In Situ LA-ICP-MS Analysis of Minerals Hosted by Late Cenozoic Basaltic Rocks from Thailand

Shortly after the cessation of seafloor spreading, intraplate magmatism affected large areas in the South China Sea (SCS) region. The origin and geodynamic setting of the post-spreading volcanism is still in debate, for many previous studies have focused on petrogenesis and mantle source of the late Cenozoic basalts from the SCS region. In this study, we obtained in situ major element compositions (by using Electron microprobe analysis—EMPA) and trace element compositions (by using laser ablation inductively coupled plasma mass spectrometry— LA-ICP-MS) for minerals (clinopyroxenes (Cpx), plagioclases (Pl), and olivines (Ol)) hosted by late Cenozoic basaltic rocks from Thailand. The results showed that the olivines had forsterite contents between 60.12% and 84.74%. Clinopyroxene were diopside and augite, and they were enriched in light rare earth elements (LREEs) (LaN/YbN = 1.93–4.27) and depleted in large-ion lithophile elements (LILEs). Mineral compositions (mainly based on clinopyroxene) confirmed that these late Cenozoic basaltic rocks were of an intraplate affinity and were similar to contemporaneous basaltic fields in the SCS region (Southern Vietnam, Northern Hainan, and SCS seamounts). Plagioclases were predominantly labradorite, with a few andesine and bytownite, and they were enriched in LREEs and Ba, Sr, and Pb, and most of them exhibited strong positive Eu anomalies. The source lithology of Thailand basaltic rocks could be garnet pyroxenite. The mantle potential temperature beneath Thailand is in the range of 1448–1467 °C, which can be comparable to those beneath Southern Vietnam and Northern Hainan, indicating the Thailand basaltic rocks could be produced by the Hainan mantle plume. In addition, the crystallization temperature of clinopyroxenes (1145–1214 °C) and plagioclase (1067–1133 °C) and their composition characteristics indicate that the magmatic processes have a conspicuous characteristic of fast rate of magma upwelling. Thus, we proposed that the deep geodynamic setting of Thailand late Cenozoic basaltic rocks is similar to those of the whole SCS region, and Hainan mantle plume plays a significant role in the petrogenesis of these basaltic rocks.

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Hainan mantle plume produced late Cenozoic basaltic rocks in Thailand, Southeast Asia

Scientific Reports ◽

10.1038/s41598-018-20712-7 ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 15

Author(s):

Quanshu Yan ◽

Xuefa Shi ◽

Ian Metcalfe ◽

Shengfa Liu ◽

Taoyu Xu ◽

...

Keyword(s):

Southeast Asia ◽

Mantle Plume ◽

Late Cenozoic ◽

Basaltic Rocks ◽

Hainan Mantle Plume

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U–Pb geochronology of epidote by LA–ICP–MS as a tool for dating hydrothermal-vein formation

10.5194/gchron-2020-27 ◽

2020 ◽

Author(s):

Veronica Peverelli ◽

Tanya Ewing ◽

Daniela Rubatto ◽

Martin Wille ◽

Alfons Berger ◽

...

Keyword(s):

