Results 51 to 60 of about 516 (186)

An ion microprobe U-Th-Pb study of zircon xenocrysts from the Lahtojoki kimberlite pipe, eastern Finland [PDF]

Bulletin of the Geological Society of Finland, 2001
Eleven relatively large (diameter 1–2 mm) zircon grains extracted from the Lahtojoki kimberlite pipe (Eastern Finland Kimberlite Province) have been analysed by the ion microprobe NORDSIM for their U- and Pb- isotopic composition.
P. Peltonen, I. Mänttäri
doaj   +1 more source

Automated particle analysis of D.B. Cooper's tie

Journal of Forensic Sciences, EarlyView.
Abstract Automated particle analysis (APA) using scanning electron microscopy (SEM) and energy‐dispersive x‐ray spectrometry (EDS) is a well‐known method in forensics, especially as it is applied to gunshot residue analysis. Here we describe the analysis of particles lifted from D.B. Cooper's tie, which was left on the hijacked plane in 1971.
Thomas G. Kaye, Kent L. Rhodes
wiley   +1 more source

The Material Basis of 18th‐Century Meissen Porcelain

Archaeometry, EarlyView.
ABSTRACT In the summer of 1708, the quest for making hard‐paste porcelain from Saxonian clay and other mineral resources succeeded. This was achieved by applying as its essential ingredient newly discovered pure kaolin from Heidelsberg near Aue, western Saxon Ore Mountains.
Robert B. Heimann
wiley   +1 more source

ReMoDe – Recursive modality detection in distributions of ordinal data

British Journal of Mathematical and Statistical Psychology, EarlyView.
Abstract The detection of the number of modes in distributions of ordinal data is relevant for applied researchers across disciplines, from uncovering polarization to detecting incidence groups in clinical symptom scales. Yet, established modality detection methods are either purely descriptive or not developed for ordinal data.
Madlen Hoffstadt, Lourens Waldorp, Javier Garcia‐Bernardo, Han van der Maas   +3 more
wiley   +1 more source

Resolving Micrometre‐Scale Zircon Growth in Silicic Systems by 7 μm LA‐MC‐ICP‐MS U‐Pb Dating: Linking Petrology and Geochronology in Silicic Volcanic and Granitic Rocks from Victoria, Australia

Geostandards and Geoanalytical Research, EarlyView.
Key Points 7 μm spot‐diameter LA‐MC‐ICP‐MS analyses yield accurate zircon U‐Pb ages. 1013 Ω amplifier resistors improve low‐signal Pb measurements. Saturn correction protocols minimise down‐hole fractionation effects. We present a systematic evaluation of high spatial‐resolution zircon U‐Pb dating using a Thermo Scientific Neoma multi‐collector ICP‐MS ...
Cristiano Lana, John D. Clemens
wiley   +1 more source

(Ultra)high‐Pressure Metamorphism in Sedimentary Versus Basaltic Rocks: Insights From a Variscan Mélange in the South Carpathians

Journal of Metamorphic Geology, EarlyView.
ABSTRACT Reconstructing the pressure–temperature–time (P–T–t) evolution of (ultra)high‐pressure rocks is essential for constraining subduction and collisional dynamics. Subduction zones are often investigated using basic eclogites, whereas nonbasic high‐pressure rocks remain comparatively understudied, potentially hindering a comprehensive ...
Otavio S. G. Silva, Bruno V. Ribeiro, Gavril Săbău, Fabricio Caxito, Paulo A. de Paiva‐Silva, Pierre Lanari, George Luvizotto, Mahyra Tedeschi   +7 more
wiley   +1 more source

Feldspar Albitization With Implications for Reservoir Quality Evolution of Eocene Turbidite Sandstones in Offshore Espírito Santo Basin, Eastern Brazil

Journal of Petroleum Geology, EarlyView.
ABSTRACT The diagenetic albitization of plagioclase and K‐feldspar grains is a transformative process that significantly alters sandstone's detrital composition and formation water chemistry, impacting reservoir quality. In this study, Eocene turbidite sandstones from the offshore Espírito Santo Basin, Brazil, were investigated to elucidate the role of
Eveline E. Zambonato, Luiz F. De Ros, Howri Mansurbeg   +2 more
wiley   +1 more source

Early archean inheritance in zircon from Mesozoic dalongshan granitoids in the Yangtze Foldbelt of Southeast China.

GEOCHEMICAL JOURNAL, 1990
Zircon U-Pb isotopic data on the early Cretaceous Dalongshan granitoids in the Yangtze Foldbelt of Southeast China provides evidence for the incorporation of old Archean crustal material. The age of inherited radiogenic lead is determined by the three-dimensional U-Pb discordia plane method to be about 3330±180 Ma, indicating that the early Archean ...
Hong, Zhang, Yong-Fei, Zheng, Mao-Gong, Zheng, Jun-Long, Yeng   +3 more
openaire   +2 more sources

The Ames impact structure, Oklahoma: New radioisotopic constraints and implications for North American impact chronology

Meteoritics &Planetary Science, EarlyView.
Abstract The Ames impact structure (Oklahoma) is thought to have formed during the Ordovician Meteor Event, based on conodont biostratigraphy of its crater fill. Here, U–Pb zircon dates from its impact‐melt portion, conducted using secondary ion mass spectrometry and laser ablation–inductively coupled plasma–mass spectrometry (n = 37 spots), yield a ...
Elizabeth J. Catlos, Andrew F. Parisi, Michael E. Brookfield, Timmons Erickson, Sean P.S. Gulick, Axel K. Schmitt, Daniel F. Stockli, Daniel P. Miggins, Ben Ruchte, Mark Cloos   +9 more
wiley   +1 more source

Data analysis of the U–Pb geochronology and Lu–Hf system in zircon and whole-rock Sr, Sm–Nd and Pb isotopic systems for the granitoids of Thailand

Data in Brief, 2018
This data article provides zircon U–Pb and Lu–Hf isotopic information along with whole-rock Sm–Nd, Sr and Pb isotopic geochemistry from granitoids in Thailand.
Romana E.C. Dew, Simon Nachtergaele, Alan S. Collins, Stijn Glorie, John Foden, Johan De Grave, Morgan L. Blades, Christopher K. Morley, Noreen J. Evans, Brandon L. Alessio, Pitsanupong Kanjanapayont, Rosalind King, Punya Charusiri   +12 more
doaj   +1 more source