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Methods and applications of geochronology /

Methods and Applications of Geochronology provides a comprehensive, practical guide to the rapidly developing field of geochronology.Chapters are written by leading experts in their specific field of geochronology and discuss practical information and 'rules of thumb' for establishing labo...

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Bibliographic Details
Corporate Author: ScienceDirect (Online service)
Other Authors: Shellnutt, J. Gregory, Denyszyn, Steven W. (Editor), Suga, Kenshi (Editor)
Format: eBook
Language:English
Published: Amsterdam, Netherlands : Elsevier, 2024.
Subjects:
Geological time.
Géochronologie.
Electronic books.
Online Access:Connect to the full text of this electronic book
Table of Contents:
  • Front Cover
  • Methods and Applications of Geochronology
  • Methods and Applications of Geochronology
  • Copyright
  • Dedication
  • Contents
  • Contributors
  • Preface
  • 1
  • Introduction to methods and applications of geochronology: A perspective on geological time
  • 1. Introduction
  • 2. Awareness and observation of geological and biological time: pre-20th century
  • 2.1 Quod tempus est?
  • 2.2 The journey into deep time
  • 2.3 Uniformitarianism and the geological timescale
  • 3. In search of an absolute time
  • 3.1 The modern approach
  • References
  • 2
  • High-precision CA-ID-TIMS U-Pb geochronology of zircon: Materials, methods, and interpretations
  • 1. Introduction
  • 2. Establishing a U-Pb dating infrastructure and installing best practices
  • 2.1 Sample preparation and mineral separation
  • 2.1.1 Crushing
  • 2.1.2 Shaking table separation
  • 2.1.3 Magnetic separation
  • 2.1.4 Density separation
  • 2.1.5 Optical separation and selection
  • 2.2 Sample imaging (and in situ analyses) (Fig. 2.1B)
  • 2.3 Chemical abrasion (Fig. 2.1C)
  • 2.4 Low-level Pb, clean air chemistry
  • 2.4.1 Low procedural Pb blank
  • 2.4.2 Isotopic tracers ("spikes")
  • 2.4.3 Clean air environment
  • 2.4.4 Clean materials
  • 2.4.5 Elemental separation workflow
  • 2.5 Mass spectrometry (Fig. 2.1E)
  • 2.6 Data treatment
  • 3. Quality assessment
  • 3.1 Precision
  • 3.1.1 Analytical variation during the acquisition of mass spectrometry data
  • 3.1.2 Fractionation of measured Pb or U isotope ratios
  • 3.1.3 Correction for common Pb in analysis
  • 3.2 Accuracy
  • 3.3 Repeatability
  • 3.4 Reproducibility
  • 4. Interpretation of high-precision U-Pb zircon dates
  • 4.1 Which geological event or moment is zircon dating?
  • 4.2 Do all zircon crystals in an igneous rock sample reproduce the same age?
  • 4.3 Reasons of age scatter
  • 4.3.1 Protracted growth.
  • 4.3 Analytical setup
  • 4.3.1 Reaction gasses and ICP-MS/MS tuning
  • 4.3.2 Isotopic analyses
  • 4.4 Reference materials
  • 4.5 Calculations
  • 4.5.1 Isotopic ratios
  • 4.5.2 Error propagation
  • 5. Re-Os geochronology
  • 5.1 Overview
  • 5.2 Minerals and applications
  • 5.2.1 Molybdenite
  • 5.2.2 Sulfides
  • 5.3 Analytical setup
  • 5.3.1 Reaction gasses and ICP-MS/MS tuning
  • 5.3.2 Isotopic analyses
  • 5.4 Reference materials
  • 5.5 Calculations
  • 5.5.1 Isotopic ratios
  • 6. Future directions
  • 6.1 Reference materials
  • 6.2 Data processing software
  • 6.3 Expanding the technique
  • Appendix 1. Instrument analytical conditions
  • Acknowledgments
  • References
  • 9
  • The complexities in interpreting Argon isotopes: Chock-full of components
  • 1. Introduction and scope
  • 2. Brief introduction to 40K/40Ar and 40Ar/39Ar dating
  • 2.1 General overview of the method and techniques
  • 2.1.1 40K/40Ar dating method
  • 2.1.2 40Ar/39Ar dating method
  • 2.1.3 38Ar/37Ar CRE age
  • 2.2 Monitors and nuclear reactions
  • 2.2.1 Neutron interference reactions on Ca, K, and halogens
  • 2.3 Extraction techniques: advantages and disadvantages
  • 2.3.1 Stepped heating
  • 2.3.2 Laser ablation
  • 2.3.3 Crushing
  • 3. Different Ar components and their sources
  • 3.1 Natural and neutron-produced Ar isotope compositions
  • 3.2 Argon components
  • 3.3 Modification by metamorphism and impacts
  • 4. Data presentation
  • 4.1 Age spectrum
  • 4.2 Three-isotope correlation diagrams: 39Ar/36Ar versus 40Ar/36Ar or 39Ar/40Ar versus 36Ar/40Ar
  • 5. 40K/40Ar data correction and interpretation
  • 5.1 40K/40Ar dating of young volcanic rocks and minerals: inherited Ar in feldspar concentrated in melt inclusions
  • 5.2 Identifying inherited Ar in whole rock based on magmatic/crustal He trapped in fluid/melt inclusions.