how caves are formed
caves are underground passages that go
deep inside the earth. caves are created
through a combination of chemicals water
and pressure. the majority of caves are
found in limestone areas. limestone is a
very soft rock so water can easily shape or carves out a caves.
when it rains, water enters the soil and mixes with it.
when the water comes through the soil, the oxygen (or carbon dioxide) creates an
acid called carbonic acid, helping to dissolve the limestone. but sometimes,
water only drips a little bit, trickling bit by bit.this geologic process gradually
eats away at the limestone and carves an underground hole. over time,
the hole becomes larger and larger. over many thousands or years, the caves
gradually gets bigger. eventually it becomes big enough to walk inside and explore.
water and gas in caves
additionally, underground rivers find their way into caves through entrance holes.
make the caves bigger through erosion. when an underground river exits a caves,
it is called a spring. apart from the limestone caves, some caves are formed by a hydrogen gas.
it comes from deep below the earth and rises to the surface.
the gas dissolve or eats away at the rock and creates a caves.
other caves are sea caves. they are found along coastlines.
the waves pound the coastlines, eroding weak areas in the rock.