What type of rock is formed from broken fragments cemented together?

What type of rock is formed from broken fragments cemented together?

• A. Igneous rocks
• B. Metamorphic rocks
• C. Clastic rocks
• D. Chemical rocks

Answer: (C)

Rocks are classified by how they form. Clastic sedimentary rocks are created when pieces of preexisting rocks—gradually broken down by weathering and erosion—are transported, deposited, buried, and then lithified. The fragments are held together by minerals that precipitate from pore water, acting like a natural cement. That process makes a rock out of broken fragments cemented into one solid mass. Sandstone, shale, conglomerate, and breccia are common examples of this type. Igneous rocks come from cooling and solidification of molten material, not from cemented fragments. Metamorphic rocks form when existing rocks are altered by heat and pressure, changing minerals and structure. Chemical rocks form by precipitation from solution rather than by cementing broken pieces together. So the description of rocks formed from broken fragments cemented together fits the clastic category precisely.

Rocks are classified by how they form. Clastic sedimentary rocks are created when pieces of preexisting rocks—gradually broken down by weathering and erosion—are transported, deposited, buried, and then lithified. The fragments are held together by minerals that precipitate from pore water, acting like a natural cement. That process makes a rock out of broken fragments cemented into one solid mass. Sandstone, shale, conglomerate, and breccia are common examples of this type.

Igneous rocks come from cooling and solidification of molten material, not from cemented fragments. Metamorphic rocks form when existing rocks are altered by heat and pressure, changing minerals and structure. Chemical rocks form by precipitation from solution rather than by cementing broken pieces together. So the description of rocks formed from broken fragments cemented together fits the clastic category precisely.