Igneous Rocks
HW 3 - 2
1. How do igneous rocks form?
2. What page of the Earth Science Reference Tables describe how Igneous rocks form?
3. What are the two environments of formation?
4. What determines the texture of an igneous rock?
5. When referring to the texture of igneous rocks, what does coarse mean?
6. Where do extrusive igneous rocks form?
7. What is another name for extrusive rock?
8. Where do intrusive rocks form?
9. What is another name for intrusive rock?
10. Why are the textures so small in an extrusive rock?
11. Name the 5 minerals that may be found in Granite.
12. What does a rock have when the texture is “vesicular”?
13. Name the rock with a very coarse texture.
14. What does Rhyolite, Andesite and Basalt have in common?
15. Name 4 things that Basalt, Diabase and Gabbro have in common.
16. Felsic rocks are
in color,
density, and rich in
17. Mafic rocks are
in color,
density, and rich in
18. A student inspected five igneous rocks. Below is a description of her observations. Determine
the name of each rock based on her observations.
(a) Large, visible olivine and pyroxene minerals, ranging in size from about 1 mm to 5 mm, nonvesicular, and dark in color
(b) Light in color with a fine texture and contains gas pockets
(c) Fine texture, is composed only of Plagioclase feldspar, Biotite, and Amphibole
(d) Contains a very high amount of Potassium feldspar, has a glassy texture, but appears black.
(e) Has a glassy texture, gas pockets and is dark in color