Standardizing Re–Os geochronology: A new molybdenite Reference Material (Henderson, USA) and the stoichiometry of Os salts

Markey, Richard J.; Stein, Holly J.; Hannah, Judith L.; Zimmerman, A.; Selby, David; Creaser, Robert A.

doi:10.1016/j.chemgeo.2007.06.002

Cited by 125 publications

(71 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Granite sample (AF33-10), and to avoid losing molybdenite during crushing, the mineral separate was achieved using a room temperature HF dissolution of quartz (Smoliar et al, 1996) of molybdenite reference materials (NISTRM8599 = 27.6 ± 0.1 and 27.6 ± 0.1 Ma; HLP-5 = 220.0 ± 0.9 Ma), which are in good agreement with their accepted values determined at other laboratories and those previously reported at Durham University (Markey et al, 1998(Markey et al, , 2007Porter & Selby, 2010).…”

Section: Fluid Inclusion Types Gruide Granitesupporting

confidence: 76%

Silurian–Devonian magmatism, mineralization, regional exhumation and brittle strike-slip deformation along the Loch Shin Line, NW Scotland

Holdsworth

Dempsey

Selby

et al. 2015

JGS

View full text Add to dashboard Cite

The Loch Shin Line is a geological–geophysical lineament associated with a zone of mantle-derived appinites, granites and strike-slip faulting that runs NW–SE across the Moine Nappe, northern Scotland. U–Pb zircon and Re–Os molybdenite dating of the Loch Shin and Grudie plutons, which lie immediately SW of the NW–SE Loch Shin–Strath Fleet fault system, yield c . 427–430 Ma ages that overlap within error. They also coincide with previously obtained U–Pb zircon ages for the Rogart pluton, which lies along-strike to the SE. Field and microstructural observations confirm the similarity and contemporaneous nature of the plutons and associated sulphide mineralization. Fluid inclusion analyses place further constraints on the P – T – X conditions during regional late Caledonian exhumation of the Moine Nappe. Synchronous to slightly younger brittle dextral strike-slip faulting along the WNW–ESE Loch Shin–Strath Fleet Fault System was probably antithetic to sinistral movements along the nearby Great Glen Fault Zone. Our findings support the hypothesis that the Loch Shin Line acted as a deep crustal channelway controlling the ascent and emplacement of Silurian magmas into the overlying Moine Nappe. We propose that this deep structure corresponds to the southeastern continuation of the Precambrian-age Laxford Front shear zone in the buried Lewisian autochthon. Supplementary Material: Field photographs, photomicrographs and fluid inclusion information are available at http://www.geolsoc.org.uk/SUP18859 .

show abstract

Section: Fluid Inclusion Types Gruide Granitesupporting

confidence: 76%

Silurian–Devonian magmatism, mineralization, regional exhumation and brittle strike-slip deformation along the Loch Shin Line, NW Scotland

Holdsworth

Dempsey

Selby

et al. 2015

JGS

View full text Add to dashboard Cite

show abstract

“…Methods used to analyze the molybdenite are described in detail by Selby and Creaser (2004) and Markey et al (2007) . Whole-rock K-Ar dating of two samples from biotiterich, hydrothermally altered granite porphyry (Granite II) yielded much younger ages of 339 ± 10 and 334 ± 7 Ma (Kooiman et al 1986).…”

Section: Analytical Proceduresmentioning

confidence: 99%

Re-Os geochronological constraints on the mineralizing events within the Mount Pleasant Caldera: implications for the timing of sub-volcanic magmatism

Thorne¹,

Fyffe²,

Creaser

2013

atgeol

View full text Add to dashboard Cite

The Mount Pleasant granite-related polymetallic deposit, located on the southwestern margin of the Late Devonian to Early Carboniferous Mount Pleasant Caldera Complex in southwestern New Brunswick, contains a significant resource of tin, tungsten, molybdenum, zinc, indium, and bismuth. The Caldera Complex comprises Intracaldera, Exocaldera, and Late Caldera-Fill sequences and associated subvolcanic granitic rocks. Three granitic phases of the Mount Pleasant Granitic Suite (Granite I, II, and III) are recognized in the vicinity of the Mount Pleasant deposit and are interpreted to be fractionates of the more regionally exposed McDougall Brook Granitic Suite. Granite I and Granite II are associated with tungsten-molybdenum-bismuth, and tin-zinc-indium mineralization, respectively. Despite extensive research within the Caldera Complex, the exact age of mineralization at Mount Pleasant has never been firmly established. An inferred age of 363 ± 2 Ma was based on the proposed synchronicity of the U-Pb dated Bailey Rock Rhyolite of the Exocaldera Sequence with that of the undated McDougall Brook Granitic Suite, which intrudes the Intracaldera Sequence. Here, we present Re-Os dating of two molybdenite samples associated with the tungsten mineralization related to Granite I at the Fire Tower Zone, that constrain the initial onset of mineralization at Mount Pleasant to be between 369.7±1.6 Ma and 370.1±1.7 Ma. The new Re-Os ages clearly indicate that the McDougall Brook Granitic Suite, which pre-dates mineralization, must be at least seven million years older than the Bailey Rock Rhyolite, whose type-section is located within the Exocaldera Sequence. A re-examination of the gradational relationship between the McDougall Brook Granitic Suite and purported rocks of Bailey Rock Rhyolite within the Intracaldera Sequence revealed that the latter should instead be assigned to the Seelys Formation. Thus, deposition of the polymetallic mineralization likely took place contemporaneously with caldera collapse and an early phase of resurgent doming in response to degassing of the magma chamber rather than being coincident with erosion of the volcanic edifice as inferred from previous modeling of the eruptive history at Mount Pleasant.

show abstract

“…In order to avoid anomalous results produced by the sampling of multiple generations of molybdenite, relatively small aliquots of molybdenite with weights of approximately 1.2 mg were separated. These were accurately weighed and dissolved together with a known amount of "mixed- Re; Markey et al, 2007) in a thick-walled Carius tube. Os and Re were separated using a combination of solvent extraction, microdistillation and anion chromatographic methods and analyzed by N-TIMS using a Thermo Triton mass spectrometer and Faraday Collectors.…”

Section: Geochronologymentioning

confidence: 99%

The Distribution and Timing of Molybdenite Mineralization at the El Teniente Cu-Mo Porphyry Deposit, Chile

et al. 2015

View full text Add to dashboard Cite

Standardizing Re–Os geochronology: A new molybdenite Reference Material (Henderson, USA) and the stoichiometry of Os salts

Cited by 125 publications

References 26 publications

Silurian–Devonian magmatism, mineralization, regional exhumation and brittle strike-slip deformation along the Loch Shin Line, NW Scotland

Silurian–Devonian magmatism, mineralization, regional exhumation and brittle strike-slip deformation along the Loch Shin Line, NW Scotland

Re-Os geochronological constraints on the mineralizing events within the Mount Pleasant Caldera: implications for the timing of sub-volcanic magmatism

The Distribution and Timing of Molybdenite Mineralization at the El Teniente Cu-Mo Porphyry Deposit, Chile

Contact Info

Product

Resources

About