Inductively Coupled Plasma ◽

A Priori ◽

Swiss Alps ◽

Hydrothermal Vein ◽

Isotopic Compositions ◽

Vein Formation ◽

Icp Ms ◽

Wide Range ◽

Primary Reference

Abstract. Monoclinic epidote is a low-µ (µ = 283U / 204Pb) mineral occurring in a variety of geological environments, participating in many metamorphic reactions and stable throughout a wide range of pressure–temperature conditions. Despite containing fair amounts of U, its use as a U–Pb geochronometer has been hindered by the commonly high contents of initial Pb with isotopic compositions that cannot be assumed a priori. We present U–Pb geochronology of hydrothermal-vein epidote spanning a wide range of Pb (3.9–190 µg g−1), Th (0.009–38 µg g−1) and U (2.6–530 µg g−1) contents and with µ values between 7–510 from the Albula area (eastern Swiss Alps), from the Grimsel area (central Swiss Alps) and from the Heyuan fault (Guangdong province, China). The investigated epidote samples show appreciable fractions of initial Pb that vary to different extents. A protocol has been developed for in situ U–Pb dating of epidote by spot-analysis laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) with a magmatic allanite as primary reference material. The suitability of the protocol and the reliability of the measured isotopic ratios have been ascertained by independent measurements of 238U / 206Pb and 207Pb / 206Pb ratios respectively by quadrupole and multicollector ICP–MS applied to epidote micro-separates digested and diluted in acids. For age calculation, we used the Tera–Wasserburg (207Pb / 206Pb–238U / 206Pb) diagram, which does not require corrections for initial Pb and provides the initial 207Pb / 206Pb ratio if all intra-sample analyses are co-genetic. Petrographic and microstructural data indicate that the calculated ages date the crystallization of vein epidote from a hydrothermal fluid and that the U–Pb system was not reset to younger ages by later events. Vein epidote from the Albula area formed in the Paleocene (62.7 ± 3.0 Ma) and is related to Alpine greenschist-facies metamorphism. The Miocene (19.1 ± 4.0 Ma and 16.9 ± 3.7 Ma) epidote veins from the Grimsel area formed during the Handegg phase (22–17 Ma) of the Alpine evolution of the Aar Massif. Identical initial 207Pb / 206Pb ratios reveal homogeneity in Pb isotopic compositions of the fluid across ca. 200 m. Vein epidote from the Heyuan fault is Cretaceous in age (108.1 ± 8.4 Ma) and formed during the early movements of the fault. In situ U–Pb analyses of epidote returned reliable ages of otherwise undatable epidote-quartz veins. The Tera–Wasserburg approach has proven pivotal for in situ U–Pb dating of epidote and the decisive aspect for low age uncertainties is the variability in intra-sample initial Pb fractions.

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High-resolution LA-ICP-MS trace-element mapping of magmatic biotite: A new approach for studying syn- to post-magmatic evolution

The Canadian Mineralogist ◽

10.3749/canmin.1900101 ◽

2020 ◽

Vol 58 (3) ◽

pp. 293-311 ◽

Cited By ~ 2

Author(s):

Zeinab Azadbakht ◽

David R. Lentz

Keyword(s):

New Brunswick ◽

Trace Element ◽

Inductively Coupled Plasma ◽

Fluid Phase ◽

New Approach ◽

Inductively Coupled ◽

Icp Ms ◽

Magma Crystallization ◽

Topaz Granite

ABSTRACT Biotite grains from 22 felsic intrusions in New Brunswick were mapped in situ using a laser ablation-inductively coupled plasma-mass spectrometer (LA-ICP-MS). We investigated the extent to which biotite can retain its magmatic zoning patterns and, where zoning does exist, how it can be used to elucidate early to late stage, syn-magmatic to post-crystallization processes. Although the major element and halogen contents of the examined biotite phenocrysts are homogeneous, two-thirds of the grains display trace-element zoning for Ba, Rb, and Cs. The results also indicated that zoning is better retained in larger grains (i.e., > 500 × 500 μm) with minimal alteration and mineral inclusions. An exceptionally well-zoned Li-rich siderophyllite from the Pleasant Ridge topaz granite in southwestern New Brunswick shows Ti, Ta, Sn, W, Cs, Rb, and V (without Li or Ba) zoning. Cesium values increase from 200 to 1400 ppm from core to rim. Conversely, Sn and W values decrease toward the rim (50 to 10 and 100 to 10 ppm, respectively). Tantalum and Ti values show fewer variations but drop abruptly close to the rim of the grain (100 to 20 and 2000 to 500 ppm, respectively). These observations may indicate crystallization of mineral phases with high partition coefficients for these highly incompatible elements (except Ti) (e.g., cassiterite and rutile) followed by fractionation of a fluid phase at a later stage of magma crystallization. The preservation of zoning may indicate rapid cooling post-crystallization of the parent magma.

