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sea caves. When sea waves continuously strikes at the rocks, cracks develop and over

time they become caves like structure that are called sea caves.
(ii) Sea Arches : A sea arch is a natural arch or bridge made of stone that has been created
through the process of land, wind or water erosion.

(iii) Stacks : Further erosion by the ocean waves will finally lead to the total collapse of
the arch and breaks the roof. Then, seaward portion of the headland will remain as a
pillar, that is widely known as a stack.

Sea Caves Sea Arch Sea Arch

(iv) Sea Cliff : The sea water coast rising almost vertically above the sea water is called a
sea cliff.

(v) Sea beach : A beach is a
coastal land form formed
when the sea waves deposit
sediments along the sea
shore.

Work of icE Sea Cliff Sea Beach

Glaciers or rivers of ice, as they are called, originate from
snow field in the high mountain areas or ice caps in polar
regions. The erosion work of ice results in formation of ‘U’
shaped valleys which are deep and have steep sides. As the
ice melts, the hollows created by glaciers get filled with
water forming lakes in the mountainous region. The big

and small rock pieces, silt and sand gets deposited. These
deposits are called “glacial moraines”.
Sea Beach

Work of WiNd

Wind is also an important geomorphic agent of erosion. But, it is not as much affective as rivers
and sea waves. Wind is comparatively minor agent because of the low density of air as compared
to the rocks and water. Wind works as an active erosional agent in the desert areas.
(i) Mushroom rocks : Mushroom rocks also called Rock Pedestals are found in deserts. These

are formed when the winds erode the lower section of the rock more than the upper part
and the rocks take form of a mushroom with a narrower base and wider top.

Social Studies-7-7
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