0086-21-58386256

Provenance of sediments in the northern shelf of the South China …

K-feldspar is a common rock-forming mineral that is likely representative of the source terranes and could offer a more unbiased constraint on the sediment routing system. ... 2007; Zhang et al., 2021a). Compared to zircon, K-feldspar is prone to both mechanical and chemical weathering (Wang et al., 2019; Zhang et al., 2021a), and partial ...

WhatsApp: +86 18221755073

Review of the Post-IR IRSL Dating Protocols of K-Feldspar

of K-Feldspar Junjie Zhang and Sheng-Hua Li * Department of Earth Sciences, The University of Hong Kong, Hong Kong 999077, China; [email protected] * Correspondence: [email protected] ... Compared to quartz, the infrared stimulated luminescence (IRSL) of K-feldspar has several advantages: the IRSL signal of K-feldspar saturates at higher dose ...

WhatsApp: +86 18221755073

Fractional crystallization of high-K arc magmas: biotite- versus

Biotite and K-feldspar fractionation in the alkaline arc series results in the moderation of K 2 O/Na 2 O values and LILE concentrations with increasing SiO 2 as compared to the more common calc-alkaline series characterized by amphibole and plagioclase crystallization and strong increases in K 2 O/Na 2 O values. Lastly, we suggest that common ...

WhatsApp: +86 18221755073

Rounding of Quartz and K-Feldspar Sand From Beach to Dune …

Sand samples were collected from seven different locations along the California and Oregon coastlines where beach sediments and eolian coastal dunes are in close proximity (< 0.5 km) to each other. Beach sand was collected from the swash zone and dune sand was taken from the crests or lee faces of dunes. Loose sand was impregnated with epoxy and thin …

WhatsApp: +86 18221755073

K isotopic fractionation in K-feldspar: Effects of mineral …

a significant role in the K isotopic behavior of K-feldspar. The correlations of δ41K with SiO 2 and Al 2 O 3 contents are attributed to the difference in K-O bond strengths. Compared to K-feldspar, the K content could be a better proxy for constraining the δ 41K of plagioclase. Our results demonstrate that the δK of

WhatsApp: +86 18221755073

(PDF) ORIGIN OF K-FELDSPAR MEGACRYSTS IN PHULAD …

K-M) contd.: Photomicrographs of Phulad granite in cross polarized light showing K) inclusions also associated with K-feldspar grain boundary, L) large augen shaped K-feldspar megacrysts with ...

WhatsApp: +86 18221755073

COMPARISON OF EQUIVALENT DOSES OBTAINED WITH …

Compared with quartz, the infra-red stimulated luminescence (IRSL) signal of K-feldspar has several advantages, such as high signal intensity, high internal dose rate, late saturation and …

WhatsApp: +86 18221755073

K-feldspar

K-feldspar, Quartz and Biotite in a Granite. This view shows two large flakes of brownish green biotite and minor hornblende (darker smaller grains) near the left edge; the hornblende does not have a distinctive appearance. The biotite has a pebbly texture and micaceous cleavage.The right half of the view contains a large grain of clear to cloudy K-feldspar.

WhatsApp: +86 18221755073

Feldspars

Small pieces of albite in K-feldspar are called perthite, the reverse is antiperthite. By comparison, K-feldspars mix very well with Ba-feldspars. The ternary plot of possible feldspar compositions. The small black labels are old (and discouraged) feldspar names, the % shows the content of albite component (so basically the content of Na in ...

WhatsApp: +86 18221755073

K Feldspar: Mineral information, data and localities.

ID Species Reference Link Year Locality Pressure (GPa) Temp (K) 0000887: Hyalophane: Viswanathan K, Kielhorn H M (1983) Al,Si distribution in a ternary (Ba,K,Na)-feldspar as determined by crystal structure refinement Celsian-rich American Mineralogist 68 122-124 1983: Yugoslavia: 0: 293: 0009608: Hyalophane

WhatsApp: +86 18221755073

Linking Taiwan to the Cathaysia Block during the Cenozoic: …

K-feldspar is a common mineral in numerous clastic rocks and is a significant component of sediments. Compared to the widely used detrital zircon, the K-feldspar grains are more likely to preserve a first-cycle signal that is derived directly from the source (Tyrrell et al., ...

WhatsApp: +86 18221755073

Feldspars

Feldspars belong to the tectosilicates, sometimes referred also as network silicates. Their structure is based on three dimensional network of SiO4 tetrahedrons which are partially replaced by AlO4tetrahedrons. Feldspars form monoclinic or triclinic crystals. They are divided into groups of the disordered (high) and the ordered (lo…

WhatsApp: +86 18221755073

High-temperature inter-mineral potassium isotope fractionation

For the first time, we found large inter-mineral fractionation of K isotopes in natural samples (up to 1.072‰), where plagioclase displays a significant enrichment of heavier K …

WhatsApp: +86 18221755073

Thermodegradation Modeling in Simplified K-Feldspar Systems

K-feldspar Decomposition: K-feldspar is a common mineral found in igneous and metamorphic rocks. It is a silicate mineral with the chemical formula KAlSi3O8. ... A rapid heating rate can lead to the formation of different products compared to a slow heating rate. The decomposition process is also influenced by the presence of other minerals and ...

