Geology
Sited below the village of Blackgang at the western end of the Undercliff, Blackgang Chine was, historically, a spectacular ravine (in 1800 a "steep gaunt ravine" descending 500 feet over about three-quarters of a mile).
The location is based on unstable terrain owing to the underlying Gault Clay strata, resulting in a succession of huge landslips giving the area a very rugged appearance akin to the better known Jurassic Coast. Currently the cliffs are eroding at a rate of about 3.5 metres per year, although this process is not gradual. Large areas of land tend to collapse in stages after periods of heavy rain. The areas most recent and destructive cliff falls occurred in 1928, 1961 and 1994. Continuing landslides and coastal erosion swept away the paths in the early 1900s, and have since obliterated the chine itself and repeatedly forced the park owners to move the clifftop facilities inland.
Read more about this topic: Blackgang Chine