5.2 sedimentary rocks
DESCRIPTION
TRANSCRIPT
Formation of Sedimentary Rock
Formation of Sedimentary Rock
• Made up of an accumulation of various types of sediment.
• Compaction or cementation are two process that form sedimentary rock.–Compaction- when all air and water is squeezed
out of sediment–Cementation- when minerals are left between
the fragments of sediment.
3 Types of Sedimentary Rocks
•Clastic Sedimentary Rock- rock is made up of rock fragments that have been moved by water, wind or ice.
•Chemical Sedimentary Rock- forms from minerals that precipitate from water.
•Organic Sedimentary Rock- forms from the remains of organisms.
Clastic Sedimentary rocks
• Rocks are classified by the sediments size.
•Conglomerates- rocks composed of rounded gravel size fragments or pebbles.–Individual pieces are easily seen.
• The sandstone group is made up of sand size grains that have been cemented together.
• The third group is shale, which consists of clay size particles the easily flake or break apart.
Conglomerates
Sandstone
Shale
Chemical Sedimentary Rocks
• Rocks that form from minerals that were once dissolved by water.
• These rocks are called evaporates.
Organic Sedimentary Rock
• Formed out of the remains of living things.
• Coal is a prime example of this.
Sedimentary Rock Features
• Easily identifiable–Layering–Ripples marks–Mud–Cracks–Fossils–Concretion