U-Pb DATING OF HYDROTHERMAL TITANITE RESOLVES MULTIPLE PHASES OF PROPYLITIC ALTERATION IN THE OYU TOLGOI PORPHYRY DISTRICT, MONGOLIA

2020 ◽  
Vol 115 (8) ◽  
pp. 1605-1618
Author(s):  
Lisa Hart-Madigan ◽  
Jamie J. Wilkinson ◽  
Stephanie Lasalle ◽  
Robin N. Armstrong
Keyword(s):  
Inductively Coupled Plasma ◽  
Mineral Chemistry ◽  
Geodynamic Setting ◽  
Porphyry Deposits ◽  
Inductively Coupled ◽  
Close Proximity ◽  
Plasma Mass Spectrometry ◽  
History Of ◽  
Propylitic Alteration ◽  
World Class

Abstract Oyu Tolgoi is a world-class, Late Devonian porphyry district in southern Mongolia. Because of its age and geodynamic setting, it has undergone a complex geological history that includes major postmineralization magmatic-hydrothermal events in close proximity to the porphyry deposits. The propylitic alteration halos that surround the Cu-Au deposits contain widespread hydrothermal titanite, as do the younger altered volcanic and intrusive rocks. Here, we present a comprehensive laser ablation-inductively coupled plasma-mass spectrometry U-Pb study on in situ, propylitic titanite from the Oyu Tolgoi district. The results identify district-wide hydrothermal alteration episodes that coincide with known magmatic events: Devonian porphyry mineralization (~372 Ma); the intrusion of granodiorite plutons and andesite dikes in the Carboniferous (~320–310 Ma); and the emplacement of the Permian Khanbogd Granite alkaline batholith (~290 Ma). Both Carboniferous and Permian alteration events variably overprint the earlier porphyry alteration halo. Overdispersion in the U-Pb data from some samples, due to Pb and/or U mobility, makes interpretation of some titanite ages more difficult, but further exemplifies the complex alteration history of the district. We conclude that U-Pb dating of propylitic titanite is a viable means by which explorers can identify alteration within a prospect that is synchronous with potentially fertile intrusions of known age. The extent of the coeval propylitic alteration and its mineral chemistry can then be used to assess the likelihood of a major porphyry center being present.

scholarly journals The emplacement age of the Muntele Mare Variscan granite (Apuseni Mountains, Romania)

2009 ◽  
Vol 60 (6) ◽  
pp. 495-504 ◽  
Author(s):  
Ioan Balintoni ◽  
Constantin Balica ◽  
Monica Cliveţi ◽  
Li-Qiu Li ◽  
Horst Hann ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Variscan Orogeny ◽  
Weighted Mean ◽  
Apuseni Mountains ◽  
Inductively Coupled ◽  
Icp Ms ◽  
Plasma Mass Spectrometry ◽  
History Of ◽  
The Alps ◽  
Last Stage

The emplacement age of the Muntele Mare Variscan granite (Apuseni Mountains, Romania)Like the Alps and Western Carpathians, the Apuseni Mountains represent a fragment of the Variscan orogen involved in the Alpine crustal shortenings. Thus the more extensive Alpine tectonic unit in the Apuseni Mountains, the Bihor Autochthonous Unit is overlain by several nappe systems. During the Variscan orogeny, the Bihor Unit was a part of the Someş terrane involved as the upper plate in subduction, continental collision and finally in the orogen collapse and exhumation. The Variscan thermotectonic events were marked in the future Bihor Unit by the large Muntele Mare granitoid intrusion, an S-type anatectic body. Zircon U-Pb laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) dating yielded a weighted mean age of 290.9 ± 3.0 Ma and a concordia age of 291.1 ± 1.1 Ma. U-Pb isotope dilution zircon analyses yielded a lower intercept crystallization age of 296.6 + 5.7/-6.2 Ma. These two ages coincide in the error limits. Thus, the Muntele Mare granitoid pluton is a sign of the last stage in the Variscan history of the Apuseni Mountains. Many zircon grains show inheritance and/or Pb loss, typical for anatectic granitoid, overprinted by later thermotectonic events.

scholarly journals Rare and Critical Metals in Pyrite, Chalcopyrite, Magnetite, and Titanite from the Vathi Porphyry Cu-Au±Mo Deposit, Northern Greece

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 630
Author(s):  
Christos L. Stergiou ◽  
Vasilios Melfos ◽  
Panagiotis Voudouris ◽  
Lambrini Papadopoulou ◽  
Paul G. Spry ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Mineral Chemistry ◽  
Critical Metals ◽  
Northern Greece ◽  
Inductively Coupled ◽  
Porphyry Cu ◽  
Icp Ms ◽  
Quartz Monzonite ◽  
Ore Minerals ◽  
Plasma Mass Spectrometry

