Embedded Files
ChemChron — chemical and isotopic ages and mineral chemistry of U–Th-bearing minerals
ChemChron — chemical and isotopic ages and mineral chemistry of U–Th-bearing minerals
ChemChron is a free desktop application for calculating Th–U–Pb chemical ages from electron microprobe (EPMA) data and isotopic U–Th–Pb ages from LA-ICP-MS data on monazite, xenotime, zircon and other U–Th-bearing minerals, together with their mineral chemistry. It covers the workflow from raw analyses to publication-ready results:
Chemical ages: import of EPMA exports (from file or by copy and paste), automatic mineral classification and structural formulae, isochron and weighted-mean ages with full error propagation and optional outlier rejection.
Isotopic ages: import of reduced LA-ICP-MS U–Pb ratios; ²⁰⁶Pb/²³⁸U, ²⁰⁷Pb/²³⁵U, ²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²³²Th ages; discordance filtering; Wetherill and Tera–Wasserburg concordia plots, concordia ages, discordia intercepts and weighted means.
Uncertainties: a two-component model. A random excess per analysis is estimated per measurement session from the reference materials. A systematic term comes from long-term reproducibility, tracked separately for chemical and isotopic data.
Mineral chemistry: import of trace-element data (e.g. LA-ICP-MS REE), chondrite-normalised REE diagrams, ternary and binary composition plots.
Settings and output: editable reference materials and decay constants; export of tables to Excel, LibreOffice and CSV, and of plots at journal sizes as PDF, SVG, EPS, PNG or TIFF.
ChemChron runs natively on Windows, macOS and Linux (current version 1.1.2). It is still evolving, so I’d be grateful for feedback, bug reports or suggestions from anyone who tries it.
Google Sites
Report abuse