Decayed organic material.
At its broadest, the term soil can refer to any kind of loose sediment. In geology, soil is the end result of rock weathering. And in soil science, it is weathered rock combined with decayed organic material that can support plant growth. How much of each is in the soil depends on the type of rock it weathered from, how long weathering has been occurring, the local climate (wet or dry, hot or cold), the abundance of plant life to decay into organics, and the ecosystem of living things that decomposes the dead plants. Sandstone is a sedimentary rock composed of sand-sized grains of mineral, rock or organic material. It also contains a cementing material that binds the sand grains together and may contain a matrix of silt-or clay-size particles that occupy the spaces between the sand grains. Sandstone is one of the most common types of sedimentary rock and is found in sedimentary basins throughout the world. It is often mined for use as a construction material or as a raw material used in manufacturing Mechanical weathering does the same thing to all rocks: breaks them down into small pieces, which eventually become the size of sand, silt, and clay. Sand, silt, and clay are primarily measures of grain size. Sand grains have a diameter from 1/16th to 2 mm. How much of each is in the soil depends on the type of rock it weathered from, how long weathering has been occurring, the local climate (wet or dry, hot or cold), the abundance of plant life to decay into organics, and the ecosystem of living things that decomposes the dead plants. The sand, silt, and clay that results from rock weathering form the basic components of soil. If the material stays where it formed-above or otherwise in contact with the unweathered parent rock-the soil is called a residual soil. How much of each is in the soil depends on the type of rock it weathered from, how long weathering has been occurring, the local climate (wet or dry, hot or cold), the abundance of plant life to decay into organics, and the ecosystem of living things that decomposes the dead plants. Sand is typically made mostly of varying amounts of material weathered from inland rocks (or seacliff material) and transported to the beach on the wind or in rivers, and/or shells and other hard parts precipitated out of the ocean water by marine organisms.  Many people think that soil is just dirt. To a scientist, soil is a loose mixture of small mineral fragments, organic material, water, and air that can support the growth of vegetation. The Source of Soil Because soils are made from weathered rock fragments, not all soils are the same. The kind of soil that forms depends on the source of the soil.  Shale is usually found in thin layers. The silt or clay that composes shale is made of very small pieces of weathered rock. The pieces are from 1/16 to 1/256 of a millimeter in diameter. The color of a sample of shale is that of the clay or silt that it was formed from. People that live in a desert region can easily find rocks on the surface. These rocks lay on a surface of clay that is also a product of weathering rock. Weathering is the process of breaking down rocks and minerals into smaller pieces by water, wind, and ice. Regolith is a layer of loose, heterogeneous superficial material covering solid rock. It includes dust, soil, broken rock, and other related materials and is present on Earth, the Moon, Mars, some asteroids, and other terrestrial planets and moons.  1 Clay is a sedimentary material made from bits of weathered rock that have combined with water. 2  Conglomerate rocks contain round river rocks surrounded by hardened sand or another type of sediment. 3  In swampy areas, plants die but they do not decay. 4  Instead, they turn into peat. 1 The White Cliffs of Dover in England are made from the shells and remains of trillions of tiny animals that died more than 65 million years ago. 2  Sandstones are rocks composed primarily of sand grains. The grains of sand in a sandstone are usually particles of mineral, rock or organic material that have been reduced to sand size by weathering and transported to their depositional site by the action of moving water, wind or ice. It also contains a cementing material that binds the sand grains together and may contain a matrix of silt-or clay-size particles that occupy the spaces between the sand grains. Sandstone is one of the most common types of sedimentary rock and is found in sedimentary basins throughout the world.
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what materials is made of weathered rock