The Vathi porphyry Cu-Au±Mo deposit is located in the Kilkis ore district, northern Greece. Hydrothermally altered and mineralized samples of latite and quartz monzonite are enriched with numerous rare and critical metals. The present study focuses on the bulk geochemistry and the mineral chemistry of pyrite, chalcopyrite, magnetite, and titanite. Pyrite and chalcopyrite are the most abundant ore minerals at Vathi and are related to potassic, propylitic, and sericitic hydrothermal alterations (A- and D-veins), as well as to the late-stage epithermal overprint (E-veins). Magnetite and titanite are found mainly in M-type veins and as disseminations in the potassic-calcic alteration of quartz monzonite. Disseminated magnetite is also present in the potassic alteration in latite, which is overprinted by sericitic alteration. Scanning electron microscopy and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analyses of pyrite and chalcopyrite reveal the presence of pyrrhotite, galena, and Bi-telluride inclusions in pyrite and enrichments of Ag, Co, Sb, Se, and Ti. Chalcopyrite hosts bornite, sphalerite, galena, and Bi-sulfosalt inclusions and is enriched with Ag, In, and Ti. Inclusions of wittichenite, tetradymite, and cuprobismutite reflect enrichments of Te and Bi in the mineralizing fluids. Native gold is related to A- and D-type veins and is found as nano-inclusions in pyrite. Titanite inclusions characterize magnetite, whereas titanite is a major host of Ce, Gd, La, Nd, Sm, Th, and W.

Experimental assessment of the effect of temperature and salinity on elemental composition of otoliths using solution-based ICPMS

1995 ◽  
Vol 52 (7) ◽  
pp. 1421-1430 ◽  
Author(s):  
Anthony J. Fowler ◽  
Steven E. Campana ◽  
Simon R. Thorrold ◽  
Cynthia M. Jones
Keyword(s):  
Elemental Composition ◽  
Inductively Coupled Plasma ◽  
Somatic Growth ◽  
Early Life History ◽  
Effect Of Temperature ◽  
Micropogonias Undulatus ◽  
Inductively Coupled ◽  
Plasma Mass Spectrometry ◽  
History Of ◽  
Salinity Difference

Retrospective determination of the early life history of fish using the microelemental analysis of their otoliths is dependent upon understanding the factors that affect this elemental composition. Here, juvenile Atlantic croaker (Micropogonias undulatus) were reared under different treatments of temperature and salinity to determine their impacts on elemental inclusion rates in otoliths. Solution-based inductively coupled plasma mass spectrometry (ICPMS) was used to measure 21 isotopes in each otolith: isotopic concentrations ranged over seven orders of magnitude, and differed significantly amongst the temperature–salinity regimes. Univariate analyses identified 13 isotopes that contributed to these multivariate differences; the influence of temperature was stronger than that of salinity. Within each treatment there was a significant relationship between otolith microchemistry and otolith size. To some extent this confounded the interpretation of the between-treatment effect of temperature. In contrast, both the otolith and somatic growth rates were similar between the two salinity treatments, indicating that differences in elemental fingerprints were unambiguously related to the salinity difference, probably a response to the elemental concentrations in the tank water. Overall the study highlighted the current poor understanding of the mechanism of contamination of otoliths by trace elements and their incorporation into the otolith microstructure.

scholarly journals A Study of the Composition and Dissolution of Jianshui Purple Pottery in Yunnan, China

Crystals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1034
Author(s):  
Chang Liu ◽  
Heng Xie ◽  
Lei Nie ◽  
Hong Wang ◽  
Yuanyuan He
Keyword(s):  
Inductively Coupled Plasma ◽  
Theoretical Basis ◽  
Pottery Production ◽  
X Ray ◽  
Inductively Coupled ◽  
Dissolution Tests ◽  
Before And After ◽  
Plasma Mass Spectrometry ◽  
History Of ◽  
Composition Changes

Pottery is a gem in the history of human civilization and a crystallization of human wisdom. Yunnan Jianshui purple pottery is one of the four famous types of pottery in China, with a long history and superb craftsmanship. Used as tableware, research on the composition and element dissolution of pottery is extremely significant for production and health. This paper takes Jianshui purple pottery as its research object, samples its raw ores and finished products, and conducts X-ray fluorescence, scanning electron microscopy, inductively coupled plasma mass spectrometry experiments, and dissolution tests. The chemical composition, microstructure, and trace element concentrations of pottery before and after firing were measured. Results show that the dissolution of purple pottery under various use scenarios is low and meets health requirements. Combined with the characteristics of purple pottery, the composition changes and the mechanism of change before and after firing are discussed, which can be used as the theoretical basis for improving pottery production in the future.

