GEOLOGY STUDY GUIDE
Module exam GL1 June 2005
FOSSILS
Geology Department, Greenhead College, Huddersfield.
Silurian trilobite Calymene from Wenlock Limestone, Dudley
Your name ……………………………………………………………
Date ………………………….
LEARNING TARGETS
margin notes
When you have completed this study guide, you will:
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Understand the principle of Uniformitarianism
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Have learnt the morphology of ammonites, trilobites, corals, plants,
graptolites, bivalves and brachiopods
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Know about the evolutionary changes of cephalopods and graptolites
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Understand how fossils are preserved in rocks
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Be familiar with the ideas of life and death assemblages and derived fossils.
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GEOLOGY STUDY GUIDE
Module exam GL1 June 2005
Resources
Here is a choice of resources to use. You do not need to look at them all but clearly the more you read the
better your knowledge of case studies will be. Tick the box once you have used the resource.
If you read a photocopied extract then highlight it to help you reread it for revision. If you make notes
from a video tape make sure that the notes are headed with the name of the tape so that you know the
source of your information.
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FOS1
FOS2
FOS3
FOS4
FOS5
FOS6
FOS7
FOS8
FOS9
FOS10
FOS11
FOS12
FOS13
FOS14
FOS15
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FOS16
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Websites
www.geolsoc.org.uk/ Go to Teaching Resources
www.ucmp.berkeley.edu/ordovician/ordostrat.html
www.brookes.ac.uk/geology/8361/1998/kirsty/trilo.html
www.uky.edu/KGS/coal/webfossil/pages/silurian.htm
www.mpm.edu/reef/intro.html
geology.about.com/science/geology/cs/
www.trilobites.info
Understanding Geology David Webster p 119-136
Geoscience Edwards and King p 100-107
Geological Science by Andrew McLeish p 188-228
Powerpoint of Rock Record and present-day environments
Diagrams of fossil groups to be annotated
Powerpoint of fossil preservation
Notes on fossil preservation
Handout on moulds and casts
Powerpoint of life and death assemblages
Christmas Lectures 1995 Tape 12, 19mins
Library Nield and Tucker Palaeontology: An Introduction
Library Fortey, Richard Fossils
Library Geological Museum British Fossils
Library Halstead, L.B. Hunting the Past
Video Life on Earth Tape 22 Bivalve and Brachiopod evolution 11 mins
Life on Earth Tape 22 Ammonoid evolution 5mins
Video Fossils as Clues to Past Environments Tapes 57 and 61 22 mins
There are many other websites you could search.
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GEOLOGY STUDY GUIDE
Module exam GL1 June 2005
ACTIVITY 1 : FOSSIL MORPHOLOGY
Margin notes
TASK 1 UNIFORMITARIANISM
The Principle of Uniformitarianism states that the present is the key to the past.
What do you understand by this statement?
Watch the powerpoint FOS 4. Make lists of examples in columns, which are
headed as follows:
environment of deposition
Rock Record examples
present examples
Catastrophism is the idea that many geological processes are sudden and largescale. From the slides you have seen to what extent do you think that this idea is
valid?
Watch FOS 16 to relate fossils to past environments.
TASK 2 MORPHOLOGY OF FOSSILS
Fossils represent evidence of former life preserved in rocks.
1. Brainstorm as many examples as you can of the types of evidence for
organisms that geologists look for in rocks.
2. What does the phrase trace fossil mean? Give some examples.
3. What does morphology mean?
FOS 5 will help you learn about the morphology of these groups of fossils:
brachiopods, bivalves, ammonites, corals, graptolites, trilobites, plants
In class we will label their features and comment briefly on their mode of life.
TASK 3 BRACHIOPODS AND BIVALVES
These organisms are both molluscs with two shells (or valves). There are some
similarities between them but the differences are more important. These are the
features you need to be able to recognise for each fossil group.
Use FOS 5 to label and learn these features.
