how to find fossils
How to find fossils
see also: What to do once
you find a fossil
Fossils are found
in sedimentary rocks most of the time. Sometimes fossils can be found
under
volcanic ash or even preserved under a lava flow, but this is very
rare.
NOTE: Sedimentary
rocks do not always have fossils in them.
Layers are a
characteristic of sedimentary rocks. The bottom layers are naturally
the
oldest.
Some types of rocks found in the layers:
Limestone,
mainly calcium carbonate, common in warm, shallow seas, often has
fossils.
Shale
is a fine grained rock formed from silt and clays. It preserves fossils
well.
Sandstone
is widespread in desert deposits and on shallow water sediments.
Ripple marks
and Mud cracks are characteristics of many sedimentary rocks formed
in shallow waters. Ripple marks are common in shale. Mud cracks are
form
when mud drys quickly. These imply the presence of sunlight, water and
moderate temperature conditions related to the possibilities of life.
WHERE TO LOOK
LOOKING IN
CREEK BEDS AND BANKS

1.Start at the
bottom of the creek
2.Look for fragments
of bone
3.Follow them
up the creek looking for larger, more angular bits as you go
4.When the bits
of bone stop. Look up on the banks for the fossils
5.Find the larger
piece of bone and excavate it
LOOKING AT INDEX FOSSILS
An index fossil is a fossil that is useful in working out the age of a bed of rock. You need several index fossils in combination to got a good date.
A good index fossil needs:
- To be easy to identify
- Common
- Exists over a short geological time range
- Has worldwide distribution
A simple example shown below

A more complex example shown below