WhatsApp: +86 18221755073

K isotopic fractionation in K-feldspar: Effects of mineral …

Compared to K-feldspar, the K content could be a better proxy for constraining the δ41K of plagioclase. Our results demonstrate that the δ41K of K-feldspar is dependent on its mineral …

WhatsApp: +86 18221755073

Investigation of the hydrothermally altered K-feldspar use in slag

This paper explores the use of nano-structured, hydrothermally altered K-feldspar, known as a multi-phase material (MPM), as a precursor in alkali-activated systems based on ground …

WhatsApp: +86 18221755073

The ice-nucleating ability of quartz immersed in water and its

Abstract. Mineral dust particles are thought to be an important type of ice-nucleating particle (INP) in the mixed-phase cloud regime around the globe. While K-rich feldspar (K-feldspar) has been identified as being a particularly important component of mineral dust for ice nucleation, it has been shown that quartz is also relatively ice-nucleation active. Given quartz typically makes up …

WhatsApp: +86 18221755073

Comparison of Equivalent Doses Obtained with Various post-IR …

OSL dating are quartz and K-feldspar. Compared with . quartz, the infra-red stimulated luminescence (IRSL) signal of K-feldspar has se veral adva ntages, such a s high .

WhatsApp: +86 18221755073

K isotopic fractionation in K-feldspar: Effects of mineral chemistry

The correlations of δ41K with SiO2 and Al2O3 contents are attributed to the difference in K-O bond strengths. Compared to K-feldspar, the K content could be a better proxy for constraining the δ41K of plagioclase. Our results demonstrate that the δ41K of K-feldspar is dependent on its mineral chemistry, and its K isotopic composition may be ...

WhatsApp: +86 18221755073

Deep-time thermal history of the Great Unconformity in the Grand …

In all locations, models constrained only by ZHe data have limited resolving power for the past ∼600 m.y., compared to models that combine K-feldspar 40Ar/39Ar and ZHe data, which extends the recorded history into the Mesoproterozoic. Our model results suggest that two regional basement unroofing events occurred.

WhatsApp: +86 18221755073

Rheology of dry K-feldspar aggregates at high temperature

Quartz and feldspar are the two most abundant minerals in the continental crust. The rheology of quartz and feldspar has been used to approximate the rheology of the upper and the lower crust, respectively. However, compared with quartz and plagioclase, the rheology of K-feldspar (Kfs) is much less characterized. We present here systematic axial compression deformation …

WhatsApp: +86 18221755073

The ice-nucleating ability of quartz immersed in water and its

1 1 The ice-nucleating ability of quartz immersed in water and its 2 atmospheric importance compared to K-feldspar 3 4 Alexander D. Harrison1, Katherine Lever1, Alberto Sanchez-Marroquin1, Mark A. Holden1,2*, 5 Thomas F. Whale1,2, Mark D. Tarn1,3, James B. McQuaid1 and Benjamin J. Murray1 6 1School of Earth and Environment, University of Leeds, Leeds, …

WhatsApp: +86 18221755073

Selective flotation of K-feldspar from Na-feldspar in alkaline

The K-feldspar was selectively floated from Na-feldspar at pH 10.5–11.6 with NaOH as pH adjuster/modifier and Brij58 as frother, but without any additional collector other than the …

WhatsApp: +86 18221755073

The ice-nucleating ability of quartz immersed in water and its

1 1 The ice-nucleating ability of quartz immersed in water and its 2 atmospheric importance compared to K -feldspar 3 4 Alexander D. Harrison 1, Katherine Lever 1, Alberto Sanchez -Marroqu in1, Mark A. Holden 1,2*, 5 Thomas F. Whale 1,2, Mark D. Tarn 1, James B. McQuaid 1 and Benjamin J. Murray 1 6 1School of Earth and Environment, University of Leeds, Leeds, …

WhatsApp: +86 18221755073

K-Ar geochronology for hydrothermal K-feldspar within …

Thus, we compared the K-Ar age of the hydrothermal K-feldspar with that of the magmatic K-feldspar. The magmatic K-feldspar of sample MIU1-2 (-261.9 masl of borehole MIU-1) ( Yuguchi et al., 2010 ), which was obtained near the samples of this study, has the K-Ar age of 68.2 ± 3.4 Ma (unpublished data collected by the Japan Atomic Energy Agency).

WhatsApp: +86 18221755073

Field calibration of 40Ar/39Ar K-feldspar multiple diffusion domain

Numerous studies suggest that 40Ar/39Ar K-feldspar analyses record continuous thermal histories from ∼300 °C to 150 °C due to the presence of multiple diffusion domains (MDDs).

WhatsApp: +86 18221755073

ACP

Abstract. The relation between the mineralogical characteristics of size-selected feldspar particles from 50 to 800 nm and their ability to act as ice-nucleating particles (INPs) in the immersion mode is presented. Five polymorph members of K-feldspar (two microclines, orthoclase, adularia and sanidine) and four plagioclase samples (three labradorites and a …

WhatsApp: +86 18221755073

Pb isotopic zoning of K-feldspar megacrysts determined by Laser

When compared to other rocks from the TMP, the Pb isotopic composition of the K-feldspar megacrysts overlaps with the volcanic district of Tolfa-Manziana (southernmost outcrop of the TMP; Pinarelli, 1991) and the rhyolitic volcanic centres of San Vincenzo and Roccastrada (Fig. 1; Vollmer, 1977) and has similar 208 Pb/ 204 Pb to lamproitic rocks ...

WhatsApp: +86 18221755073

Review of the Post-IR IRSL Dating Protocols of K-Feldspar

Compared to quartz, the infrared stimulated luminescence (IRSL) of K-feldspar saturates at higher dose, which has great potential for extending the dating limit.

WhatsApp: +86 18221755073

Cesium Fractionation in Miarolitic Pegmatites: A Reevaluation of K

The K/Cs ratio of the synthetic K-feldspar was compared to modeled K/Cs ratios for K-feldspars formed from a water-saturated melt in which the initial Cs concentration (Co) of the melt was ...

WhatsApp: +86 18221755073

Solutions