Zeolite facies describes the mineral assemblage resulting from the pressure and temperature conditions of low-grade metamorphism.
The zeolite facies is generally considered to be transitional between diagenetic processes which turn sediments into sedimentary rocks, and prehnite-pumpellyite facies, which is a hallmark of subseafloor alteration of the oceanic crust around mid-ocean ridge spreading centres. The zeolite and prehnite-pumpellyite facies are considered burial metamorphism as the processes of orogenic regional metamorphism are not required.
Zeolite facies is most often experienced by pelitic sediments; rocks rich in aluminium, silica, potassium and sodium, but generally low in iron, magnesium and calcium. Zeolite facies metamorphism usually results in the production of low temperature clay minerals into higher temperature polymorphs such as kaolinite and vermiculite.
Mineral assemblages include kaolinite and montmorillonite with laumontite, wairakite, prehnite, calcite and chlorite. Phengite and adularia occur in potassium rich rocks. Minerals in this series include zeolites, albite, and quartz.
This occurs by dehydration of the clays during compaction, and heating due to blanketing of the sediments by continued deposition of sediments above. Zeolite facies is considered to start with temperatures of approximately 50 - 150 °C and some burial is required, usually 1 - 5 km.
Zeolite facies tends to correlate in clay-rich sediments with the onset of a bedding plane foliation, parallel with the bedding of the rocks, caused by alignment of platy clay minerals in a horizontal orientation which reduces their free energy state.
Generally plutonic and volcanic rocks are not greatly affected by zeolite facies metamorphism, although vesicular basalts and the like will have their vesicles filled with zeolite minerals, forming amygdaloidal texture. Tuff can also become zeolitized, as is seen in the Obispo formation on the California coast.
Zeolitefacies describes the mineral assemblage resulting from the pressure and temperature conditions of low-grade metamorphism. The zeolitefacies is...
temperature and sillimanite is stable at high temperature. The zeolitefacies is the metamorphic facies with the lowest metamorphic grade. At lower temperature...
the zeolite, prehnite-pumpellyite, blueschist, and eclogite facies stability zones of subducted oceanic crust. Zeolite and prehnite-pumpellyite facies assemblages...
magmatic body (metasomatism) sometimes takes place. The hornfels facies is the metamorphic facies which occupies the lowest pressure portion of the metamorphic...
Granulites are a class of high-grade metamorphic rocks of the granulite facies that have experienced high-temperature and moderate-pressure metamorphism...
hardness of 3. It is a low-temperature hydrothermal phase occurring in zeolitefacies alteration of dolerites. Associated minerals include prehnite, scolecite...
used to trace the low grade metamorphic transition from zeolitefacies to greenschist facies (diagenetic zone to epizone). This change is flagged by the...
They are slightly deformed into very-low-grade metamorphic rocks in zeolitefacies. Through basin analysis, it is believed that the two terranes are a...
metabasalt of the zeolite and prehnite-pumpellyite facies, but as the basalt subducts to greater depths, it is metamorphosed to the blueschist facies and then...
example) the amphibolite facies of a marble will not be identical with the amphibolite facies of a pellite. However, the facies are defined such that metamorphic...
fragments mixed and milled by the eruption. Minerals in the marginal facies include zeolite minerals, micas, kaolinite and clays, typical of post-eruption hydrothermal...
the zeolite, prehnite-pumpellyite, blueschist, and eclogite facies stability zones of subducted oceanic crust. Zeolite and prehnite-pumpellyite facies assemblages...
the lateral and vertical facies changes that occur within the Denver Basin. The base of the D1 is marked by the abrupt facies change at the top of the...
sodium. Mitchell[1] has suggested that rocks belonging to the "lamprophyre facies" are characterized by the presence of phenocrysts of mica and/or amphibole...
dolomite (often to a scratched surface in a rock), for it to effervesce. Zeolite minerals will not effervesce in acid; instead, they become frosted after...
References External links facies The sum of the lithological and faunal characters of a sediment is its facies. Lithological facies involves composition,...
many minerals such as asbestos, Magnesite, perlite, mica, phosphates, zeolites, clay, pumice, quartz, and silica, as well as elements such as sulfur,...
being marked by the appearance of lapilli tuff cemented by calcite or zeolite, with abundant xenoliths and accidental lithics of felsic type and a size...
(December 1992). "Facies of sunken early cretaceous atoll reefs and their capping Late Albian drowning succession (Northwestern Pacific)". Facies. 27 (1): 153–174...
leaches alkali metals and calcium from the glass. New minerals, such as zeolites, clays, and calcite, crystallize from the dissolved substances and cement...
Parts of the formation are known to have experienced Prehnite-pumpellyite facies metamorphism. The Tinguiririca fauna is known from the fossils found in...
(December 1992). "Facies of sunken early cretaceous atoll reefs and their capping Late Albian drowning succession (Northwestern Pacific)". Facies. 27 (1): 153–174...
influence is observed in the main outcrop of the last unit, where enriched Zeolite by Barium is suggested to derive from oceanic water, that may have circulated...
(CaAl2Si3O10·3H2O), but it has Nickel-Strunz identifier 9.GA.05 (zeolites with T5O10 units – the fibrous zeolites); mogánite (SiO2), but it has Nickel-Strunz identifier...
material has formed calcite, chlorite, clay, iddingsite, montmorillonite, zeolite, and a mineral that could be celadonite. Volcanogenic sandstones and traces...
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