ASBOG-FG QUESTIONS AND ANSWERS
WITH VERIFIED SOLUTIONS 2024
Accuracy - ANSWER How close to a measurement conforms with a standard or accepted value.
Apparent dip (α) - ANSWER The inclination of a plane measured in a direction not perpendicular to
strike.
Apparent dip direction - ANSWER The bearing of the vertical plane containing the apparent dip angle.
Attitude - ANSWER The orientation in space.
β - ANSWER The angle between strike and the apparent dip direction.
Bearing - ANSWER The horizontal angle between a line and a specified coordinate direction, usually
north or south.
Dip (δ) - ANSWER The inclination of the line of greatest slope of an inclined plane, measured
perpendicular to strike.
Fold Line - ANSWER A hinge line along which a vertical cross section may be constructed and the
flattened out to a horizontal or map view.
Inclination - ANSWER A general term for the vertical angle between the horizontal and a plane or line
measured downward.
Outcrop Width (w) - ANSWER The width of an outcrop, as measured on a map view, perpendicular to
strike.
Pole - ANSWER A line perpendicular to a plane, and represented as a point on a stereographic projection.
, Plunge - ANSWER The vertical angle between a line and horizontal.
Precision - ANSWER The degree of agreement or consistency of repeated measurements
Projection - ANSWER The process by which points on one surface are transferred to another surface,
such that in each view (map or cross section) the points correspond.
Rake (Pitch) - ANSWER The angle measured in a specific plane, between a line and the horizontal.
Slope Angle (σ) - ANSWER The angle from the horizontal down to the slope.
Stereonet - ANSWER A representation of angular relationships between planes and lines. In structural
geology, a stereonet is synonymous with Wulff net, an equal angle stereographic projection.
Strike - ANSWER The bearing of a horizontal line in an inclined plane.
Thickness (t) - ANSWER The perpendicular distance between the top and bottom of a geologic unit.
Trend - ANSWER The bearing of the vertical plane containing a line.
Blind Thrust - ANSWER A thrust fault that dies out in the subsurface as it looses slip and stratigraphic
seperation
Detachment Fault - ANSWER A low-angle normal fault
Dip-Slip Fault - ANSWER A fault in which the movement is parallel to the dip of the fault plane, such as a
normal, reverse, or listric fault
Footwall block - ANSWER The block that underlies a non-vertical fault
WITH VERIFIED SOLUTIONS 2024
Accuracy - ANSWER How close to a measurement conforms with a standard or accepted value.
Apparent dip (α) - ANSWER The inclination of a plane measured in a direction not perpendicular to
strike.
Apparent dip direction - ANSWER The bearing of the vertical plane containing the apparent dip angle.
Attitude - ANSWER The orientation in space.
β - ANSWER The angle between strike and the apparent dip direction.
Bearing - ANSWER The horizontal angle between a line and a specified coordinate direction, usually
north or south.
Dip (δ) - ANSWER The inclination of the line of greatest slope of an inclined plane, measured
perpendicular to strike.
Fold Line - ANSWER A hinge line along which a vertical cross section may be constructed and the
flattened out to a horizontal or map view.
Inclination - ANSWER A general term for the vertical angle between the horizontal and a plane or line
measured downward.
Outcrop Width (w) - ANSWER The width of an outcrop, as measured on a map view, perpendicular to
strike.
Pole - ANSWER A line perpendicular to a plane, and represented as a point on a stereographic projection.
, Plunge - ANSWER The vertical angle between a line and horizontal.
Precision - ANSWER The degree of agreement or consistency of repeated measurements
Projection - ANSWER The process by which points on one surface are transferred to another surface,
such that in each view (map or cross section) the points correspond.
Rake (Pitch) - ANSWER The angle measured in a specific plane, between a line and the horizontal.
Slope Angle (σ) - ANSWER The angle from the horizontal down to the slope.
Stereonet - ANSWER A representation of angular relationships between planes and lines. In structural
geology, a stereonet is synonymous with Wulff net, an equal angle stereographic projection.
Strike - ANSWER The bearing of a horizontal line in an inclined plane.
Thickness (t) - ANSWER The perpendicular distance between the top and bottom of a geologic unit.
Trend - ANSWER The bearing of the vertical plane containing a line.
Blind Thrust - ANSWER A thrust fault that dies out in the subsurface as it looses slip and stratigraphic
seperation
Detachment Fault - ANSWER A low-angle normal fault
Dip-Slip Fault - ANSWER A fault in which the movement is parallel to the dip of the fault plane, such as a
normal, reverse, or listric fault
Footwall block - ANSWER The block that underlies a non-vertical fault
