Answer:
The first blank should be filled with "dip," and the second blank should be filled with "strike."
Step-by-step explanation:
The dip of a rock structure, such as a fault, refers to the angle the surface makes with the horizontal plane. It represents the inclination or tilt of the rock layers or fault plane relative to the horizontal. The dip is measured perpendicular to the strike, which is the direction of a horizontal line on an inclined surface.
On an inclined rock surface or fault plane, the strike is the direction of a horizontal line within that plane. It represents the intersection of the inclined surface or fault plane with a horizontal plane. The strike is expressed as a compass direction (e.g., north, south, east, west) or in degrees from north.
Understanding the dip and strike of rock structures is essential in geology, particularly in structural geology and geological mapping. These measurements help geologists interpret the orientation and geometry of rock layers, faults, folds, and other geological features. They provide important information about the deformation history, stress regimes, and structural characteristics of the Earth's crust in a particular area.