Understanding What Sedimentary Rock Is
Sedimentary rock is a type of rock formed from layers of sand, mud, minerals, or organic material that build up and harden over long periods of time.
How Sedimentary Rock Forms
Wind, water, and ice break down existing rocks into small particles. These particles settle in layers, and pressure from above compresses them into solid rock.
Common Types of Sedimentary Rock
Sandstone forms from compacted sand.
Shale forms from mud and clay.
Limestone often forms from shells and marine organisms.
Where Sedimentary Rocks Are Found
They are common in riverbeds, deserts, oceans, and lake bottoms—places where sediments naturally accumulate and build up over time.
Why Sedimentary Rocks Are Important
Sedimentary rocks often contain fossils, making them valuable for studying ancient plants, animals, and environments. They record Earth’s geological history.
How Sedimentary Rocks Change
With heat and pressure, sedimentary rock can transform into metamorphic rock. The cycle continues as Earth’s surface reshapes over millions of years.
The Simple Takeaway
Sedimentary rock forms from compressed layers of sediment. These rocks store fossils and reveal the history of Earth’s changing environments.