Topic
Sensitive high-resolution ion microprobe
About: Sensitive high-resolution ion microprobe is a research topic. Over the lifetime, 134 publications have been published within this topic receiving 15103 citations. The topic is also known as: sensitive high mass-resolution ion microprobe.
Papers published on a yearly basis
Papers
TL;DR: The importance of zircon in crustal evolution studies is underscored by its predominant use in U-Th-Pb geochronology and investigations of the temporal evolution of both the crust and lithospheric mantle as discussed by the authors.
Abstract: Zircon is the main mineral in the majority of igneous and metamorphic rocks with Zr as an essential structural constituent. It is a host for significant fractions of the whole-rock abundance of U, Th, Hf, and the REE (Sawka 1988, Bea 1996, O’Hara et al. 2001). These elements are important geochemically as process indicators or parent isotopes for age determination. The importance of zircon in crustal evolution studies is underscored by its predominant use in U-Th-Pb geochronology and investigations of the temporal evolution of both the crust and lithospheric mantle. In the past decade an increasing interest in the composition of zircon, trace-elements in particular, has been motivated by the effort to better constrain in situ microprobe-acquired isotopic ages. Electron-beam compositional imaging and isotope-ratio measurement by in situ beam techniques—and the micrometer-scale spatial resolution that is possible—has revealed in many cases that single zircon crystals contain a record of multiple geologic events. Such events can either be zircon-consuming, alteration, or zircon-forming and may be separated in time by millions or billions of years. In many cases, calculated zircon isotopic ages do not coincide with ages of geologic events determined from other minerals or from whole-rock analysis. To interpret the geologic validity and significance of multiple ages, and ages unsupported by independent analysis of other isotopic systems, has been the impetus for most past investigations of zircon composition. Some recent compositional investigations of zircon have not been directly related to geochronology, but to the ability of zircon to influence or record petrogenetic processes in igneous and metamorphic systems.
Sedimentary rocks may also contain a significant fraction of zircon. Although authigenic zircon has been reported (Saxena 1966, Baruah et al. 1995, Hower et al. 1999), it appears to be very rare and may in fact be related to …
4,530 citations
1 Jan 1997
2,424 citations
TL;DR: The TEMORA 1 zircon standard derives from the Middledale Gabbroic Diorite, a high-level mafic stock within the Palaeozoic Lachlan Orogen of eastern Australia as mentioned in this paper.
2,335 citations
TL;DR: In this paper, the age of four zircons from thin-sections of one highland breccia, 73217, using the recently constructed ion microprobe SHRIMP was determined.
Abstract: U-Pb age determinations on four lunar zircons from existing thin-sections of one highland breccia, 73217, using the recently constructed ion microprobe SHRIMP, are reported. The analytical reproducibility of SHRIMP is demonstrated, and procedures for measuring Pb/U, Th/U, and corecting for initial Pb are explained. Electron microprobe analyses for the zircons are alsoar reported. The results show that the four zircons survived the lunar cataclysm without any identifiable effects on their U-Pb systematics. All four indicate a single age of 4356 +23 or -14 m.y. The zircons have experienced small variable amounts of Pb loss since crystallization, from almost zero up to about 10 percent. If this occurred during one later event, then age of the latter is between 1100 and 2300 m.y.
1,387 citations
TL;DR: In this article, an ion microprobe U-Th-Pb analysis of residual cores and metamorphic mantles of zircons from three high grade paragneisses from the Seve Nappe Complex, north-western Sweden, showed that the sediments comprising the protolith of the gneisses over a distance of 250 km were probably derived from similarly-aged source terranes.
Abstract: Ion microprobe U-Th-Pb analyses of residual cores and metamorphic mantles of zircons from three high grade paragneisses from the Seve Nappe Complex, north-western Sweden, show that: 1) The sediments comprising the protolith of the Seve Nappes gneisses over a distance of 250 km were probably derived from similarly-aged source terranes. 2) Those source terranes were dominated by rocks with ages in the range 1400 to 1730 Ma, with minor components at least as young as 1000 Ma. The oldest component identified is 1730±12 Ma old. 3) Those rocks had U and Th contents normal for felsic igneous rocks. 4) The gneiss protolith was metamorphosed to granulite grade during the Caledonian. There is evidence to suggest that the peak of metamorphism may not have been synchronous throughout the Nappes. 5) The metamorphism probably included a reduction of about a factor of ten in the gneisses' Th/U.
940 citations
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Performance Metrics
| Year | Papers |
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| 2022 | 1 |
| 2021 | 2 |
| 2020 | 2 |
| 2019 | 2 |
| 2018 | 2 |
| 2017 | 3 |