What is it?
Weathering is when the shape of
a rock is changed
• Physical weathering is when a rock breaks into
smaller pieces. The change in the rock is physical
with no new substances formed. Atom structure
stays the same.
Ex - Frost action, abrasion, pressure release
• Chemical weathering is when a rock goes through a
chemical reaction with water and atmospheric gases
and decomposes. Atoms rearrange and new
substances form.
Ex - Rusting, acid breakdown, solution weathering
Rust
Acid rain
(solution weathering)
Plant Wedging
As this tree grows, you
can imagine how this
will affect the rock.
Some species even
release a chemical
from their roots that
helps decompose the
rock too.
Oxidation
Lichen
Ice Wedging
Abrasion
Salt Crystallization