Weathering Crossword

Heating and cooling that cause rocks to expand and contract. Temperature changes cause outer layers of rock to crack. -
When the outer layers of rocks crack and break off -
Liquid water seeps into cracks and expands when frozen, causing small cracks to widen and open up -
Animals scratch and dig on the surface breaking rocks. Plant roots break up soil, even asphalt and concrete -
Gravity can pull loosened rocks down hills or mountains in a landslide. When mixed with water it is a mudslide -
Wind carrying particles smooth rocks on the surface. Water carrying particles smooth rocks in rivers and oceans -
When minerals that hold rocks together are dissolved. -
Oxygen chemically combines with other elements such as iron making iron oxide or rust -
When carbon dioxide dissolves into water it is called carbonic acid. This can dissolve rocks but is too weak to harm people or plants. It can dissolve limestone and soft rocks. -
Sulfur dioxide is a product of burning fossil fuels and it combines with water to form acid rain, which affects marble statues, paint, and metal -
Lichens or mosses break down rocks and can form soil by producing weak acids. -