Variation in Major and Trace Elements of Primary WÖhlerite As an Indicator of the Origin of Pegmatites in the Larvik Plutonic Complex, Norway

Sunde, Øyvind; Friis, Henrik; Andersen, Tom

doi:10.3749/canmin.1700050

Cited by 6 publications

(6 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nepheline syenite in dykes associated with pegmatites is related to an evolved derivate from RS 6 larvikite (Groome, 2017). Chemical variation between pegmatites situated in larvikite with or without nepheline syenite show that these rocks are related to a common source (Sunde et al, 2018). Furthermore, the major and trace element signature of wöhlerites from the different pegmatites within the Sagåsen quarry are identical, supporting a common source despite their difference in size, orientation, contact relations and mineralogy (Sunde et al, 2018).…”

Section: Timing Of Pegmatite and Nepheline Syenite Emplacementmentioning

confidence: 97%

“…Chemical variation between pegmatites situated in larvikite with or without nepheline syenite show that these rocks are related to a common source (Sunde et al, 2018). Furthermore, the major and trace element signature of wöhlerites from the different pegmatites within the Sagåsen quarry are identical, supporting a common source despite their difference in size, orientation, contact relations and mineralogy (Sunde et al, 2018). Therefore, our current knowledge suggests that both nepheline syenite and pegmatites in RS 6 were emplaced within a short, but similar time-frame.…”

Section: Timing Of Pegmatite and Nepheline Syenite Emplacementmentioning

confidence: 99%

See 1 more Smart Citation

Pegmatites of the Larvik Plutonic Complex, Oslo Rift, Norway: field relations and characterisation

Sunde¹,

Friis²,

Andersen³

2019

NJG

Self Cite

View full text Add to dashboard Cite

The Larvik Plutonic Complex (LPC) contains pegmatites with a wide array of mineral assemblages and morphological features. The pegmatites have traditionally been described as nepheline syenite and syenite pegmatites which carry agpaitic or miaskitic mineral assemblages, respectively. However, several pegmatites fall outside this simple characterisation due to 'agpaitic-like' late magmatic mineral assemblages such as hiortdahlite and eudialyte group minerals. Morphological and mineralogical differences between pegmatites are not unique to, or related with, specific areas of the LPC. Compositional variation and deformation features of the host pluton are the main mechanisms for differing morphology and mineral assemblages between LPC pegmatites. Natrolite replacement of feldspathoid is the most common alteration feature in the nepheline syenite pegmatites. The extent of alteration is closely associated with crystallisation of saccharoidal albite and aegirine. Detailed description of a nepheline syenite pegmatite situated in the Sagåsen quarry provides new insights into the internal evolution and mineral distribution of a large representative pegmatite body. The most important mechanism driving hydrous alteration is the crystallisation of anhydrous primary minerals which leads to an immiscible hydrous fluid driving in situ alterations of primary mineral assemblages.

show abstract

Section: Timing Of Pegmatite and Nepheline Syenite Emplacementmentioning

confidence: 97%

Section: Timing Of Pegmatite and Nepheline Syenite Emplacementmentioning

confidence: 99%

Pegmatites of the Larvik Plutonic Complex, Oslo Rift, Norway: field relations and characterisation

Sunde¹,

Friis²,

Andersen³

2019

NJG

Self Cite

View full text Add to dashboard Cite

show abstract

“…This is confirmed by subsequent crystal structure refinements in which the Nb site is populated by a significant amount of Mn or Mg (Bellezza et al , 2012; Biagioni et al , 2012). Andersen et al (2010) and Sunde et al (2018) showed only minor chemical variations in wöhlerite from different localities in the Larvik plutonic complex in Norway.…”

Section: Historical Synopsismentioning

confidence: 97%

“…Marianoite was described as monoclinic, P2 1 , with a = 10.846, b = 10.226, c = 7.273 Å and β = 109.33°. The highest Nb content reported by Chakhmouradian et al (2008) for marianoite is 1.019 apfu, which is roughly 0.3 apfu more than in wöhlerite from the Langesundsfjord (Sunde et al, 2018). The approval of marianoite as a valid mineral species was based on the assumption that both Zr and Nb are disordered on the two smallest octahedral sites [average bond lengths: 2.031 (X6) and 2.080 Å (X1)] occurring in the structure.…”

