Question

How do clastic sedimentary rocks form?

Lava cools and hardens into rock.


Fragments of rock are squeezed and cemented together.


Solid chemicals in water harden and form rocks.


Plant and animal remains are squeezed and cemented together.

Answer 1

1. Clastic sedimentary rocks are made up of pieces (clasts) of pre-existing rocks. Pieces of rock are loosened by weathering, then transported to some basin or depression where sediment is trapped. If the sediment is buried deeply, it becomes compacted and cemented, forming sedimentary rock.
2. When lava reaches the surface of the Earth through volcanoes or through great fissures the rocks that are formed from the lava cooling and hardening are called extrusive igneous rocks. Some of the more common types of extrusive igneous rocks are lava rocks, cinders, pumice, obsidian , and volcanic ash and dust.
3. Sedimentary rocks are formed when sediments are deposited and then compacted and cemented together.
4. Sedimentary rocks are usually formed in water. these crystals grow large enough to fill the spaces they harden and form a solid rock.
5. Sedimentary Rocks. Biogenic Sedimentary Rocks. Biogenic sedimentary rocks are primarily composed of plant and animal remains, and include minerals created by organisms, such as corals, molluscs, diatoms or radiolarian which cover the ocean floor and later form limestones or cherts.