Growth of quartz with high aluminum concentration

Larkin, John J.; Armington, A.F.; O’Connor, John J.; Lipson, Herbert G.; Horrigan, J.A.

doi:10.1016/0022-0248(82)90182-8

Cited by 8 publications

(4 citation statements)

References 2 publications

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“…ICP-MS results (Table 1) show high aliquots of Al +3 and Li + , Na + and K + as positively charged interstitial cations. The growth mechanisms of quartz are indeed influenced by Al content, and the pronounced zoning occurs in a situation in which the Al amount is large [25,56,57]. Moreover, the high concentrations of Fe +3/+2 and Ti +4 suggest that they may have a role in the luminescence emission since both (Fe +3 and Ti +4 ) can substitute silicon atoms in the lattice due to their small ion radii.…”

Section: Resultsmentioning

confidence: 99%

Unusual Luminescence of Quartz from La Sassa, Tuscany: Insights on the Crystal and Defect Nanostructure of Quartz

Ricci

Monti

Pagano³

et al. 2021

Minerals

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Quartz from La Sassa (Tuscany, Italy) presents a unique luminescence related to intrinsic and extrinsic defects in the crystal lattice due to the growth mechanisms in hydrothermal conditions. The bright fluorescence under the UV lamp was apparent to collectors since the early 1970s, and it entered the literature as a reference case of yellow-luminescent quartz. Early reports present the history of the discovery, the geological context, and preliminary luminescence measurements of the quartz nodules, suggesting various activators as potentially responsible of the peculiar luminescence effects: uranyl groups (UO22+), rare earths (Tb3+, Eu3+, Dy3+, Sm3+, Ce3+) and polycyclic aromatic compounds (PAH). Here, we report a full investigation of the La Sassa material, by a multi-analytical approach encompassing cathodoluminescence optical microscopy (OM-CL), laser-induced fluorescence (LIF), wavelength resolved thermally stimulated luminescence (WR-TSL), trace elements analysis by mass spectrometry (ICP-MS) and Raman spectroscopy (RS). The results provide a significant step forward in the interpretation of the luminescence mechanisms: the main luminescent centres are identified as alkali-compensated (mainly Li+ and Na+, K+ and H+) aluminum [AlO4/M+]0 centres substituting for Si, where the recombination of a self-trapped exciton (STE) or an electron at a nonbridging oxygen hole centre (NBOHC) are active.

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Section: Resultsmentioning

confidence: 99%

Unusual Luminescence of Quartz from La Sassa, Tuscany: Insights on the Crystal and Defect Nanostructure of Quartz

Ricci

Monti

Pagano³

et al. 2021

Minerals

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“…Such nonequivalence in d 18 O values between different sectors could thus either be caused by a structural, crystallographic control on isotope fractionation, growth rate or kinetics, and/or by growth mechanisms (Dowty, 1976;Watson and Liang, 1995;Yoshimura and Kohra, 1976;Yoshimura et al, 1979;Larkin et al, 1982;Onasch and Vennemann, 1995;Watson, 2004;Jourdan et al, 2009), or by a combination of these.…”

Section: Face-related O-isotope Fractionationmentioning

confidence: 97%

“…Yoshimura et al (1979) and Larkin et al (1982) have previously suggested that growth mechanisms of quartz are influenced by the Al content. When the Al content is large, spiral growth is likely to occur, and this change from a normal step-wise growth may also influence the incorporation of O-isotopes, perhaps via a control on the type of ion that may be incorporated (see below).…”

Section: Growth Mechanismsmentioning

confidence: 98%

Oxygen isotope sector zoning in natural hydrothermal quartz

et al. 2009

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Oxygen isotope measurements using SIMS and laser-fluorination methods confirm the presence of concentric and sector zoning in low-temperature (200ºC to <400ºC) hydrothermal quartz from Alpine veins. While concentric zoning is most readily explained by changes in the chemical composition of the fluid or temperature of crystallization, the reasons for sector zoning are more difficult to explain. Relative enrichment in 18 O for crystallographically different sectors of quartz corresponds to m >r >z. Sector zoning is, however, largely limited to the exterior zones of crystals and/or to crystals with large Al (>1000 ppm) and trace element contents, probably formed at temperatures <250ºC. Differences in d 18 O between the prismatic (m) relative to the rhombohedral (r and z) growth sectors of up to 2% can be explained by a combination of a face-related crystallographic and/or a growth rate control. In contrast, isotopic sector zoning of up to about 1.5% amongst the different rhombohedral faces increases in parallel with the trace element content and is likely to represent disequilibrium growth. This is indicated by non-systematic, up to 2%, differences within single growth zones and the irregular, larger or smaller, d 18 O values (of several permil) of the exterior compared to the inner zones of the same crystals. Disequilibrium growth may be related to the large trace element content incorporated into the growing quartz at lower temperatures (<250ºC) and/or be related to fluid-vapour separation, allowing crystal growth from both a vapour as well as a liquid phase.

