Relative Dating – Stratigraphy Exercises
Complete the following block diagrams (A, B, C and D). Note that diagram A has been
completed as a sample. Label each rock layer, igneous intrusion, unconformity and fault with
letters and/or numbers. Finally, determine the correct order in which the various rock units
and other features occurred.
I might suggest using pencil crayons to keep rock layers organized.
1
2
3
4
5
6
7
8
9
10
11
12
13
B
C
E
F
A
H
G
I
J
K
B
B
D
C
B
Youngest
A deposited
Erosion angular disconformity
All younger layers tilted
B deposited
C deposited
D igneous intrusion
E deposited
F deposited
G deposited
H deposited
I deposited
J deposited
K deposited
Oldest
D
Note that this block diagram has already been labeled for you.
B
E.
1)
2)
3)
4)
5)
6)
7)
8)
F.
Draw the following stratigraphic sequence. I would suggest that you
complete the block diagram on a sheet of rough paper before
completing a good copy. Add letters to identify each layer (sometimes
you will need to label the layer twice if a fault cuts the sequence).
Unconformities should be shown with a wavy line. Colouring the layers
will make the diagram easier to understand. Use the following legend:
The entire sequence of rocks sits on top of an igneous pluton (a large piece of continental
crust).
A thin layer of sandstone is deposited followed by a layer of shale then a thick layer of
limestone.
The entire sequence is folded so that it forms and arch
centered on the middle
of the page.
Erode the entire sequence so that the surface layer is flat.
A thick layer of sandstone is deposited followed by a layer of limestone and a thin layer of
shale.
A fault dipping at about 45° cuts through the entire sequence. The fault tilts to the right.
The right side of the fault moves up and the left side moves down.
Erode the sequence so it is flat at the surface.
An igneous intrusion dipping at about 45° extends from the igneous pluton all the way to
the surface. The intrusion tilts to the left.
Extension Question. Draw your own block diagram (similar to questions A to D).
Provide the order of events that would produce your diagram.