학술논문
Duluth Complex apatites: Age reference material for LA–ICP–MS‐based fission‐track dating.
Document Type
Article
Source
Subject
*FISSION track dating
*APATITE
*REFERENCE sources
*DETERIORATION of materials
*LASER ablation inductively coupled plasma mass spectrometry
*ANALYTICAL chemistry
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Language
ISSN
0954-4879
Abstract
Anorthositic series apatites of the Duluth Complex, Minnesota, USA, have high spontaneous fission‐track densities of up to ~107 cm–2 and a homogeneous age of ~900 Ma, allowing high‐precision fission‐track dating based on LA–ICP–MS U analysis. Absolute fission‐track dating, track‐length measurement and chemical composition analysis were performed to evaluate a cooling history, which is essential for age reference materials. Preliminary inverse modelling for a sample with a shortened track‐length distribution yielded a monotonic cooling history from ~100°C at 925 Ma. The apatites incur an over‐etching problem when employing the commonly used etching protocol involving 5.5 M HNO3. [ABSTRACT FROM AUTHOR]