Geoscience Reference
In-Depth Information
Find a good surface that is representative of
the overall dip of the plane to measure.
Determine the general direction of dip by
looking at the plane or you can pour fluid over
the bedding plane to see which way it runs.
In some cases it may be necessary to smooth
out the variations on the surface by placing a
notebook or clipboard on the bedding plane,
but take care to ensure that this is not
biased by a small irregularity. Hammer near
left hand side shows the plane chosen in
this case.
2
2. Set the clinometer mode
Prepare the compass-clinometer for the
clinometer mode by setting the top of the
clinometer part so that it is parallel to the
long edge of the compass-clinometer
(i.e. put the compass dial at 90-270°).
3. Dip magnitude
Place the long edge that is at the base of the
clinometer scale on the bedding plane,
with the long edge of the compass-clinometer
parallel to where you estimate the maximum
dip direction lies (i.e. pointing down the slope).
While looking at the clinometer reading,
carefully rotate the compass-clinometer device
slightly (as shown by the arrows) to find the
line of maximum dip.
Read off the maximum dip. In this case it is
12°. Note that the dip can be read from either
side of the Silva-type compass-clinometer.
Figure 2.6
How to use the Silva-type compass-clinometer to measure the orientation and dip of a plane using
the contact method. The parts of the compass-clinometer are shown in Figure 2.3d and e.
