In-situ Rb-Sr dating of celadonite from altered upper oceanic crust using laser ablation ICP-MS/MS

Testing Nano‐Powder and Fused‐Glass Mineral Reference Materials for In SituRb‐Sr Dating of Glauconite, Phlogopite, Biotite and Feldspar via LA‐ICP‐MS/MS

“…The 87 Rb/ 86 Sr and 87 Sr/ 86 Sr ratios were processed using the Iolite v4 software (Paton et al 2011), coupled with a customised data reduction scheme for the Rb-Sr isotopic analysis available from https://forum.iolite.xyz/d/148-new-rbsr-drs (Redaa et al 2021). Rb-Sr data processing is described in detail in previous publications (Hogmalm et al 2017, Laureijs et al 2021. Rb-Sr isochrons and ages were calculated using the IsoplotR software (Vermeesch 2018).…”

“…However, the general lack of well-characterised and matrix-matched RMs for in situ Rb-Sr measurement remains one of the main challenges for this dating technique as only a limited number of suitable RMs are available to calibrate in situ 87 Rb/ 86 Sr and 87 Sr/ 86 Sr data. Specifically, most recent in situ Rb-Sr dating studies have relied on a combination of the following RMs, including: the glasses NIST SRM 610, BCR-2G and BHVO-2G, and a single available nanopowder (NP) phlogopite RM (Mica-Mg-NP) (Table 1) (Zack and Hogmalm 2016, S ßeng€ un et al 2019, Armistead et al 2020, Gorojovsky and Alard 2020, Li et al 2020, Olierook et al 2020, Tillberg et al 2020, Laureijs et al 2021). In addition, some MPI-DING glasses were used as RMs for in situ dating, including ATHO-G (rhyolite), T1-G (quartzdiorite) and StHs6/80-G (andesite) (Laureijs et al 2021), and their 87 Sr/ 86 Sr recommended values are listed in Table 1.…”

“…The current approach for in situ Rb-Sr dating, designed to overcome these matrix effects, relies primarily on the analysis of additional RMs (i.e., well-characterised natural minerals) with previously determined ages which can be used to monitor the overall quality and repeatability of in situ Rb-Sr data (Armistead et al 2020, Li et al 2020, Olierook et al 2020, Bevan et al 2021, Laureijs et al 2021. Such monitoring of data quality, along with the application of secondary calibration when needed, allows in situ Rb-Sr ages to be determined with an accuracy and precision ranging between 1.5% to 3% (Armistead et al 2020, Li et al 2020, Olierook et al 2020, Bevan et al 2021, Subarkah et al 2021).…”

Short communication: On the potential use of materials with heterogeneously distributed parent and daughter isotopes as primary standards for non-U–Pb geochronological applications of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)

“…The use of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for in situ geochronology is growing rapidly, and recent years have seen this technique being applied to many new minerals and isotope systems. Examples include in situ U-Pb dating of apatite (Chew et al, 2014(Chew et al, , 2011, carbonates (Roberts et al, 2017;Li et al, 2014;Guillong et al, 2020) and epidote (Peverelli et al, 2021), Rb-Sr dating of micas (Hogmalm et al, 2017;Zack and Hogmalm, 2016), alkali feldspar (Bevan et al, 2021) and celadonite (Laureijs et al, 2021), Lu-Hf dating of garnet, apatite and xenotime (Simpson et al, 2021), and a new approach to Re-Os dating of molybdenite (Hogmalm et al, 2019). One important challenge associated with this rapid growth is the development of matrixmatched primary standards to correct for elemental fractionation during LA-ICP-MS analysis.…”

Atomic spectrometry update – a review of advances in environmental analysis

“…A nanopowder pellet called mica-Fe was proposed as a secondary RM for Rb-Sr geochronology. In a study of LA-ICP-MS/MS applied to the Rb-Sr dating of celadonite to decipher alteration conditions aer accretion of oceanic crust, methyl uoride was employed 260 as the reaction gas and the 87 Rb/ 86 Sr ratios calibrated using several of the MPI-DING glass RMs. Bevan et al 261 demonstrated the capabilities of a prototype "tribrid" MS system coupled to a UV LA system for in situ Rb-Sr dating.…”