Geology Reference
In-Depth Information
Fig. 4.17.
Thickness parameters for a
bed and topographic surface
dipping in the same general
direction
Fig. 4.18.
Thickness parameters for a
bed and topographic surface
dipping in opposite general
directions
If the dip of bedding is less than the dip of the topography, the second term in Eq. 4.21
(D2.24) is larger than the first, giving the correct, but negative, thickness. Taking the
absolute value corrects this problem.
The thickness of a unit which dips opposite to the slope of topography (Fig. 4.18) is
t
= eg + eh ,
(4.22)
where
eh = ea sin
δ
.
(4.23)
Substituting Eqs. 4.20a, 4.20c, and 4.23 into 4.22:
t
=
h
cos
sin
+
v
cos
.
(4.24)
α
δ
δ
