What happened to this rock?
This boulder was split by gelifraction (water freezes and expands, working to wedge the rock open). This is a type of mechanical or physical weathering.
What happened to this sculpture?
Trees have slowly weathered stone by vines and roots expanding in and around rocks.
What caused these shapes?
Limestone was weathered by rainwater containing dissolved CO2 (this process is sometimes called carbonation and is a type of chemical weathering).
What is happening in this rock?
Even the tiniest bacteria, algae and lichens produce chemicals that help break down the rock on which they live. This is Biological Weathering.
How are sand dunes formed?
Sand dunes form when wind-blow sand starts to pile up.
What is the typical shape of a river valley?
They are typically V-shaped valleys.
What type of weathering is shown in the picture? a) Mechanical; b) Biological; c) Chemical; d) Magical
a) Mechanical (water soaks into small fissures and cracks, expands when it freezes in the winter, and physically breaks the rock apart)
What is eroding this land? a) Wind; b) Rain; c) Glaciers; d) Rivers.
b) Rain (Rain-splash erosion: rain splashing down on the land and dislodging weathered material such as pebbles or soil).
Was this valley eroded by a river ir by a glacier?
A U-shaped valley is an example of a glacial landform, carved by slowly moving glaciers.
Why are the hills protruding like that over the valley?
The hills are made of harder rocks than the softer rocks in the valley.
What type of weathering is shown in the picture? a) Mechanical; b) Biological; c) Chemical; d) Magical
b) Biological (plant roots can enter a small crack in a rock. As the root grows larger the crack gets larger. This weakens the structure of the rock).
What type of weathering is shown in the picture? a) Mechanical; b) Biological; c) Chemical; d) Magical
c) Chemical (Rocks that contain iron rust due to a process call oxidation).
What type of plate boundary is responsible for the formation of the Great Rift Valley?
Divergent (a horizontal extensional force stretches the lithosphere, and it becomes thinner. Eventually, it will rupture).
