Detritus (; adj. ''detrital'' ) is particles of
rock derived from pre-existing rock through
weathering
Weathering is the deterioration of rocks, soils and minerals as well as wood and artificial materials through contact with water, atmospheric gases, and biological organisms. Weathering occurs '' in situ'' (on site, with little or no movement ...
and
erosion
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is d ...
.
[Essentials of Geology, 3rd Ed, Stephen Marshak, p G-7] A fragment of detritus is called a
clast
Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus,Essentials of Geology, 3rd Ed, Stephen Marshak, p. G-3 chunks, and smaller grains of rock broken off other rocks ...
.
[Essentials of Geology, 3rd Ed, Stephen Marshak, p G-5] Detrital particles can consist of
lithic fragments (particles of recognisable rock), or of monomineralic fragments (mineral grains). These particles are often transported through
sedimentary
Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles ...
processes into depositional systems such as riverbeds, lakes or the ocean, forming sedimentary successions.
Diagenetic processes can transform these sediments into rock through
cementation and
lithification
Lithification (from the Ancient Greek word ''lithos'' meaning 'rock' and the Latin-derived suffix ''-ific'') is the process in which sediments compact under pressure, expel connate fluids, and gradually become solid rock. Essentially, lithificatio ...
, forming sedimentary rocks such as sandstone. These rocks can then in turn again be weathered and eroded to form a second generation of sediment. Detrital grains commonly weather at different rates, according to the
Goldich dissolution series The Goldich dissolution series is a method of predicting the relative stability or weathering rate of common igneous minerals on the Earth's surface, with minerals that form at higher temperatures and pressures less stable on the surface than minera ...
, which dictates that early crystallizing minerals are less stable at the earth's surface than late crystallizing minerals.
External links
Illinois State Geological Survey - Glossary of Geologic Terms
References
{{DEFAULTSORT:Detritus (Geology)
Sedimentology
eo:Gruzo (geologio)
he:דטריטי (גאולוגיה)
ja:砕屑物