Meridianiite
Encyclopedia
Meridianiite — MgSO4•11H2O — is the crystalline 11-hydrate magnesium sulfate
phase that precipitates from solutions saturated in Mg2+ and SO42- ions at temperatures ≥ 2 ˚C. Clear to colorless, it is a naturally occurring mineral
species found on Earth
in a variety of environments including sea ice, crusts and efflorescence’s in coal/metal mines, cave systems, oxidized zones of sulfide deposits, salt lakes/playa’s and Antarctic ice-cores. Named for locality data obtained by the NASA Opportunity Rover
at Meridiani Planum
, it has been suggested that mineral casts present in the Martian sulfate deposits are indicative of this minerals former presence in the area. It is commonly associated with other evaporite
minerals such as epsomite
, mirabilite
, halide
s, and other sodium-magnesium-sulfates.
, having cell parameters a = 6.7459 Å, b = 6.8173 Å, c = 17.299 Å, a density
= 1.512 g/cm-3, x-ray diffraction peaks at d-spacing’s = 5.73, 5.62, 5.41, 4.91, 4.85, 2.988, 2.958 (highest intensity), and 2.940, and is IR active. It produces needle-shaped to broad flat crystals that are clear to colorless-white, and decomposes incongruently above 2 °C to produce epsomite
(MgSO4•7H2O) and water
.
as it transformed to anhydrous MgSO4. The crystal structure was later resolved by Peterson and Wang in 2006, revealing it belonged to the triclinic crystal system, and possessed 11 waters of hydration
, not 12. Meridianiite was officially named and approved as a new mineral species by the Commission on New Mineral Names and Mineral Nomenclature of the International Mineralogical Association in November of 2007.
is that geological processes on other planet
s or moon
s operate in much the same manner as they do on Earth
, at least for planetary bodies of similar size and composition. This has been the cornerstone of comparative planetary exploration, and has been the primary method of data interpretation for the current exploration of Mars
.
Imagery of the surrounding massive sulfate deposits sent back by the NASA
Opportunity Rover
in Meridiani Planum
, has indicated the existence of pervasive needle-shaped void spaces throughout the deposit. The now empty angular holes are interpreted as being cavities once filled by a highly soluble mineral species, most likely a magnesium sulfate
. These cavities are observed to closely match the crystal habit of Meridianiite, and have been proposed as sites where crystals of Meridianiite were located, having subsequently dissolved when environmental conditions rendered the crystal unstable. Due to the decomposition of Meridianiite to 70% epsomite
and 30% water
, is has been proposed that meridianiite may represent a periodic reservoir of water near the Martian surface. During warmer periods in Mars’ history it is possible that triggered melting of this mineral may help explain the occurrence of some of the chaotic, and short lived, surface-water episodes throughout Martian history.
Remote sensing
of other planetary bodies has also indicated the presence of numerous hydrated mineral species, including sulfates, near various planetary surfaces, a prominent example of which is Jupiter
’s moon Europa
. The relatively smooth, and very young surface of Europa
has been interpreted as evidence for a putative ocean beneath the moons icy surface, and is therefore suggestive of liquid brine at depth. Due to the cryospheric conditions present on Europa it is likely that any magnesium sulfate minerals present, and in contact with liquid water, would inherently occur as meridianiite, and thus, it may make up an important mineral phase, and liquid water reservoir at depth.
