FREE ASBOG Structural Geology Questions and Answers

Question 1

the orientation of the line-containing vertical plane.

Accepted Answer

Trend

Answer

The trend of a line is the bearing of a vertical plane that contains the line, measured in the direction of plunge. It describes the horizontal direction of the line's projection onto a horizontal plane. This geological measurement helps define the orientation of linear features such as fold axes or slickensides.

Question 2

the angle of an object measured in a direction other than parallel to the strike

Accepted Answer

Apparent Dip

Answer

Apparent dip is the angle that a planar geological feature, like a bedding plane or fault, appears to make with the horizontal when measured in any direction other than perpendicular to the strike. It is always less than or equal to the true dip. This measurement is useful when the true dip cannot be directly observed or measured.

Question 3

the slope's slope angle from the horizontal

Accepted Answer

Slope Angle (σ)

Answer

The slope angle (σ) refers to the angle of inclination of a slope or surface measured from the horizontal plane. It quantifies the steepness of a topographic feature or a geological surface. This angle is a fundamental measurement in geomorphology and geotechnical engineering.

Question 4

the horizontal angle between a given coordinate direction (usually north or south) and a certain time

Accepted Answer

Bearing

Answer

Bearing is the horizontal angle measured from a given coordinate direction, typically North or South, to a specific line or point. It specifies the direction of a line in a horizontal plane. This measurement is crucial in surveying and geological mapping for defining orientations.

Question 5

A horizontal line's bearing on an inclined plane

Accepted Answer

Strike

Answer

Strike is defined as the bearing of a horizontal line contained within an inclined plane. It represents the compass direction of the intersection of a geological surface with a horizontal plane. This measurement, along with dip, is fundamental for describing the orientation of planar geological features like bedding or faults.

ASBOG - Association of State Boards of Geology Practice Test

ASBOG - Association of State Boards of Geology Practice Test

FREE ASBOG Structural Geology Questions and Answers