Structural Geology Flashcards
Structure vocab
Accuracy
How close a measurement conforms with a standard or accepted value.
Apparent dip (a)
The inclination of a plane measured in a direction not pependicular to strike.
Apparent dip direction
The bearing of a vertical plane containing the apparent dip angle.
Attitude
The orientation in space.
β
The angle between strike and the apparent dip direction.
Bearing
The horizontal angle between a line and a specified coordinate direction, usually north or south.
depth (d)
The vertical distance from the ground surface downward to a feature of interest.
Dip (σ)
The inclination of the line of greatest slope of an inclined plane, measured perpendicular to strike.
Directed line
A lone described by its bearing and plunge.
Fold line
A hinge line along which a vertical cross section may be constructed and then flattened out to a horizontal or map view.
Inclination
General term for the vertical angle between the horizontal and a plane or line, measured downward.
Outcrop width (w)
The width of an outcrop, as measured on a map view, perpendicular to strike.
Pole
A line perpendicular to a plane, and represented as a point on a stereographic projection.
Plunge
The vertical angle between a line and horizontal
Projection
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)
The angle measured on a specific plane , between a line and the horizontal.
Slope angle (o)
The angle from the horizontal down to the slope.
Strike
The bearing of a horizontal lines on an inclined plane
Thickness (t)
The perpendicular distance between the top and bottom of a geologic unit.
Trend
The bearing of the vertical plane containing a line.
