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Sediment is a solid material that is transported to a new location where it is deposited. [1] It occurs naturally and, through the processes of weathering and erosion, is broken down and subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles.
Provenance is the reconstruction of the origin of sediments. All rock exposed at Earth's surface is subjected to physical or chemical weathering and broken down into finer grained sediment. All three types of rocks (igneous, sedimentary and metamorphic rocks) can be the source of sedimentary detritus. The purpose of sedimentary provenance ...
The aim of sedimentology, studying sediments, is to derive information on the depositional conditions which acted to deposit the rock unit, and the relation of the individual rock units in a basin into a coherent understanding of the evolution of the sedimentary sequences and basins, and thus, the Earth's geological history as a whole.
Figure 1 illustrates this relationship between sediment grain size and the depth of the marine environment. Figure 1. Illustrating the sediment size distribution over a shoreline profile, where finer sediments are transported away from high energy environments and settle out of suspension, or deposit in calmer environments.
Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary rocks are formed by diagenesis and lithification of sediments, which in turn are formed by the weathering, transport, and deposition of existing rocks. Metamorphic rocks are formed when existing rocks are subjected to ...
Eventually the sediments will become so dense that they would essentially form a rock. This process is known as lithification. Igneous rocks have crystallised from a melt or magma. The melt is made up of various components of pre-existing rocks which have been subjected to melting either at subduction zones or within the Earth's mantle.
In geology, sedimentation is the deposition of sediments which results in the formation of sedimentary rock. The term is broadly applied to the entire range of processes that result in the formation of sedimentary rock, from initial erosion through sediment transport and settling to the lithification of the sediments. However, the strict ...
Unlike Proterozoic rocks, Archean rocks are distinguished by the presence of heavily metamorphosed deep-water sediments, such as graywackes, mudstones, volcanic sediments and banded iron formations. Greenstone belts are typical Archean formations, consisting of alternating high- and low-grade metamorphic rocks.