Geology Reference
In-Depth Information
1. Extend the dips at A and B so that they intersect at X.
2. On AX locate point Y such that YX = XB.
3. Bisect angle YXB. The bisector will intersect BC, the normal to B, at O
b
.
4. With center O
b
and radius BO
b
, draw the arc from B to Y. This arc is tangent to AY,
the straight-line extension of the dip from A.
The second method is to insert a dip such that the two data points are joined by two
circular arcs that are tangent at the data points and at the interpolated dip. The result
is a cross section with continuously curving beds. This method is given by Busk (1929)
and Higgins (1962). Beginning with the two dips A and B (Fig. 6.29):
1. Draw AA' perpendicular to the lesser dip at A; draw BB' perpendicular to the greater
dip at B.
2. Draw the chord AB. Angle CAB must be greater than angle CBA; if not, switch the
labels on points A and B.
3. Erect the perpendicular bisector of AB. This line intersects AA' at Z.
Fig. 6.29.
Interpolation using circular-
arc segments. (Modified from
Higgins 1962)
