Text: PROBLEM 2.8
Procedure:
1. Draw the first structural contour (Hint: through Margam Park No. 2)
2. Plot the second structural contour 100 m above the first (Hint: through Margam Park No. 1)
3. Use this spacing to plot two more structural contours at a 100 m contour interval
4. Divide that spacing by four and plot the rest of the contour lines (straight, parallel, equally spaced)
5. Measure the strike
6. Determine the dip direction
7. Calculate the dip angle
Draw the structural contours West Glamorgan for three boreholes drilled in Margam Park for the Field Vein, assuming the Two-Feet-Nine coal seam was encountered at the following elevations above sea level:
- Margam Park No. 1: -175 + 625 = 450 m
- Margam Park No. 2: -275 + 625 = 350 m
- Margam Park No. 3: -475 + 625 = 150 m (625 added to get Field Vein elev.)
Questions (type your answers below questions)
A) Give the strike and dip in quadrant notation
A)
B) Give the dip direction (azimuth) and dip angle
B)
C) Assuming True North is parallel to grid north. Express the declination in decimal degrees:
C)
D) Calculate the verbal scale (Hint: It will be an even number):
D)
E) Calculate the ratio scale (Hint: 39.370 in/m):
E)
F) Determine the elevation of the base of the Lower Greensand below the Cathedral at St Edmunds (within 1 m).
F)
Margam Park No. 450
G) Plot the field trace of the field vein to the east of Margam Park 3. Find where the structural contours cross the topo lines of the same elevation and connect those points. Extrapolate the field trace to the east boundary of the map.
500 m