Geology Reference
In-Depth Information
Fig. 6.16.
Dip-domain cross-section construction technique.
a
Map of dips measured along a stream
traverse and the boundaries (
dotted lines
) between interpreted dip domains.
b
Initial stage of cross-
section construction showing domain dips and hinge locations with axial surfaces that bisect the hinges.
X:
axial-surface intersection points.
c
Completed cross section. (After Gill 1953)
6.4.1.2
Cylindrical Fold Example
The steps in building a cross section and interpolating the geometry using the con-
stant bed thickness dip-domain method is illustrated with the Sequatchie anticline
(Fig. 6.17). The map is characterized by domains of approximately constant dip, mak-
ing it a good candidate for a dip-domain style cross section. The fold is nearly cylin-
drical within the map area and so the geometry of the structure should be constant
along the axis. The crestal line is horizontal (Fig. 5.8b), making a vertical section the most
appropriate. Prior to drawing the section, the stratigraphic thicknesses are determined
and summarized in a stratigraphic ruler at the same scale as the map (Fig. 6.18).
