alkali feldspar


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Related to alkali feldspar: Plagioclase feldspar, quartz, hornblende, K feldspar

alkali feldspar

[′al·kə‚lī ′feld‚spar]
(mineralogy)
A feldspar composed of potassium feldspar and sodium feldspar, such as orthoclase, microcline, albite, and anorthoclase; all are considered alkali-rich.
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References in periodicals archive ?
The phenocrysts of plagioclase, hornblende, alkali feldspar and quartz are set in a felsophyric groundmass in a variable amount.
Investigation of gold and base metals mineralization and the petrochemical studies of the associated host rocks, Shagari Bala area, Skardu Gilgit- Baltistan, Pakistan
Quartz is low to moderate in abundance and feldspar is in significant proportion with plagioclase: alkali feldspar ratio high.
MODAL ANALYSIS OF SANDSTONE AND SILTSTONE LITHOFACIES FROM NORTHLAND ALLOCHTHON ROCKS, NEW ZEALAND
Alkali feldspars are represented by orthoclase and microcline.
The study of selected magmatic rocks thermic reworking for the purpose of thermic sinking
It consists mainly of perthitic alkali feldspar and quartz, and mafic minerals are less abundant than in the quartz alkali-feldspar syenite to alkali-feldspar syenite (Fig.
The Cape Porcupine Complex, northern mainland Nova Scotia--no longer a geological orphan
The degree of porosity depends on the composition of the parent feldspar grain, with plagioclase producing a dense clay matrix and alkali feldspar a highly porous clay matrix.
Relationships between fabric, water retention, and strength of hard subsoils in the south of Western Australia
It has a typical rapakivi texture with alkali feldspar megacrysts (ovoids) mantled by plagioclase.
Surface weathering of rapakivi granite outcrops--implications for natural stone exploration and quality evaluation/Rabakivi graniidi paljandite pindmise murenemise tahendus loodusliku kivi uuringutel ja kvaliteedi hindamisel
Acid igneous rock fragments: composed of quartz, alkali feldspar, plagioclase feldspar, and occasional muscovite/and or biotite mica, amphibole, and microcline.
Goddesses, snake tubes, and plaques: analysis of ceramic ritual objects from the LM IIIC shrine at Kavousi
In the Tallinn laboratory, both quartz and alkali feldspars have been used in the OSL dating.
Application of OSL and [sup.10]Be techniques to the establishment of deglaciation chronology in Estonia/Optiliselt stimuleeritud luminestsentsmeetodi (OSL) ja berulliumimeetodi ([sup.10]Be) kasutamine mandrijaa taandumise kronoloogia tapsustamiseks Eestis
The most common rocks within the KZ-25 borehole are leucogranite and alkali feldspar syenite (Table 1).
The matrix porosity and related properties of a leucocratic granite from the Krudum Massif, West Bohemia
Tapponnier (1993), High cooling and denudation rates at Kongur Shan, eastern Pamir (Xinjiang, China) revealed by 40Ar/39Ar alkali feldspar thermochronology, Tectonics, 12, 1335-1346.
Spatial and Temporal Variation in Slip Rate along the Kongur Normal Fault, Chinese Pamir
The dyke a]so contains abundant phenocrysts and cognate xenocrysts of kaersutite, biotite, and magnetite, and xenocrysts of a]bite and alkali feldspar.
An Early Triassic [sup.40]Ar/[sup.39]Ar age for a camptonite dyke in Cambridge, Massachusetts, USA
Alkali feldspar occurs as interstitial grains or antiperthitic inclusions in plagioclase.
Anorogenic magmatic rocks in the Estonian crystalline basement/Eesti kristalse aluskorra anorogeensed magmakivimid

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