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Petrogenesis of Late Cenozoic basaltic rocks from southern Vietnam

Lithos ◽

10.1016/j.lithos.2016.12.008 ◽

2017 ◽

Vol 272-273 ◽

pp. 192-204 ◽

Cited By ~ 24

Author(s):

A-Rim An ◽

Sung Hi Choi ◽

Yongjae Yu ◽

Der-Chuen Lee

Keyword(s):

Late Cenozoic ◽

Basaltic Rocks ◽

Southern Vietnam

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Geochemical researches in situ (LA-ICP-MS) of accessory and ore minerals from multimetal (PGE, Cu-Ni) deposits in the Arctic zone (Fennoscandian Shield) of the Russian Federation

10.5194/egusphere-egu2020-13123 ◽

2020 ◽

Author(s):

Svetlana Drogobuzhskaya ◽

Tamara Bayanova ◽

Andrey Novikov

Keyword(s):

Inductively Coupled Plasma ◽

Arctic Region ◽

Sulfide Minerals ◽

Fennoscandian Shield ◽

The Arctic ◽

Local Analysis ◽

Icp Ms ◽

Ore Minerals ◽

Rfbr Grant

The laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) is a unique method for local analysis that allows studying mineral grains in situ. The aims of these geochemical researches are to estimate concentrations and distributions of REE, Hf, U, Th, Y, Ti, PGE and other elements in accessory and ore minerals from complex deposits in the Arctic region (Fennoscandian Shield), using the LA-ICP-MS local analysis of trace elements. Accessory minerals of zircon and baddeleyite are much valued to study distributions of rare and rare earth elements (REE). Besides, pyrite, pentlandite, pyrrhotite and other sulfides are important for determining platinum-group elements (PGE), REE, etc.The electron (LEO-1415) and optic (LEICA OM 2500 P, camera DFC 290) spectroscopy have been applied to study the morphology of the samples. Analytical points have been selected on baddeleyite, zircon crystals and sulfide minerals based on analyses of their BSE, CL and optical images. REE, PGE and other elements have been estimated in situ by ICP-MS, using an ELAN 9000 DRC-e (Perkin Elmer) quadrupole mass spectrometer equipped with UP-266 MA&#1057;RO laser (New Wave Research).More than 19 elements were profiled during each measurement in zircon or baddeleyite. For the first time, LA-ICP-MS techniques have been applied to estimate PGE, REE and other (S, Cr, Fe, Cu, Ni, Co, As, Se, Mo, Cd, Sn, Sb, Re, Te, Tl, Hf, W, Bi, Pb, Th, U) elements in sulfide minerals. NIST 610, NIST 612 and tandem graduation (using solutions), considering sensitivity coefficients of isotopes have been used to check the accuracy of estimations. Fe, Ni and Cu have been used as internal standards, being most evenly distributed elements in minerals, when concentrations of elements in sulphides were calculated. The estimates have been carried out, using inter-laboratory standards of chalcopyrite, pentlandite and pyrrhotite, which had been preliminarily prepared and studied using micro probe analysis (Cameca MS-46).These techniques had been used to estimate elements in zircon extracted from basic and acidic rocks of the Lapland belt (1.9 Ga), the Keivy zone (2.7 Ga), the Kandalaksha and Kolvitsa zone (2.45 Ga) and from the Cu-Ni deposit (Terrace, Mt. Nyud, 2.5 Ga). Novel techniques have been used to analyze baddeleyite from rocks of layered PGE intrusions of the Monchegorsk ore area (2.5 Ga) and carbonatites of Kovdor and Vuoriyarvi (380 Ma). Elaborated LA-ICP-MS techniques have been applied to provide in situ measurements of PGE, Au, Ag, siderophile and chalcophile elements in sulphide minerals from the Pechenga and Allarechka Cu-Ni deposits (1.98 Ga), Fedorova Tundra and Severny Kamennik PGE deposits (2.5 Ga).The scientific researches are supported by RFBR Grant No 18-05-70082, scientific themes 0226-2019-0032 and 0226-2019-0053.

