A sinkhole is a depression that forms in the ground as the surface layer slowly or quickly collapses. Rainwater is naturally a weak acid. Most of the acid in the rainwater is carbonic acid which reacts with limestone and changes it into a new substance. The new substance
dissolves in the water which drains away. This leaves cracks and holes underneath the surface that can collapse. The formation of one
type of sinkhole is shown below.
topsoil
limestone
"hain
rain
pond
Rainwater dissolves some
limestones
and carries some
of the new solution away. This
forms cracks which results in
a small depression
The dissolving of the limestone
makes bigger cracks. The cracks
are fitted with topsoil and a pond
forms
3
Underneath a sinkhole, cracks can lead to other areas where the limestone has been dissolved. A much larger hole is formed by
the same processes of chemical weathering and erosion. What does this most likely form?
O A. a delta
B.
a lake
C.
a cave
D.
a coastline