Consider how sedimentary rocks are formed from smaller particles called sediments. Sediments are composed of particles that often come from existing rocks. How are these particles produced?
weathering
decomposition
compaction
deposition
The particles that make up sediments are primarily produced through weathering. Weathering is the process by which rocks are physically or chemically broken down into smaller fragments. There are two primary types of weathering:
1. Mechanical Weathering: This occurs when rocks are physically broken down into smaller pieces without changing their chemical composition. It includes processes such as freeze-thaw cycles, where water filling cracks in rocks freezes and expands, causing the rocks to break apart. Other examples of mechanical weathering include abrasion from wind or water, and the actions of plant roots growing into cracks and splitting rocks.
2. Chemical Weathering: This occurs when rocks are broken down through chemical reactions that alter their composition. It involves processes such as oxidation, where oxygen reacts with minerals in the rock, causing them to break down. Other examples of chemical weathering include the dissolution of minerals by acidic rainwater, and the reaction of minerals with water to form new compounds.
Once rocks are weathered into smaller fragments, they can be transported by various agents such as water, wind, or ice. Eventually, these particles settle and are deposited in a new location, where they can accumulate and become compacted over time. Compaction occurs as the weight of overlying sediments squeezes the particles together, reducing the empty spaces between them. This compaction, along with the presence of natural cements, leads to the formation of sedimentary rocks over long periods of time.
pick one of the options given
The particles that make up sediments are primarily produced through weathering.
weathering
decomposition
compaction
deposition