Brachiopods
shell shape
symmetry
pedicle valve
brachial valve
pedicle opening
umbo
hinge line
adductor muscle scars
diductor muscle scars
Bivalves
valve shape
symmetry
muscle scars
hinge line
teeth and sockets
gape
pallial line
pallial sinus
umbones
Now carry out a practical to learn how to identity some features on real fossils.
Observe at least four of each group. Some of the bivalves you should study are
present-day shells found on beaches. They show bivalve features better than most
fossils.
Use this box for notes
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GEOLOGY STUDY GUIDE
Margin notes
Module exam GL1 June 2005
TASK 4 AMMONITES
These are part of the cephalopod group of molluscs. The evolutionary changes that
cephalopods have undergone over time have been dramatic. We will discuss these
changes in class and show how their morphology has changed. The parts you need
to recognise in a practical are these:
shell shape, symmetry, suture lines, chambers, septa, keel
TASK 5 CORALS
Corals are an important group at present as they make up large coral reefs in warm
waters around the world today. Different species of colonial corals have been very
significant in the past as reef-building fossils and are useful for geologists in many
ways. In particular they indicate that the environment of deposition is marine,
warm water with high energy wave action.
Look at some specimens of fossil and present corals and learn the features which
make them distinctive.
septa, colonial corals, single corals
TASK 6 GRAPTOLITES
Graptolites are an extinct group of organisms which are useful to geologists
because they can be used for correlation. This is because they changed their form
over geological time in a specific way, so geologists use them to suggest the age of
the rocks in which they are found.
In class we will draw diagrams to show how these changes occurred. FOS 1 p 121
has similar diagrams that you can use for reference.
Features to learn are:
stipe, theca (plural is thecae), Didymograptus, Monograptus
Now make a list of the changes which occurred in the morphology of graptolites
during the Lower Palaeozoic era.
TASK 7 TRILOBITES
There is a trilobite on the front cover of this study guide. Label it fully using the
features you need to know:
glabella, cephalon, thorax, pygidium, genal spines, compound eyes, segments
TASK 8 PLANTS
Plants in the past have had a similar morphology to plants at present although they
are different species. Draw the diagram from FOS 1 p 136 to give you some idea
of how different plants looked. Label the roots, stem, branches and leaves.
TASK 9 REVISE MORPHOLOGICAL TERMINOLOGY
Prepare for a test on the morphological features of the fossil groups we have
studied.
Date of test…………………………………..
Use this box for notes
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GEOLOGY STUDY GUIDE
Module exam GL1 June 2005
ACTIVITY 2 : FOSSIL PRESERVATION
Margin notes
TASK 10 PRESERVATION OF FOSSILS
Watch the preservation powerpoint FOS 6 and make notes on the methods of
preservation they show. Use FOS 7 to learn more detail by highlighting and
making review notes on each method of preservation. Use any method of review
notes that you are comfortable with.
TASK 11 MOULDS AND CASTS
Use FOS 8 to explain the complexities of internal and external moulds and casts.
You can practise your knowledge in the next task.
TASK 12 PRESERVATION PRACTICAL
Use the tray of specimens which show different methods of preservation. Look at
most of the fossils and write a comment about how you think each has been
preserved in rocks.
TASK 13 LIFE AND DEATH ASSEMBLAGES
We often want to know about whether an organism has been fossilised where it
lived (in situ) or whether it has been moved after death to a different environment.
Watch the powerpoint FOS 9 of life and death assemblages.
Make notes which explain the ideas and give you some examples.
TASK 14 DERIVED FOSSILS
Derived fossils are those which have been weathered out from the rock in which
they were originally deposited and then transported and deposited in more recent
sediments. They are therefore older than the rock in which they are found. Record
some examples of derived fossils from the class discussion.
TASK 15 EXAM QUESTION PACK
Complete the Fossils EQP
Deadline: ……………………………………
TASK 16
REVIEW NOTES
If you want to do any more reading because you are interested in fossils look in the
library under section 550. FOS 11-15 are examples of books which will give you
more information and often contain excellent photographs.
You need to learn this topic now.
Review notes deadline: …...........................................
Use this box for notes
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