The upper mantle above deep is broken into the " Northern Apennines Arc " and the " Calabrian Arc ", with compressional forces acting in different directions radially toward the arcs'centers of curvature.
12.
Between 102�E and the AAD, where the spreading rate is constant, the left-stepping transform faults suggest the presence of oblique extensional forces while the presence of a long, elevated ridge near the 96�E right-stepping transform suggests a compressional force is also active.
13.
Factors that make Arches National Park sensitive to visitor damage include : semiarid region, and the scarce, unpredictable rainfall, lack of deep freezing, and lack of plant litter which results in soils that have both a low resistance to, and slow recovery from, compressional forces such as foot traffic.
14.
Compressional forces have been acting from north to south in the Alps and from south to north in the Apennines, but instead of being squeezed into mountains the valley has been subsiding at 1 to per year since about 25 mya, before the Apennines It is now known to be not an erosional feature but is a filled portion of the Adriatic Trench, called the Adriatic foredeep after its function as a subduction zone was discovered.