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Determination of impurities in micro-amounts of silver alloys by electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) after in-situ-digestion in the graphite furnace

Fresenius Journal of Analytical Chemistry ◽

10.1007/s002160050597 ◽

1997 ◽

Vol 359 (4-5) ◽

pp. 404-406 ◽

Cited By ~ 13

Author(s):

C. Moor ◽

Peter Boll ◽

Sonja Wiget

Keyword(s):

Inductively Coupled Plasma ◽

Graphite Furnace ◽

Electrothermal Vaporization ◽

Silver Alloys ◽

Inductively Coupled ◽

Icp Ms ◽

Plasma Mass Spectrometry ◽

Determination Of Impurities

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In-situ isotopic ratio analysis of iron using laser ablation-multiple collector-inductively coupled plasma mass spectrometry (LA-MC-ICP-MS)

Journal of Analytical Atomic Spectrometry ◽

10.1039/b100946j ◽

2001 ◽

Vol 16 (5) ◽

pp. 487-491 ◽

Cited By ~ 26

Author(s):

Takafumi Hirata ◽

Takeshi Ohno

Keyword(s):

Mass Spectrometry ◽

Laser Ablation ◽

Inductively Coupled Plasma ◽

Isotopic Ratio ◽

Ratio Analysis ◽

Inductively Coupled ◽

Icp Ms ◽

Plasma Mass Spectrometry

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High spatial resolution in situ U–Pb dating using laser ablation multiple ion counting inductively coupled plasma mass spectrometry (LA-MIC-ICP-MS)

Journal of Analytical Atomic Spectrometry ◽

10.1039/c6ja00387g ◽

2017 ◽

Vol 32 (5) ◽

pp. 975-986 ◽

Cited By ~ 14

Author(s):

Lie-Wen Xie ◽

Jin-Hui Yang ◽

Qing-Zhu Yin ◽

Yue-Heng Yang ◽

Jing-Bo Liu ◽

...

Keyword(s):

Spatial Resolution ◽

Inductively Coupled Plasma ◽

High Spatial Resolution ◽

Zircon Age ◽

Analytical Technique ◽

Inductively Coupled ◽

Rapid Measurement ◽

Icp Ms ◽

Plasma Mass Spectrometry

A new LA-MIC-ICP-MS analytical technique has been developed for the rapid measurement of 206Pb/238U zircon age (<1%, 2s) at a high spatial resolution. We show that this technique can be routinely employed to date U–Pb in small and/or complex zircons, providing a powerful tool for geochronology.

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Determination of Zr isotopic ratios in zircons using laser-ablation multiple-collector inductively coupled-plasma mass-spectrometry

Journal of Analytical Atomic Spectrometry ◽

10.1039/c9ja00192a ◽

2019 ◽

Vol 34 (9) ◽

pp. 1800-1809 ◽

Cited By ~ 13

Author(s):

Wen Zhang ◽

Zaicong Wang ◽

Frédéric Moynier ◽

Edward Inglis ◽

Shengyu Tian ◽

...

Keyword(s):

Mass Spectrometry ◽

Laser Ablation ◽

Inductively Coupled Plasma ◽

Isotopic Ratios ◽

Inductively Coupled ◽

Icp Ms ◽

Plasma Mass Spectrometry ◽

Isotope Variation

An in situ Zr isotopic analytical method for zircons was developed using LA-MC-ICP-MS to reveal the Zr stable isotope variation in the complex mineral crystallization history.

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