AS MAPPING
You will be given a
map which shows
some simple
geological
structures and
features to interpret.
There will also be
some questions
which relate to the
map and to the
rock, mineral and
fossil specimens.
The map will
have a key, a
scale and a
north arrow.
The key will include the
Rock Units shown on the
map. Sometimes you are
told what type of rocks each
rock unit represents but not
always. It is a good idea to
write the letters of each rock
unit on the map before you
start using it.
The key also tells you which
rock units have a specimen
available to study.
What type of folds are
these? What is the trend
and the symmetry of
these folds?
Folds
A
B
Folds
A
B
There are two folds on this map. What type
of folds are they? What is the trend and
the symmetry of these folds?
Unconformities mark
times when erosion is
dominant and no
sediments are deposited.
They mark a break in
deposition because of
uplift and mountain
building. The rocks above
overlay the rocks below
UNCONFORMABLY and
are often very different in
dip and strike.
Unconformities cut across other beds.
D
A
Folds
B
C
What type of fold
is this? What is
the trend and the
symmetry of this
fold?
Give the
geological history
of this map.
A
Unconformi
ties
B
D
C
Locate a fold
and an
unconformity on
this map.
Describe them
both fully.
Give the
geological
history of this
area.
A
Unconformities
B
Where are the unconformities on these
maps?
How can you be sure that they are
unconformities?
Unconformities
D
B
A
C
Locate two
folds and an
unconformity
on this map.
Describe them
both fully. Give
the geological
history of this
area.
Locate a fold and an unconformity on this
map. Describe them both fully.
Igneous
intrusions
B
A
What type of
igneous intrusions
are shown on this
map?
What rocks could
A and B be?
If faults are shown by straight lines then they
are vertical. If faults have a sinuous outcrop
then they are at an angle to the horizontal and
are probably reverse or thrust faults.
What type
B
of faults are
Faults
these?
What is the
F2
A
geological
C
history of
E
D
this area?
Faults
granite
What type of fault
is F2?
How do you
know?
Why does it
appear to be in
two sections?
Faults
The youngest rocks are always on the
downthrow side of a fault. You need to know
how old each rock is to find out the downthrow.
Faults
Strike-slip faults are vertical but the
movement on them is lateral (sideways). If
the far side moves to the right the sense of
movement is dextral, if it moves to the left the
movement is called sinistral. Which way has
this strike-slip fault moved?
What types of faults are
F1 and F2? How can
you tell?
E
Faults
D
A
Which one occurred
first? How do you
know?
What is the geological
history of this area?
B
C
Faults
F2
What types of faults are F1 and F2?
Which occurred first? How do you know?
A
B
Which fault F1 or
F2 is not vertical?
How do you know?
C
Which fault F1 or
F2 came first?
How do you know?
D
What is the
geological history of
this area?
E
Answer the
exam
question
about
locality 1 on
the map
above.
A
A
Using evidence from Map 2, give one reason
why this is a dyke rather than a sill.
What map evidence
would you need to know
to convince you that the
feature formed by Rock
B was a sill?
C
C
Sills
B
Graphic logs
Asymmetrical
ripples
Cross bedding
Erosional base
Give the evidence
from the graphic log
that shows that these
rocks were laid down
in a fluvial
environment.
Graphic logs
Complete the
log using the
descriptions
contained in
Table 2.
Complete this
table about F2.
Has the student got this geological history right?
Fossil
evaluation
A student identified this
fossil as being Fossil A.
Was this correct?
Fold wavelengths and amplitudes
wavelength
amplitude
Evaluation of fold axes
Are these
statements true?
• the fold trends
are NS
•the folds are
symmetrical
•the fold
wavelength is
200m.
What is the
Geological
D
geological
historyhistory
of this area?
A
B
G
E
F
C
Questions
State three pieces
of evidence, either
from Map 3 or your
fieldwork or
knowledge, which
confirm the
presence of an
unconformity.
Draw and label on
Map 3 the axial
planes of two folds
to the east of Fault
F2.
Rock unit B was deposited in tropical, shallow
seas. What evidence from the photo and the
graphic log would confirm this statement?
THE END