Conglomerate rocks are formed by the sedimentary rock process, which is: erosion, transport, deposition and cementation. Two characteristic properties of conglomerate rock are that the sedimentary particles, or clasts, are greater than 2 millimeters in size, and the clasts are rounded in appearance. Sedimentary rocks with angular clasts are distinguished from conglomerates and are called breccias.Continue Reading
Conglomerates, like other sedimentary rocks, are formed from the detritus of source rocks, which results from weathering and erosion. As the pieces of source rock fall away, they are transported to other locations where they are deposited in layers. In the case of conglomerates, the transport by water causes the clasts to assume their rounded shape. As the sedimentary layers pile up in the stage of the formation process called deposition, pressure compacts the lower layers.
The final stage of the process is cementation. This refers to the development of new minerals between the layered and compacted sedimentary particles. These new mineral growths bind the particles together. The process is helped along by water entering through the pores in the sedimentary layers, and depositing minerals such as calcium carbonate or silica, between the particles. The water-borne precipitates act like cement and also decrease the porosity, or the degree of open space, between the sedimentary particles until new hardened rock is formed.Learn more about Geology
Sedimentary rocks form from the deposition and compression of inorganic and organic material on land or in water. Over 75 percent of the Earth's crust contains sedimentary rock.Full Answer >
Clay most commonly forms due to erosion or weathering; both methods involve rocks coming into contact with something, such as air or water, to form the clay from existing minerals on the ground. It is common for clay to form in specific geological environments, such as where there are volcanic deposits, marine sediments or soil horizons.Full Answer >
Sand is formed by the erosion of rocks, which become tiny particles. These tiny particles are picked up by wind and water and become sand.Full Answer >
Terrigenous sediments are marine sediments typically formed by the weathering and erosion of igneous and metamorphic rocks. Rivers are a major factor in the transportation of these sediments.Full Answer >