Trace elements determined along single strands of hair by inductively coupled plasma mass spectrometry

1993 ◽  
Vol 39 (8) ◽  
pp. 1650-1655 ◽  
Author(s):  
J Yoshinaga ◽  
Y Shibata ◽  
M Morita
Keyword(s):  
Mass Spectrometry ◽  
Trace Elements ◽  
Flow Injection ◽  
Inductively Coupled Plasma ◽  
Small Volume ◽  
Distribution Profile ◽  
Inductively Coupled ◽  
Limit Of Determination ◽  
Plasma Mass Spectrometry ◽  
History Of

Abstract Flow injection-inductively coupled plasma mass spectrometry has been evaluated for determining the distribution profile of trace elements along a single strand of hair. Hair was cut into several mm long sections from follicle to the distal end. Each section was solubilized in a capped 1.5-mL polypropylene tube with small volume of nitric acid (typically 50 microL) at room temperature. After dilution an aliquot (50 microL) was introduced into the mass spectrometer by flow injection. The limit of determination was typically 5-50 pg with 5-10% precision (CV), depending on the element examined; this corresponds to sub-microgram/g concentrations of these elements in hair segments. Recent exposure and intake history of individuals to thallium or mercury could be reconstructed by this system.

Hydrochronology of a proposed deep geological repository for low- and intermediate-level nuclear waste in southern Ontario from U–Pb dating of secondary minerals: response to Alleghanian events

2020 ◽  
Vol 57 (4) ◽  
pp. 494-505 ◽  
Author(s):  
C.N. Sutcliffe ◽  
A.M. Thibodeau ◽  
D.W. Davis ◽  
Ihsan Al-Aasm ◽  
A. Parmenter ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Inductively Coupled Plasma ◽  
Ionization Mass ◽  
Southern Ontario ◽  
Inductively Coupled ◽  
Nuclear Site ◽  
Plasma Mass Spectrometry ◽  
History Of ◽  
Hydraulic Gradients ◽  
Calcite Cement

U–Pb ages have been measured on secondary dolomite and silica cements in Cambrian sandstone at the base of an 840 m thick sub-horizontally bedded sedimentary sequence beneath the Bruce nuclear site in southern Ontario to document the history of fluid movement. Results show an average U–Pb age of 320 ± 10 Ma. The initial common Pb end member is slightly, but distinctly, enriched in 206Pb compared with that in older and younger calcite cements elsewhere within the sedimentary section. Combined with previous hydro-geochemical and fluid inclusion studies of the same rocks, the age is interpreted to record episodic migration of a saturated hydrothermal brine. Previously dated calcite cement in sub-horizontal fractures about 500 m higher in the stratigraphic section near the base of the Silurian sequence records similar U–Pb ages of 318 ± 10 Ma by laser ablation inductively coupled plasma mass spectrometry and 313 ± 1 Ma by isotope dilution thermal ionization mass spectrometry. We suggest that the subhorizontal fractures were generated by slumping that resulted from dissolution of underlying evaporite deposits. These ages overlap with the peak of plutonism in the Alleghanian mountains, which were being uplifted contemporaneously 500 km to the southeast. The results suggest the transport of hydrothermal brine from areas of crustal melting through the deep Cambrian sandstone aquifer, while at higher crustal levels meteoric water was also driven over equally large distances by hydraulic gradients from the Alleghanian mountains.

Discussion of the reply by R.L. Romer and U. Kroner on “Geochemical signature of Ordovician Mn-rich sedimentary rocks on the Avalonian shelf” 1Appears in Canadian Journal of Earth Sciences, 49(6): 775–780, 10.1139/e2012-006.

2012 ◽  
Vol 49 (11) ◽  
pp. 1372-1377
Author(s):  
David I. Schofield ◽  
John W.F. Waldron ◽  
Chris E. White ◽  
Sandra M. Barr
Keyword(s):  
Inductively Coupled Plasma ◽  
Sedimentary Rocks ◽  
Sediment Provenance ◽  
Inductively Coupled ◽  
Geochemical Signature ◽  
North Wales ◽  
Plasma Mass Spectrometry ◽  
History Of ◽  
Spectrometry Technique ◽  
Depositional Age

In their article ‘Reply to the discussion by J.W.F. Waldron and C.E. White on “Geochemical signature of Ordovician Mn-rich sedimentary rocks on the Avalonian shelf”’, R.L. Romer and U. Kroner reinterpret geochronological data presented by J.W.F. Waldron, D.I. Schofield, C.E. White, and S.M. Barr to imply an Ordovician, not a Cambrian, depositional age for the succession of the Harlech Dome, North Wales, and Meguma Supergroup, Nova Scotia. However, an extensive history of biostratigraphic and geological survey data refutes this interpretation and shows that the rocks are unequivocally Cambrian. Waldron et al. used the U–Pb zircon laser-ablation – multicollector – inductively coupled plasma – mass spectrometry technique primarily to provide information on sediment provenance and not depositional age. Investigation of anomalously young 206Pb/238U ages showed evidence of Pb loss. These data provide little constraint on depositional age and cannot be used to infer that the Harlech Grits Group is Ordovician.

