Sedimentary rock is one of the three main rock groups (along with igneous and metamorphic rocks) and is formed in four main ways: by the deposition of the weathered remains of other rocks (known as 'clastic' sedimentary rocks); by the accumulation and the consolidation of sediments; by the deposition of the results of biogenic activity; and by precipitation from solution.
Sedimentary rocks include common types such as chalk, limestone, sandstone, clay, and shale.
Sedimentary rocks cover 75% of the Earth's surface.
