Igneous Rocks

Question 1

B. Intermediate/Andesitic Composition (2)

Answer 1

25 percent dark silicate minerals

explosive volcanic

Question 2

A. Granitic/Felsic Rock (2)

Answer 2

Continental Crusts,

Light

Question 3

C. Basaltic/Mafic Rock (3)

Answer 3

Ocean floor/volcanic islands,
Dark Silicates and calcium-rich feldspar
higher density than granite

Question 4

Felsic

Answer 4

Feldspar and Silica

Question 5

Mafic

Answer 5

Magnesium and Ferrum

Question 6

Ferrum

Answer 6

Iron

Question 7

D. Ultramafic Composition (3)

Answer 7

magnesium, iron, silicates (same as mafic)

Question 8

Ferromagnesian

Answer 8

iron/magnesium

Question 9

Fewer Large Crystals

Answer 9

Slow Cooling

Question 10

Many Small Crystals

Answer 10

Fast Cooling

Question 11

Glass (Obsidian)

Answer 11

very fast cooling

Question 12

Texture

Answer 12

Size Arrangement of Mineral Grains

Question 13

Vesicular Texture

Answer 13

Rapid Cooling, gas escapes through hole

Question 14

Aphanatic Texture

Answer 14

Fine grained, rapid cooling, some vesicles, rapid cooling

Question 15

Phanertic Texture

Answer 15

Coarse-grained texture, slow cooling, large visible crystals

Question 16

Porphyritic Texture

Answer 16

large crystals embedded in matrix of smaller crystals, multiple cooling rates, formed at different temperatures
two distinct grain sizes

Question 17

Pyroclastic Texture

Answer 17

Fragmental Appearance (like sedimentary rock)

Question 18

Pegmatitic Texture

Answer 18

Exceptionally coarse grained, formed in late stages of crystallization of granitic magmas

Question 19

Phenocrysts

Answer 19

Large Crystals

Question 20

Groundmass

Answer 20

Smaller Crystals

Question 21

Rhyolite has

Answer 21

glass fragments and seciles

Question 22

Rhyolite Texture

Answer 22

Aphanitic

Question 23

Rhyolite vs Granite

Answer 23

less common, less voluminous, extrusive

Question 24

Granite Composed of (3)

Answer 24

Quartz, Feldspar, Mica

Question 25

Granite Properties (4)

Answer 25

FelsicCoarse GrainedIgneousLight Colored Silicates

Question 26

Light Colored Silicates (2)

Answer 26

Quartz and Potassium Feldspar

Question 27

DARK Igneous Examples (5)

Answer 27

Ferromagnesium silicatesOlivinePyroxeneAmphiboleBoitite Mica

Question 28

Light Igneous Examples (6)

Answer 28

Non-Ferromagnesium silicatesQuartzmuscovitemicasfeldspars

Question 29

Texture of "Basalt"

Answer 29

Aphanatic

Question 30

Most Common Extrusive Rock

Answer 30

"asalt"

Question 31

"Basalt" Origin

Answer 31

Volcanic

Question 32

"Basalt" Composition (Igneous)

Answer 32

calcium-rich plagioclase feldspar

Question 33

Andesite Properties (2) IGNEOUS

Answer 33

Volcanic ORiginAphanitic Texture

Question 34

Diorite Texture IGNEOUS

Answer 34

Coarse Grained

Question 35

Plutonic (intrusive ingeous ) equivalent of andesite

Answer 35

diorite

Question 36

Rhyolite IGNEOUS Properties (3)

Answer 36

Extrusive equivalent of graniteMay contain glass fragments and vesiclesless voluminous and common than granite

Question 37

"Rhyolite" IGNEOUS Texture

Answer 37

Aphanitic

Question 38

"Obsidian" IGNEOUS Texture

Answer 38

dark/glassy

Question 39

"Pumice" IGNEOUS Properties (3)

Answer 39

frothy/voidsvolcanicglassy

Question 40

Granitic/Felsic Minerals (2)

Answer 40

Quartz/Potassium Feldspar

Question 41

Andesitic/Intermediate Minerals (2)

Answer 41

Amphibole/Plagioclase Feldspar

Question 42

Basalatic/Mafic Minerals (2)

Answer 42

Pyroxene/Plagioclase Feldspar

Question 43

Ultramafic Minerals (2)

Answer 43

Olivine, Pyroxene

Question 44

High Temp to Low Temp

Answer 44

Ultramafic->Felsic

Question 45

Continuous Series of Crystallization | BRS

Answer 45

Calcium Rich->Sodium Rich (Plagioclase Feldspar) | Ultramafic->Felsic

Question 46

Discountinuous Series of Crystallization (BRS)

Answer 46

Olivine, Pyroxene, Amphibole, Biotite (Ultramafic, Felsic)

Question 47

First to Crystallize

Answer 47

Olivine

Question 48

1/3 Magma Crystallized

Answer 48

Melt depleted in iron, mag, calcium