What is it called when faults move gradually rather than suddenly?

Answer 1

• Faults are breaks in the crust where the crust has moved. The types of dip-slip faults are normal and reverse faults. In both of these, the movement is along the slope of the fault. Sudden movements along these faults can produce fault scarps. Layers of rock being misaligned is evidence of fault movement. Fault creep is caused by slow movement along the fault.
• In a normal fault, the plates are moving away from each other. This is due to tension. When the fault moves, the footwall rises relative to the hanging wall. Normal faults occur at divergent boundaries, such as ocean ridges. Normal faults can produce fault-block mountains.
• In a reverse fault, the plates are moving towards each other. This is due to compression. Here, the footwall falls relative to the hanging wall. A thrust fault is a special type of reverse fault, where the angle is shallow. Reverse faults occur at convergent boundaries, like subduction zones.
• A strike-slip fault is where the two plates move horizontally past each other. The force between them is called shearing. This type of fault is often called a transform fault, because they occur at transform boundaries.