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When you gulp a glass of water, it’s hard to imagine the
liquid’s incredible power. It can slowly demolish rocks.
And it can carry the broken bits to brand-new places.
Rivers and streams can also wash away sand, silt, and
clay.All these sediments travel downstream to oceans
and lakes.
As time passes, the sediments build up—layer by
layer by layer. The weight of the materials on top
presses down on the lower layers. All that pressure
squeezes out the water. Then it cements the
sediments together to form
sedimentary rock
.
Sedimentary rock is the most common kind
of rock on Earth’s surface. If you look closely at
sandstone, limestone, or shale, you might be
able to see its layers.
Layer by
Layer