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“…This heterogeneity of isotopic values can reflect temperature variations or changes in fluid composition at microsite scale. Processes other than temperature and initial parent δ 18 O water may affect the δ 18 O of quartz/silica; including growth under disequilibrium conditions (Dickson, 1991), sector zoning (Jourdan et al, 2009), variable incorporation of trace Al in the quartz lattice due to a change from normal step-wise growth to spiral growth (Yoshimura et al, 1979;Larkin et al, 1982). In fibrous microquartz cements, minor δ 18 O variations could also be related to the occurrence of OH-related impurities.…”

Section: Insights From the Partition Between Length-slow And Length-fmentioning

confidence: 99%

Diversity and origin of quartz cements in continental carbonates: Example from the Lower Cretaceous rift deposits of the South Atlantic margin

Teboul

Durlet

Girard

et al. 2019

Applied Geochemistry

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Silica precipitation in continental carbonates is a common process occurring during sedimentation and diagenesis. The Lower Cretaceous rift deposits of the South Atlantic equatorial margin, which are intensively explored by petroleum companies, provide good examples of such silicifications in carbonates, exhibiting a wide diversity of petrographic habit of early to late quartz cements. In order to understand the palaeoenvironmental and diagenetic conditions leading to this diversity, we integrated detailed petrography of diagenetic sequences and quartz habit with δ 18 O quartz measurements (by SIMS) of individual cements observed in samples from the offshore and onshore basins of the West African margin. The petrographic description highlights the omnipresence of early fibrous microquartz cements exhibiting either length-fast or length-slow habit, in addition to laminated microquartz and micro-or mega-quartz forms. Amongst the isotopic analysis, the δ 18 O quartz data show that length-slow cements are generally strongly enriched in 18 O (δ 18 O quartz ranging from 31 to 37‰ SMOW), whereas length-fast forms show less elevated values ACCEPTED MANUSCRIPT 2 (<32‰ SMOW). The highest δ 18 O quartz values for fibrous microquartz are interpreted to reflect precipitation from evaporated meteoric fluids at temperatures >25°C and <100°C. The alkalinity required to favor the precipitation of length-slow fibrous microquartz cements is probably related to fluid/rock interactions with underlying mantel-related or basic volcanic rocks. Such interactions would be in agreement with the recent geodynamic models of the South Atlantic passive margin. The length-fast fibrous microquartz associated with δ 18 O quartz values ranging from 27 to 32‰ SMOW, probably reflect precipitation from moderately to non evaporated, fairly neutral to acid, fluids. The partial dissolution of carbonate cements prior to quartz cementations represents the signature of those acidic conditions. We therefore suggest that acidic pH was obtained through fluid/rock interactions with the intermediate to acid volcanic rocks encountered along the palaeohydrological pathway. Other quartz phases, such as the megaquartz cement, exhibit highly variable δ 18 O quartz values ranging from 20 to 40 ‰. This variation may reflect significant variation in temperature conditions (between 100 and 200°C) or changes in fluid δ 18 O at the small scale. For these populations of non-fibrous quartz cement, the very high δ 18 O quartz values may reflect a contribution of fluids that have either suffered strong evaporation or strong water/rock interaction.

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Growth of quartz with high aluminum concentration

Cited by 8 publications

References 2 publications

Unusual Luminescence of Quartz from La Sassa, Tuscany: Insights on the Crystal and Defect Nanostructure of Quartz

Unusual Luminescence of Quartz from La Sassa, Tuscany: Insights on the Crystal and Defect Nanostructure of Quartz

Oxygen isotope sector zoning in natural hydrothermal quartz

Diversity and origin of quartz cements in continental carbonates: Example from the Lower Cretaceous rift deposits of the South Atlantic margin

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