A zircon classification scheme for sedimentary provenance analysis using radiation damage

Abstract

<p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en">Detrital single‐grain zircon U–Pb geochronology is a powerful tool for provenance studies if information on the source rocks is available. This paper proposes a new source‐rock classification tool that uses the degree of annealing of radiation damage in detrital zircon; the annealing is expressed by the relationship between the width (full‐width at half‐maximum; FWHM) of the <italic toggle="no">v</italic>₃[SiO₄] Raman band at ~1008 cm⁻¹ and the calculated α‐dose. The host rocks of the zircons are classified into three types according to their emplacement process and/or thermal history: volcanic and rapidly cooled plutonic and high‐grade metamorphic rocks (type 1); rocks with hydrothermal zircons (type 2); slowly cooled igneous and metamorphic rocks (type 3). We construct a naive Bayes prediction model by training it with a collection of zircons of known types. The unknown zircons are assigned a probability of derivation from a specific host‐rock type. This classification scheme is best used as an accessory tool in provenance studies that apply detrital zircon U–Pb geochronology.</p>

<p xmlns:mml="http://www.w3.org/1998/Math/MathML" xml:lang="en">Zircons are classified into three types based on annealing state revealed by Raman analysis and calculated α‐dose. This classification can be used to distinguish zircon in provenance study.<boxed-text position="anchor" content-type="graphic" id="gj4751-blkfxd-0001" xml:lang="en"> <graphic position="anchor" id="jats-graphic-1" xlink:href="urn:x-wiley:00721050:media:gj4751:gj4751-toc-0001"> </graphic> </boxed-text></p>