文章基本信息

标题：Assessing volcanic origins within detrital zircon populations – A case study from the Mesozoic non-volcanic margin of southern Australia
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作者：Milo Barham ; Christopher L. Kirkland ; Martin Danišík 等
期刊名称：Geoscience Frontiers
印刷版ISSN：1674-9871
出版年度：2019
卷号：10
期号：4
页码：1371-1381
DOI：10.1016/j.gsf.2019.01.003
语种：English
出版社：Elsevier
摘要：AbstractDetrital zircon U/Pb geochronology is a common tool used to resolve stratigraphic questions, inform basin evolution and constrain regional geological histories. In favourable circumstances, detrital zircon populations can contain a concomitant volcanic contribution that provides constraints on the age of deposition. However, for non-volcanic settings, proving isolated detrital zircon grains are from contemporaneous and potentially remote volcanism is challenging. Here we use same grain (U–Th)/He thermochronology coupled with U/Pb geochronology to identify detrital zircon grains of contemporary volcanic origin. (U–Th)/He ages from Cretaceous zircon grains in southern Australia define a single population with a weighted mean age of 104 ± 6.1 Ma, indistinguishable from zircon U/Pb geochronology and palynology (∼104.0–107.5 Ma). Detrital zircon trace-element geochemistry is consistent with a continental signature for parent rocks and coupled with detrital grain ages, supports derivation from a >2000 km distant early- to mid-Cretaceous Whitsunday Volcanic Province in eastern Australia. Thus, integration of biostratigraphy, single-grain zircon double-dating (geochronology and thermochronology) and grain geochemistry enhances fingerprinting of zircon source region and transport history. A distal volcanic source and rapid continental-scale transport to southern Australia is supported here.Graphical abstractDisplay OmittedHighlights•Integrated thermochronology-geochronology-geochemistry resolves detrital zircon histories.•Coupled (U-Th)/He and U-Pb chronology can help distinguish volcanic zircon components.•Cretaceous zircons on the Madura Shelf rapidly deposited after volcanic genesis.•Madura Shelf zircon trace-elements support an origin in eastern Australian volcanics.•No evidence for Mesozoic volcanism in Bight Basin, southern Australia.
关键词：KeywordsenProvenanceGrain historyThermochronologyGeochronologySource to sinkTrace-elements