Sedimentary Rock Process II
Written for the KidsKnowIt Network by: Brandon Guymon
Sedimentary rocks are formed from the broken down pieces of other rocks or debris cemented together by intense pressure and minerals deposited by water.There are many kinds of sedimentary rocks. Scientists divide the types of sedimentary rocks into four kinds. These are: clastic, biochemical, chemical, and other. We will talk about each kind.
So how does rock become broken down in the first place to form the sediments that make up sedimentary rocks? Overtime water, wind, heat, and ice wear the rock down causing it to fall apart.This process is called weathering and erosion. The weathered bits of rock are carried by what geologists call agents.Agents are streams, rivers, wind, glaciers, or really anything else that carries the bits of weathered rock away from the large rock that formed them.The most common agent is water in the form of streams or rivers.The weathered bits of rock are carried by the agent until the agent can’t move them anymore.The weathered bits of rock pile up into a big pile. The weathered rocks are called sediments. The pile is called a sediment bed.Sediments are usually classified by size:Gravel is the biggest, sand is the next smallest, followed by mud,and silt is the smallest.
Water is the most common agent to move rocks from one place to another.