Post on 27-Dec-2015
Sedimentary Rock• Definition: formed by weathering causing
sediments to build up in layers
• Usually found where there used to be a river, lake, ocean, sea, etc.
• p. 242
Notice the striping that goes across the rocks, that is formed by layers be set down in an ocean.
Fossil• Definition: records of past life on earth
• May be an imprint (mold), a bone, or the remains of something (cast)
• p. 244
Mold
• Definition: a hollow space in a rock with the shape of an animal or plant
• This is like when you make an imprint of your hand in clay or plaster
• Most often found in sedimentary rock
Cast
• Definition: hard sediments in the form of an animal or plant
• This is what happens when the animal or plant materials are replaced by minerals (all dinosaur bones)
Conglomerate
• Definition: sedimentary rocks made of small pebbles and dirt
• Think of pulling up a piece of concrete – with big stones and small pebbles and the tiny pieces that pull it all together
• Miss Veach has a good example, if you come ask nicely to see it – sorry, I couldn’t find a good picture.
Erosion• Definition: the process of soil being
washed away (by water)
• Related word: Weathering, the process of soil being blown away
• p. 264-266Erosion
Wea
ther
ing
Crystal
• Definition: a pattern of atoms repeated so many times it becomes large enough to be seen
Water crystals
Diamond crystal
Magma• Definition: hot liquid rock found in the core
of the earth
• You can’t see a picture of it because once it comes out of the earth (where we could take a picture) it is called lava!
Volcano• Definition: an opening in the Earth where
magma comes onto the Earth’s surface (crust)
• p. 270
Iceland
Metamorphic Rock• Definition: formed by heat and pressure
• Starts as Igneous or Sedimentary rock that is changed by heat and/or pressure
• p. 248
When granite is put under heat and pressure it becomes gneiss – the wavy part shows the pressure it was under.