1: Rocks

Question 1

What is a rock?

Answer 1

an aggregate of minerals and/or a mass of glass

Question 2

How are igneous rocks formed?

Answer 2

formed by the soldification (cooling) of molten rock material (magma)

Question 3

Igneous rocks environments of formation?

Answer 3

• Underground (intrusive/plutonic)

- Surface (extrusive/volcanic)

Question 4

The texture of an igneous rock depends on the…

Answer 4

Cooling rate.

Slow cooling – Granite (coarse-grained) -> Rhyolite (fine-grained) -> Obsidian (glassy) – Fast cooling

Question 5

To see if the igneous rock was above ground or under ground you look at the…

Answer 5

Grain size.

Question 6

Extrusive (volcanic) Igneous Rocks

Answer 6

Basalt, Andesite, Rhyolite

Question 7

Basalt

Answer 7

• Extrusive Igneous
• All over the solar system
• Air pockets - when this was magma there were bubbles floating around in it

Question 8

Andesite

Answer 8

• Extrusive Igneous
• Not that common
• Finer grain texture
• Composition wise it is the same stuff as Diroite

Question 9

Intrusive (plutonic) Igneous Rocks

Answer 9

Peridotite, Gabbro, Diorite, Granite

Question 10

Peridotite

Answer 10

• Most abundant rock under the planet
• Make salt by melting peridotite a little bin the the mantel
• Made up of olivine

Question 11

Gabbro

Answer 11

• Made up of pyraxene and other white minerals

- Pretty common rock

Question 12

Diorite

Answer 12

• Amphabole

- Not that common

Question 13

Granite

Answer 13

One of the most common rock in the continental crust

Question 14

Igneous intrusions

Answer 14

Dikes, Plutons, Batholiths

Question 15

Dikes

Answer 15

Tabular intrusions that cut across structures in adjacent rocks

Question 16

Plutons

Answer 16

Irregular or blob-shaped intrusions ranging from tens of meters to tens of kilometers across

Question 17

Batholiths

Answer 17

Vast areas intruded by numerous plutons

Question 18

Why are intrusive rocks now exposed at the surface?

Answer 18

• Crust is being eroded away on the mountain chain

- Uplift is bring up the pluton

Question 19

Sedimentary rocks are what percent of rocks at Earth’s surface?

Answer 19

75%

Question 20

How are most sedimentary rocks are composited

Answer 20

They are mostly stratifed (layered)

Question 21

Two types of sedimentary rocks

Answer 21

Detrital (clastic) and Chemical

Question 22

How are Detrital (clastic) sedimentary rocks formed?

Answer 22

formed from fragments of pre-existing rocks

Question 23

How are Chemical sedimentary rocks formed?

Answer 23

formed from minerals precipitated from water

Question 24

Mud grain size/rock(s)?

Answer 24

• Feels smooth on teeth
• Mudstone
• Shale - if splits along thin layers

Question 25

Silt grain size/rock(s)?

Answer 25

- Feels gritty on teeth | - Siltstone

Question 26

Sand grain size/rock(s)?

Answer 26

- Visible grains to 2mm | - Sandstone

Question 27

Gravel/Boulders grain size/rock(s)?

Answer 27

- Visible grains more than 2mm - Conglomerate - if fragments are rounded - Breccia - if fragments are angular

Question 28

List of Chemical Sed Rocks?

Answer 28

Rock salt, Gypsum, Limestone, Coal

Question 29

Rock salt - origin/other features

Answer 29

- Evaporation of sea or saline lake water | - light-colored, tastes salty

Question 30

Gypsum - origin/other features

Answer 30

- Evaporation of sea or saline lake water | - light colored, soft

Question 31

Limestone - origin/other features

Answer 31

- Precipitation of calcium carbonate from sea or lake water | - Gray, fizzes in acid (calcite), may contain fossils

Question 32

Coal - origin/other features

Answer 32

- Buried plant material | - black, may contain plant fossils, burns

Question 33

Define metamorphic rock

Answer 33

Rocks which have been changed by effects of heat and pressure

Question 34

metamorphic rock: effects of heat

Answer 34

- Recrystallization | - sometimes new minerals are grown

Question 35

metamorphic rock: effects of pressure

Answer 35

- Deformation - Foliation, aligned mineral grains - Folds, usually contorted foliation

Question 36

List of metamorphic rocks

Answer 36

Slate, Schist, Quartzite, Marble, Gneiss

Question 37

Slate features and was originally what rock?

Answer 37

- fine-grained, splits into thin sheets | - originally shale

Question 38

Schist features and was originally what rock?

Answer 38

- coarse-grained, sparkly | - originally shale

Question 39

Quartzite features and was originally what rock?

Answer 39

- coarse-grained, very hard | - originally sandstone

Question 40

Marble features and was originally what rock?

Answer 40

- white, fairly soft, fizzes in acid | - originally limestone

Question 41

Gneiss features and was originally what rock?

Answer 41

- coarse-grained, light and dark bands | - originally a wide variety of rocks

Question 42

Rock Cycle (full circle)

Answer 42

- Magma -- cooling -- Igneous Rocks - Igneous Rocks -- upflit -- Weathering and Erosion - Weathering and Erosion -- Deposition -- Sediments - Sediments -- burial and lithifiaction -- Sedimentary Rocks - Sedimentary Rocks -- heat and pressure -- metamorphic rocks - metamorphic rocks -- melting -- magma

Question 43

Rock Cycle (inner circle)

Answer 43

- Igneous rocks -- heat and pressure -- Metamorphic Rocks - Metamorphic Rocks -- Uplift -- Weathering and Erosion - Sedimentary Rocks -- Uplift -- Weathering and Erosion