What does evaporite mean?
An evaporite is a mineral or rock that forms when bodies of saline water evaporate, leaving behind the salts that were dissolved in them. Common evaporite minerals include halite (rock salt), gypsum, and anhydrite, all of which precipitate as water concentrates in restricted, arid basins such as desert lakes or partially cut-off seas. In geological usage the word covers both individual crystals and entire rock layers built up over thousands of years of alternating inflow and drying. Evaporites matter far beyond the classroom: they record past climates, can store hydrogen or nuclear waste because of their impermeability, and their tendency to flow under pressure creates salt domes that trap some of the world's largest oil and gas reserves. The term belongs mainly to geology and petroleum science, appearing most often in phrases like 'evaporite deposits' or 'evaporite sequence'.
nounA mineral or rock formed by the precipitation of dissolved salts from evaporating water, typically in arid basins; examples include gypsum, halite (rock salt), and anhydrite.
- A mineral deposit, such as gypsum or halite, precipitated directly from evaporating saline water.
- A body of rock composed largely of such minerals, formed in an enclosed basin under arid conditions.
"The thick evaporite deposits beneath the Gulf of Mexico include vast beds of halite laid down millions of years ago."
"Geologists identified layered evaporites in the core samples, evidence of repeated cycles of flooding and drying."
"Because evaporites deform plastically under pressure, they can form salt domes that trap oil and gas."
The plural is common when referring to multiple mineral beds or occurrences, and the word is frequently used as a mass/collective term for this class of deposits.
"Thick evaporites underlie much of the North Sea's southern gas fields."
Some of the world's most important oil traps exist because ancient seas evaporated and left behind thick salt beds — salt that later flowed like toothpaste and sealed petroleum underneath.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of evaporite
The word 'evaporite' derives from the verb 'evaporate', which comes from Latin 'evaporare', meaning to disperse in vapor, itself formed from 'ex-' ('out of') and 'vapor' ('steam, exhalation'). The suffix '-ite' is the standard ending for naming rocks and minerals. The term was coined in the nineteenth century by geologists studying chemically precipitated sediments.
Related word forms
How evaporite is actually used
Primarily a technical term used in geology, sedimentology, and petroleum exploration; rarely encountered in everyday speech. Often used attributively before nouns such as 'deposits', 'basin', or 'sequence'.
Easily confused with evaporite
'Evaporate' is a verb meaning to turn from liquid into vapor, while 'evaporite' is a noun for the solid mineral residue left behind by that process.