Identification of igneous intrusions

Question 1

what are the different igneous intrusions one may identify?

Answer 1

batholiths, laccoliths, lopoliths, dykes and sills.

Question 2

what are intrusions?

Answer 2

forcing a body of igneous rock between or through existing formations, without reaching surface, composed of granite

Question 3

define the following:

batholiths

Answer 3

large dome-shaped intrusions of magma which occur at great depth beneath earths surface

Question 4

define the following:

laccoliths

Answer 4

mushroom shaped intrusions of magma, composed of granite

Question 5

define the following:

lopoliths

Answer 5

bowl shaped intrusions, composed of granite

Question 6

define the following:

dykes

Answer 6

vertical sheets of dolorites that form from magma

Question 7

define the following:

sills

Answer 7

horizontal layers of dolorites that form from magma

Question 8

what are contractual joints?

Answer 8

Joints that are formed when magma cools.

Question 9

what are off-loading joints?

Answer 9

Joints in granite that form when the weight of the material above is eroded