Magnesium sulfate
Magnesium sulfate is a chemical compound containing magnesium, sulfur and oxygen, with the formula MgSO4. It is often encountered as the heptahydrate epsomite , commonly called Epsom salt, from the town of Epsom in Surrey, England, where the salt was distilled from the springs that arise where the...
phase that precipitates from solutions saturated in Mg2+ and SO42- ions at temperatures ≥ 2 ˚C. Clear to colorless, it is a naturally occurring mineral
Mineral
A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...
species found on Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
in a variety of environments including sea ice, crusts and efflorescence’s in coal/metal mines, cave systems, oxidized zones of sulfide deposits, salt lakes/playa’s and Antarctic ice-cores. Named for locality data obtained by the NASA Opportunity Rover
Opportunity rover
Opportunity, MER-B , is a robotic rover on the planet Mars, active since 2004. It is the remaining rover in NASA's ongoing Mars Exploration Rover Mission...
at Meridiani Planum
Meridiani Planum
Meridiani Planum is a plain located 2 degrees south of Mars' equator , in the westernmost portion of Terra Meridiani. It hosts a rare occurrence of gray crystalline hematite...
, it has been suggested that mineral casts present in the Martian sulfate deposits are indicative of this minerals former presence in the area. It is commonly associated with other evaporite
Evaporite
Evaporite is a name for a water-soluble mineral sediment that result from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporate deposits, marine which can also be described as ocean deposits, and non-marine which are found in standing bodies of...
minerals such as epsomite
Epsomite
Epsomite is a hydrous magnesium sulfate mineral with formula MgSO4·7H2O or simply MgSO4. Epsomite forms as encrustations or efflorescences on limestone cavern walls and mine timbers and walls, as a volcanic fumaroles, and as rare beds in evaporate layers...
, mirabilite
Mirabilite
Mirabilite, also known as Glauber's salt, is a hydrous sodium sulfate mineral with the chemical formula Na2SO4·10H2O. It is a vitreous, colorless to white monoclinic mineral which forms as an evaporite from sodium sulfate bearing brines. It is found around saline springs and along saline playa lakes...
, halide
Halide
A halide is a binary compound, of which one part is a halogen atom and the other part is an element or radical that is less electronegative than the halogen, to make a fluoride, chloride, bromide, iodide, or astatide compound. Many salts are halides...
s, and other sodium-magnesium-sulfates.
Properties
Meridianiite belongs to the triclinic crystal systemCrystal system
In crystallography, the terms crystal system, crystal family, and lattice system each refer to one of several classes of space groups, lattices, point groups, or crystals...
, having cell parameters a = 6.7459 Å, b = 6.8173 Å, c = 17.299 Å, a density
Density
The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is ρ . In some cases , density is also defined as its weight per unit volume; although, this quantity is more properly called specific weight...
= 1.512 g/cm-3, x-ray diffraction peaks at d-spacing’s = 5.73, 5.62, 5.41, 4.91, 4.85, 2.988, 2.958 (highest intensity), and 2.940, and is IR active. It produces needle-shaped to broad flat crystals that are clear to colorless-white, and decomposes incongruently above 2 °C to produce epsomite
Epsomite
Epsomite is a hydrous magnesium sulfate mineral with formula MgSO4·7H2O or simply MgSO4. Epsomite forms as encrustations or efflorescences on limestone cavern walls and mine timbers and walls, as a volcanic fumaroles, and as rare beds in evaporate layers...
(MgSO4•7H2O) and water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
.
Discovery
Originally described in 1837 by C.J. Fritzsche as being a 12-hydrate member of the Mg-sulfate salts, it was known at the time as Frizsche’s Salt and not formally given a mineral name or designation. Its chemical formula was initially determined by calculating the weight loss from the crystal structure during dehydrationDehydration
In physiology and medicine, dehydration is defined as the excessive loss of body fluid. It is literally the removal of water from an object; however, in physiological terms, it entails a deficiency of fluid within an organism...
as it transformed to anhydrous MgSO4. The crystal structure was later resolved by Peterson and Wang in 2006, revealing it belonged to the triclinic crystal system, and possessed 11 waters of hydration
Mineral hydration
Mineral hydration is an inorganic chemical reaction where water is added to the crystal structure of a mineral, usually creating a new mineral, usually called a hydrate....
, not 12. Meridianiite was officially named and approved as a new mineral species by the Commission on New Mineral Names and Mineral Nomenclature of the International Mineralogical Association in November of 2007.