scholarly journals Evolution of a hydrothermal ore-forming system recorded by sulfide mineral chemistry: a case study from the Plaka Pb–Zn–Ag Deposit, Lavrion, Greece

2021 ◽  
Author(s):  
Max Frenzel ◽  
Panagiotis Voudouris ◽  
Nigel J. Cook ◽  
Cristiana L. Ciobanu ◽  
Sarah Gilbert ◽  
...  
Keyword(s):  
Trace Element ◽  
Inductively Coupled Plasma ◽  
Trace Element Content ◽  
Mineral Chemistry ◽  
Sulfide Mineral ◽  
Fluid Composition ◽  
Inductively Coupled ◽  
Plasma Mass Spectrometry ◽  
Trace Element Contents ◽  
Comparison Of The Results

AbstractLaser ablation-inductively coupled plasma-mass spectrometry and electron-probe microanalysis were used to investigate the trace-element contents of sphalerite, chalcopyrite and pyrite from the Plaka Pb–Zn–Ag deposit. Using petrographic observations, the analytical results could be linked to the temporal evolution of the Plaka ore-forming system. Sphalerite chemistry reliably records the temperature and fS2 evolution of the system, with estimated formation temperatures reproducing the microthermometric results from previous fluid-inclusion studies. Chalcopyrite chemistry also shows systematic variations over time, particularly for Cd, Co, Ge, In, Sn and Zn concentrations. Measurable pyrite was only found in association with early high-temperature mineralisation, and no clear trends could therefore be identified. We note, however, that As and Se contents in pyrite are consistent with formation temperatures estimated from co-existing sphalerite. Statistical analysis of the sphalerite data allowed us to identify the dominant geological controls on its trace-element content. The three investigated factors temperature, fS2, and sample location account for > 80% of the observed variance in Mn, Fe, Co, Ga, Ge, In, Sb and Hg concentrations, and > 60% of the observed variance in Cd and Sn concentrations. Only for Cu and Ag concentrations is the explained variance < 50%. A similarly detailed analysis was not possible for chalcopyrite and pyrite. Nevertheless, comparison of the results for all three investigated minerals indicates that there are some systematic variations across the deposit which may be explained by local differences in fluid composition.

Detrital zircon populations in quartzites of the Krkonoše–Jizera Massif: implications for pre-collisional history of the Saxothuringian Domain in the Bohemian Massif

2011 ◽  
Vol 149 (3) ◽  
pp. 443-458 ◽  
Author(s):  
ELIŠKA ŽÁČKOVÁ ◽  
JIŘÍ KONOPÁSEK ◽  
JAN KOŠLER ◽  
PETR JEŘÁBEK
Keyword(s):  
Detrital Zircon ◽  
Inductively Coupled Plasma ◽  
Detrital Zircons ◽  
Passive Margin ◽  
Inductively Coupled ◽  
Northwestern Margin ◽  
Plasma Mass Spectrometry ◽  
History Of ◽  
Early Palaeozoic ◽  
Ordovician Granitoids

AbstractAge spectra of detrital zircons from metamorphosed quartzites of the Krkonoše–Jizera Massif in the northeastern part of the Saxothuringian Domain were obtained by U–Pb laser ablation inductively coupled plasma mass spectrometry dating. The zircon ages cluster in the intervals of 450–530 Ma and 550–670 Ma, and show individual data between 1.6 and 3.1 Ga. Zircons in the analysed samples are predominantly of Cambrian–Ordovician and Neoproterozoic age, and the marked peak at c. 525–500 Ma suggests a late Cambrian maximum age for the sedimentary protolith. Detritus of the quartzites probably originated from the erosion of Cambrian–Ordovician granitoids and their Neoproterozoic (meta)sedimentary or magmatic country rocks. The lack of Neoproterozoic (meta)sedimentary rocks in the central and eastern part of the Krkonoše–Jizera Massif suggests that the country rocks to voluminous Cambrian–Ordovician magmatic bodies were largely eroded during the formation of early Palaeozoic rift basins along the southeast passive margin of the Saxothuringian Domain. The detrital zircon age spectra confirm the previous interpretation that the exposed basement, dominated by Neoproterozoic to Cambrian–Ordovician granitoids, was overthrust during Devonian–Carboniferous subduction–collision processes by nappes composed of metamorphosed equivalents of the uppermost Cambrian–Devonian passive margin sedimentary formations. Only a negligible number of Mesoproterozoic ages, typically from the Grenvillian event, supports the interpretation that the Saxothuringian Neoproterozoic basement has an affinity to the West African Craton of the northwestern margin of Gondwana.

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