A large range of cliff types do not have profiles with constant slopes
but, as with other types of slopes such as hillsides, may be made up of
more than one slope unit. Bevelled cliffs (I) are common throughout
the world and simply reflect the fact that weathering is the main
group of processes at work on the upper slopes and give them a
rounded profile, whereas the dramatic processes of marine erosion
produce the much steeper lower slopes. Vegetation cover helps to
make the upper slope relatively stable. Where bevelled cliffs form in
softer rocks, such as clays and soft sandstones, the overall profile is
much smoother and rounded; this is often known as a hog's back cliff
(J). In tropical locations where the shore is formed of soluble rocks,
such as coralline limestone, solution leads to the formation of deep
notches at the foot of cliff faces and in some cases these notches
become caves. Such tropical cliffs (K) have distinctive breaks in slopes
and are well developed in many locations such as a Liliputa Beach on
Samar Island in the Philippines and on Efate Island in Vanuatu