1. A B C c b a c A B
H= a(sinB)
B = drill plunge
a =(cSinA/SinC)
A =Tan -1 {tan( dip bedding plane)*sin(strike difference)
h= (cSinA/SinC)*Sin(drill plunge) b a C

2. A B C

3. A B C
A= Tan -1 {tan( dip bedding plane)*sin(strike difference)} or derive on stereonet
B = Drill plunge
C = 180-(A+B)

4. A B C c b a c A B b a
c = distance along drill trend to plane exposure C

5. Law of Sines c A B h b a
c = distance along drill trend to plane exposure
a = (cSinA/SinC
b = (cSinb/SinC
h= a(sin B) C

6. A B C c b a c A B
H= a(sinB)
B = drill plunge
a =(cSinA/SinC)
A =Tan -1 {tan( dip bedding plane)*sin(strike difference)
h= (cSinA/SinC)*Sin(drill plunge) b a C

7. H =(cSinA/SinC)*Sin(drill plunge)
B = drill plunge
a == (cSinA/SinC)
A =Tan -1 {tan( dip bedding plane)*sin(strike difference)
c= horizontal distance
h = [{horizontal*sin(apparent dip)} / Sin {180-(drill plunge +apparent dip)}] * Sin (drill Plunge

8. A B C c b a c A B
Now we know (h)
= vertical depth b a C

9. Get the plunge of intersection line

10. h’ A x B a’ h w C
x = distance between drills
w = vertical change
h’= w + h
a’ = new drill depth
w =
h’ = [{horizontal*sin(apparent dip)} / Sin {180-(drill plunge +apparent dip)}] * Sin (drill Plunge)] + {x/cos(strike diff)}* tan (plunge intersection)}
a’ = h’/Sin (drill plunge)

12. A B C c b a c A B b a C
= a + drill distance * tan (angle between horizontal line on the drill plane and intersection line)

20. Consider Three drill holes
Orientation
Bedding to Core axis a
200/40 40 b
090/50 55 c
298/58 5

21. Calculating Core axis pole to bedding angle60
Core Axis 30
Bedding
Pole to Bedding
Drill hole
Orientation
Bedding to Core axis
Core axis to Pole a
200/40 40 50 b
090/50 55 35 c
298/58 5 85

22. Rotations 30

23. 3 1

24. Rotate to the Horizontal1 3

25. Possible bedding pole orientations – comparing hole 1 & 3

26. Now compare Hole 1 with Hole 2

28. Compare possibilities = pole to bedding of ~ 135 / 40

29. True Orientation of Bedding

30. N
20o
Hinge Trace
40o
60o A
70o B
20 Meters