Page numbers refer to: Geoscience (Edwards & King) = G,
Geological Science (McLeish) = GS, Earth (Press & Siever) = E
INTRODUCING IGNEOUS ROCKS AS
1
G54
How are igneous rocks formed?
2
G54
What is magma made of?
3
G54
What causes magma to crystallise?
4
G54 Explain how the randomly arranged crystalline texture of most
igneous rocks originates.
5
What are the grain size ranges used in the classification of igneous
rocks?
6
G55
7
G55 Use a diagram to illustrate what sort of igneous bodies you
would find the following crystal sizes in (include variation within
bodies):
a) Glassy
b) Fine
c) Medium d) Coarse
8
GS51 What does the TEXTURE of an igneous rock describe?
9
GS52 Using diagrams, describe & explain the origin of the following
textural features of igneous rocks:
a) Euhedral b) Subhedral c) Anhedral
d) Glassy
e) Equigranular
f)Porphyritic
g) Vesicular h) Amygdaloidal
10
GS50 Explain the use of the following terms describing the
composition of igneous rocks & state the essential rock forming
minerals in each group.
a) Acid
b) Intermediate
c) Basic
11
GS50 Describe & explain the colour index of Acid/Intermediate/Basic
igneous rocks.
What is the relationship between crystal size & cooling
12
Complete the Igneous Rocks Classification table
13
Complete full descriptions of the following rock types (including
Texture, Composition, Field relations)
a) Granite
b) Gabbro
c) Dolerite
d) Basalt
ESTA GEOTREX The Geology Teachers Resource Exchange Contributor: Ben Church
Establishment: Monmouth Comprehensive School Date: 05:06:05