5

symetrical cone

Front 6

composite volcanoes are formed from what?

Back 6

granitic and andesitic magma= violent eruptions

Front 7

what volcanoe are the most deadly?

Back 7

composite

Front 8

composite volcanoes have what thrown into the air?

Back 8

pyroclastics

Front 9

what are pyroclastics?

Back 9

lava that solidfies

Front 10

composite volcanoes are made of 2 layers...

Back 10

1. rock
2. pyroclastics

Front 11

types of pyroclastics from composite volcanoes

Back 11

1. ash
2. cinder
3. block
4. bomb

Front 12

cinder cones are made out of

Back 12

cinders ( gravel sized pyroclastics)

Front 13

what volcanoes occur in swarms

Back 13

cinder cones

Front 14

higher silica, the more pyroclastics...t or f

Back 14

true

Front 15

what is a crater

Back 15

where lava comes out

Front 16

what is a caldera?

Back 16

when the opening of a volcanoe is greater than 1/2 mile across

Front 17

when oceanic crust descends beneath a continent, magma generated in the mantle rises to form what

Back 17

continental volcanic arc (Convergent plate volcanism)

Front 18

when an oceanic plate subducts, melting in the mantle produces magma that gives rise to what?....on the overlying oceanic crust

Back 18

volcanic island arc ie Aleutian Islands

Front 19

when an oceanic plate moves over a hot spot what is formed

Back 19

chain of volcanic structures ie Hawaiian Islands ( interplate volcanism)

Front 20

melting of the plume head (mantle plume) produces what

Back 20

flood basalts

Front 21

what volcanoe produces alot of pyroclastics and why?

Back 21

composite cones; because composite cones are formed from granitic and andesetic magma, which has a high silica content; the highter the silica content, the more pyroclastics.

Front 22

What is a mudflow made from ash and water called?

Back 22

lahara

Front 23

what is a pyroclastic flow not mixed with water?

Back 23

nuee ardente

Front 24

what does a nuee ardente consist of?

Back 24

ash and hot gas coming down from the volcanoe

Front 25

how fast does a nuee ardente travel?

Back 25

100mph; kills most people

Front 26

lava that flows through fractures in rock, compsed of basalt lava

Back 26

fissure flow

Front 27

rather than build cones, what usually emits fluid basaltic lavas that blanket wide areas?

Back 27

fissure eruptiions

Front 28

igneous rock that cooled in the pipe of the volcanoe

Back 28

volcanic neck

Front 29

When a volcanoe becomes inactive, what happens

Back 29

congealed magma often becomes preserved in the feeding conduit of the volcanoe as a cylinder mass, as weathering persists, the conduit is highly resistnat to weathering, may remain standing the surrounding terrain long after the cone has been worn away; volcanic necks

Front 30

what is plate tectonics?

Back 30

rigid part of the earth is moving around; is related to volcanic activity

Front 31

new crust is formed from what type of boundary?

Back 31

divergent

Front 32

tectonic plates are moving away from eachother (lava comes up tp fill gap)

Back 32

divergent

Front 33

plates are colliding, moving towards eachother

Back 33

convergent

Front 34

the tectonic plates go all the way down to the mantle...t or f...

Back 34

true

Front 35

the boundary in which basaltic magma comes from the mantle, and as it keeps going more and more basalt is made...

Back 35

divergent

Front 36

a convergent is also known as what...

Back 36

subduction zone

Front 37

one plate will go underneith the other, back to the mantle

Back 37

subduction zone

Front 38

During a subduction zone, one plate will go underneith the other, towards the mantle because the plate is more dense, what is that plate made of?

Back 38

basalt; density at 3.3

Front 39

what igneous compositions form the continental crust and why?

Back 39

granitic and andesitic, because it is less dense than basalt, so during a subduction zone, basalt will sink towars the bottom, and granitic/ andesitic will stay up.

Front 40

what igneous composition forms the oceanic crust and why?

Back 40

basaltic; because basalt is more dense than granitic/ andesitic compositions, there for it sinks to the bottom during a subduction zone.

Front 41

what are the 3 types of convergent boundaries?

Back 41

1. continental/oceanic
2. oceanic/oceanic
3. continental/continental

Front 42

what type of sediments are on top of the decending basaltic plate?

Back 42

felsic/intermediate (andesitic)

Front 43

continental/oceanic convergent boundaries produce what type of magma?

Back 43

granitic/andesetic; high in silica, compostie cones

Front 44

any body of intrusive igneous rock

Back 44

pluton

Front 45

what are the two pain types of plutons?

Back 45

tabular
massive

Front 46

2 types of tabular plutons

Back 46

dikes
sills

Front 47

type of tabular pluton that cuts across bedding planes; vertical

Back 47

dike

Front 48

type of tabular pluton that is parallel to bedding planes; horizontal

Back 48

sill

Front 49

book like pluton that can either be a dike or sill

Back 49

tabular

Front 50

types of massive plutons

Back 50

batholith
stock

Front 51

irregular shaped pluton

Back 51

massive

Front 52

massive pluton that covers more than 25 sq miles (form mt. ranges)

Back 52

batholith

Front 53

massive pluton that is less than 25sq miles

Back 53

stock

Front 54

igneous bodies are said to be what, if they cut across existing structures

Back 54

discordant

Front 55

igneous bodies are sad to be what if they are parallel to features such as sedimentary rock?

Back 55

concordant

Front 56

how are tabular plutons produced?

Back 56

when magma is forcibly injected into a fracture or zone of weakness, such as a bedding surface.

Front 57

what kind of body is a dike?

Back 57

discordant

Front 58

what kind of body are sills?

Back 58

concordant

Front 59

batholiths are typically composed of what types of igneous material?

Back 59

felsic and intermediate rock types

Front 60

lens shaped igneous body that lift the sedimentary rock surface

Back 60

laccolith