2-7 Identifying Sedimentary Rocks Unit 2: Rocks and Minerals October 24, 2011 Sanders

Sedimentary Classification Clastic Rocks are sorted by grain size

Shale Shale is a rock whose particles are so small they cannot be seen to the unaided eye. The particles in shale are often carried far out to sea.

Siltstone Siltstone has particles that are almost invisible but has a gritty feel to them

Sandstone Sandstone is made of sand cemented together. The particles are visible and the texture is that of fine to course.

Conglomerate Conglomerate is a rock made from clearly visible particles such as pebble or even cobbles. Particles are rounded.

Breccia Breccia is like conglomerate in particle size but it has angular particles.

Chemical Rocks Sedimentary Rock is rock formed by the deposits of mineral and particles left behind by of water or, wind or glacial Ice.

Non Clastics

Rock Salt Evaporated remains of seawater. Notice it is not in a crystalline form of halite. It is monomineralic.

Rock Gypsum Rock gypsum, also an evaporate, has qualities of gypsum; soft, pink to white. Does not have the crystal shapes It is monomineralic

Dolostone Niagara Falls falls over dolostone. The soft rock falls out from underneath.

Limestone Is this rock made of minerals?

Coal Made from plants. Look to page 8 & 9 in the reference table and find the Carboniferous