A fall line (or fall zone) is the geomorphologic break that demarcates the border between an upland region of relatively hard crystalline basement rock and a coastal plain of softer sedimentary rock.
A fall line (or fall zone) is the geomorphologic break. This geomorphologic break demarcates the border between an upland region of relatively hard crystalline basement rock. This geomorphologic break demarcates the border between a coastal plain of softer sedimentary rock.