Rocks

Question 1

How do igneous rocks form?

Answer 1

From cooling and solidification of magma or lava.

Question 2

What’s the difference between intrusive and extrusive igneous rocks?

Answer 2

Intrusive = cooled underground (large crystals); Extrusive = cooled at surface (small/no crystals).

Question 3

Example of an intrusive igneous rock?

Answer 3

Granite

Question 4

Example of an extrusive igneous rock?

Answer 4

Basalt or obsidian.

Question 5

What are common minerals in igneous rocks?

Answer 5

Quartz, feldspar, mica, olivine, pyroxene.

Question 6

How do sedimentary rocks form?

Answer 6

From compaction and cementation of sediments.

Question 7

What are the three main types of sedimentary rocks?

Answer 7

Clastic, chemical, organic.

Question 8

What type of sedimentary rock is made from fragments of other rocks?

Answer 8

Clastic (e.g., sandstone).

Question 9

Which sedimentary rock forms from chemical precipitation?

Answer 9

Rock salt or limestone.

Question 10

What kind of rock is coal?

Answer 10

Organic sedimentary rock.

Question 11

What features are common in sedimentary rocks?

Answer 11

Layers (strata), fossils, ripple marks, mud cracks.

Question 12

How do metamorphic rocks form?

Answer 12

By heat and pressure altering existing rocks.

Question 13

What are the two types of metamorphism?

Answer 13

Contact (heat) and regional (pressure).

Question 14

What’s the difference between foliated and non-foliated rocks?

Answer 14

Foliated = banded layers; Non-foliated = no layers.

Question 15

What is marble’s parent rock?

Answer 15

Limestone

Question 16

What is gneiss’s parent rock?

Answer 16

Granite

Question 17

What is slate’s parent rock?

Answer 17

Shale

Question 18

What is the rock cycle?

Answer 18

The process where rocks change between igneous, sedimentary, and metamorphic types.

Question 19

Can one rock type turn directly into another?

Answer 19

Yes — any rock type can become another under the right conditions.