Planetary mineralogy
The fundamental principle of comparative planetary geologyGeology
Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...
is that geological processes on other planet
Planet
A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...
s or moon
Moon
The Moon is Earth's only known natural satellite,There are a number of near-Earth asteroids including 3753 Cruithne that are co-orbital with Earth: their orbits bring them close to Earth for periods of time but then alter in the long term . These are quasi-satellites and not true moons. For more...
s operate in much the same manner as they do on Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
, at least for planetary bodies of similar size and composition. This has been the cornerstone of comparative planetary exploration, and has been the primary method of data interpretation for the current exploration of Mars
Mars
Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...
.
Imagery of the surrounding massive sulfate deposits sent back by the NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
Opportunity Rover
Opportunity rover
Opportunity, MER-B , is a robotic rover on the planet Mars, active since 2004. It is the remaining rover in NASA's ongoing Mars Exploration Rover Mission...
in Meridiani Planum
Meridiani Planum
Meridiani Planum is a plain located 2 degrees south of Mars' equator , in the westernmost portion of Terra Meridiani. It hosts a rare occurrence of gray crystalline hematite...
, has indicated the existence of pervasive needle-shaped void spaces throughout the deposit. The now empty angular holes are interpreted as being cavities once filled by a highly soluble mineral species, most likely a magnesium sulfate
Magnesium sulfate
Magnesium sulfate is a chemical compound containing magnesium, sulfur and oxygen, with the formula MgSO4. It is often encountered as the heptahydrate epsomite , commonly called Epsom salt, from the town of Epsom in Surrey, England, where the salt was distilled from the springs that arise where the...
. These cavities are observed to closely match the crystal habit of Meridianiite, and have been proposed as sites where crystals of Meridianiite were located, having subsequently dissolved when environmental conditions rendered the crystal unstable. Due to the decomposition of Meridianiite to 70% epsomite
Epsomite
Epsomite is a hydrous magnesium sulfate mineral with formula MgSO4·7H2O or simply MgSO4. Epsomite forms as encrustations or efflorescences on limestone cavern walls and mine timbers and walls, as a volcanic fumaroles, and as rare beds in evaporate layers...
and 30% water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
, is has been proposed that meridianiite may represent a periodic reservoir of water near the Martian surface. During warmer periods in Mars’ history it is possible that triggered melting of this mineral may help explain the occurrence of some of the chaotic, and short lived, surface-water episodes throughout Martian history.
Remote sensing
Remote sensing
Remote sensing is the acquisition of information about an object or phenomenon, without making physical contact with the object. In modern usage, the term generally refers to the use of aerial sensor technologies to detect and classify objects on Earth by means of propagated signals Remote sensing...
of other planetary bodies has also indicated the presence of numerous hydrated mineral species, including sulfates, near various planetary surfaces, a prominent example of which is Jupiter
Jupiter
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...
’s moon Europa
Europa (moon)
Europa Slightly smaller than Earth's Moon, Europa is primarily made of silicate rock and probably has an iron core. It has a tenuous atmosphere composed primarily of oxygen. Its surface is composed of ice and is one of the smoothest in the Solar System. This surface is striated by cracks and...
. The relatively smooth, and very young surface of Europa
Europa (moon)
Europa Slightly smaller than Earth's Moon, Europa is primarily made of silicate rock and probably has an iron core. It has a tenuous atmosphere composed primarily of oxygen. Its surface is composed of ice and is one of the smoothest in the Solar System. This surface is striated by cracks and...
has been interpreted as evidence for a putative ocean beneath the moons icy surface, and is therefore suggestive of liquid brine at depth. Due to the cryospheric conditions present on Europa it is likely that any magnesium sulfate minerals present, and in contact with liquid water, would inherently occur as meridianiite, and thus, it may make up an important mineral phase, and liquid water reservoir at depth.