Section: Discreditation Of Marianoitementioning

confidence: 99%

“…Wöhlerite, ideally Na 2 Ca 4 ZrNb(Si 2 O 7 ) 2 O 3 F, was reported initially by Scheerer (1843) from the syenite pegmatites occurring on Løvøya island, Brevig area, Langesundsfjord, Norway. Wöhlerite is an abundant mineral throughout the Langesundsfjord (Andersen et al , 2010; Larsen, 2010; Sunde et al , 2018), though also from other syenites and carbonatites around the world (e.g. Mariano and Roeder, 1989; Keller and Williams, 1995; Bellezza et al , 2012; Biagioni et al , 2012; Melluso et al , 2017; Guarino et al , 2019).…”

Section: Historical Synopsismentioning

confidence: 99%

See 1 more Smart Citation

Nomenclature of wöhlerite-group minerals

Friis

Mills

2022

MinMag

Self Cite

View full text Add to dashboard Cite

A nomenclature and classification scheme for wöhlerite group minerals has been established.The general formula of minerals belonging to this group is given by X 8 (Si 2 O 7 ) 2 W 4 , where X = Na + , Ca 2+ , Mn 2+ , Ti 4+ , Zr 4+ and Nb 5+ ; and W = Fand O 2-. In addition, they may incorporate significant amounts of Mg 2+ , Fe 2+ , Y 3+ and REE 3+ , where REE are the lanthanides. The main structural feature of these minerals is the four columns wide octahedral walls, that are interconnected through corner sharing and via the disilicate groups. The wöhlerite group minerals crystallise in different unit-cell settings and symmetries, depending on the cationic ordering in the octahedral walls and the relative position of the disilicate groups. Different combinations of X and W constituents should be regarded as separate mineral species. In the case of coupled heterovalent substitutions at different crystallographic sites, it is advised to use the site-total charge approach to determine the correct endmember composition. Due to their structural and chemical features, wöhlerite group minerals can easily form crystals with several micro domains, showing different crystal structures and chemical compositions.In addition, the crystallisation of polytypes is relatively common, although they should not be regarded as distinct mineral species. To date, ten minerals belonging to the wöhlerite group are considered as valid species: baghdadite, burpalite, cuspidine, hiortdahlite, janhaugite, låvenite, moxuanxueite, niocalite, normandite and wöhlerite. Låvenite and normandite are isostructural and are respectively the Zr and Ti endmembers of a solid-solution series. Marianoite is discredited, as it is corresponding to wöhlerite. The ideal formula of hiortdahlite is revised as Na 2 Ca 4 (Ca 0.5 Zr 0.5 )Zr(Si 2 O 7 ) 2 OF 3 , with one cationic site characterised by a valency-imposed double site-occupancy. These changes have been approved by the IMA-CNMNC (Proposal 20-D).

show abstract

Chemical controls on niobium and zirconium mobility inferred from dissolution experiments on wöhlerite in alkaline silica-undersaturated melts

et al. 2023

View full text Add to dashboard Cite

Variation in Major and Trace Elements of Primary WÖhlerite As an Indicator of the Origin of Pegmatites in the Larvik Plutonic Complex, Norway

Abstract: Last but not least, a huge thanks to my family and friends who have continuously supported me over the years. Who knows, maybe one day knowing a little bit about nepheline syenite pegmatites might become useful.

Cited by 6 publications

References 43 publications

Pegmatites of the Larvik Plutonic Complex, Oslo Rift, Norway: field relations and characterisation

Pegmatites of the Larvik Plutonic Complex, Oslo Rift, Norway: field relations and characterisation

Nomenclature of wöhlerite-group minerals

Chemical controls on niobium and zirconium mobility inferred from dissolution experiments on wöhlerite in alkaline silica-undersaturated melts

Contact Info

Product

Resources

About