How is a sedimentary rock formed?

How is a sedimentary rock formed?

• A. From melted rock that cools.
• B. From layers of sediments compacted and cemented together over time.
• C. From minerals crystallizing underground.
• D. From heat and pressure deep underground.

Answer: (B)

Sedimentary rocks form when loose sediments are pressed together and glued by minerals over time. Sediments come from weathering and erosion of existing rocks and can accumulate in layers in environments like rivers, lakes, or oceans. As more layers pile up, the weight compacts the lower layers, and minerals dissolved in water precipitate between the grains, cementing them into a solid rock. This process, called lithification, turns sand, silt, clay, or organic remains into rocks such as sandstone, shale, or limestone. Melted rock that cools becomes an igneous rock, not sedimentary. Minerals crystallizing underground describe igneous or vein processes, and heat and pressure deep underground produce metamorphic rocks.

Sedimentary rocks form when loose sediments are pressed together and glued by minerals over time. Sediments come from weathering and erosion of existing rocks and can accumulate in layers in environments like rivers, lakes, or oceans. As more layers pile up, the weight compacts the lower layers, and minerals dissolved in water precipitate between the grains, cementing them into a solid rock. This process, called lithification, turns sand, silt, clay, or organic remains into rocks such as sandstone, shale, or limestone.

Melted rock that cools becomes an igneous rock, not sedimentary. Minerals crystallizing underground describe igneous or vein processes, and heat and pressure deep underground produce metamorphic rocks.