LA-ICP-MS U-(Th-)Pb Network roles, goals and objectives

A LA-ICP-MS U-Th-Pb Network, recognised as a Special Interest Group of the International Association of Geoanalysts (IAG), has been established to define and promote best practice in laser ablation U-(Th-)Pb Geochronology. The role, goal and objectives of the Network are defined below:

Name

LA-ICP-MS U-(Th-)Pb Network (formerly the Working Group on LA-ICP-MS U-(Th-)Pb Geochronology).

Role

We are a network of active researchers co-ordinating investigations into salient issues in the acquisition, handling and interpretation of LA-ICP-MS U-(Th-)Pb data, drawing on the expertise from within and outside of the U-Pb community as required, as well as providing a support structure for relevant investigations performed by other groups/researchers.

Raison d'etre – To define and promote current best practice in acquiring, processing and interpreting laser ablation ICP-MS U-(Th-)Pb geochronology data.

For published ages to be of maximum value to the field geologist there is a responsibility on the part of data producers for their data to be robust and the interpretations based on these data to be reliable, with appropriate levels of uncertainty on both data and age interpretations. We therefore intend to develop guidelines to help new and existing users acquire, process and interpret their data in a manner commensurate with a robust and reliable geological interpretation.

Although focussing on the LA community at present, many of the issues and problems are generic to the broader U-(Th-)Pb community (i.e., including SIMS and TIMS). Cross-discipline liaison will form an essential part of the Network’s actions since many of the required skills and existing concerted efforts on some of the issues can be found in these communities.

Goal - To ensure that published LA-ICP-MS U-(Th-)Pb data are robust and have an appropriate assessment of uncertainty (including age uncertainty on the result) for the field geologist to use with confidence.

Objectives

  • To highlight what can and cannot be resolved in the interpretation of LA U-(Th-)Pb data
  • To determine the limiting factors in the data
  • To recommend ways to improve the quality and consistency of published LA U-(Th-)Pb data and their interpretation, and to illustrate the steps that are required to achieve this consistency
  • To encourage regular participation by the most active labs in ILC exercises
  • To prepare guidelines for best practice in acquiring, handling, reporting and interpreting data
  • To organise workshops to consult and gain input
  • To establish cross-discipline (ICP-MS/SIMS/TIMS) collaboration on common problems
  • To improve the robustness of data processing and interpretation of published data between labs as measured using ILC exercises
  • To organise Shortcourses to disseminate the results and train practitioners

Initial Tasks

  • Draw up guidelines for reporting of data based on discussions held at the workshops. Guidelines to be output as a short paper and/or via the web.
  • Initiate and support the production of a series of papers
  • Co-ordinate a small study using synthetic U-Pb solutions to investigate the limiting uncertainties in U-(Th-)Pb ICP-MS analysis (i.e. without laser ablation) and to highlight specific aspects of concordant and discordant U-Pb data in order to investigate the resolution achievable with ICP-MS.
  • Instigate an ILC program amongst the LA U-(Th-)Pb community utilising the protocols and systems already in place in the IAG
  • Create links and work with the SIMS and TIMS communities on common issues of mutual importance
  • Promote the existence of the Network and the uptake of its principles by the U-(Th-)Pb community, wherever and whenever possible

Co-ordinators - Matt Horstwood (Lead co-ordinator), Jan Kosler, George Gehrels, Simon Jackson, Norman Pearson, Paul Sylvester

Community partner representatives – Noah McLean (Uncertainties), Dan Condon (TIMS), Keith Sircombe (SIMS), Jim Bowring (Cyber-infrastructure)

Contributors - all interested researchers

We look forward to liaising with you all and with our SIMS and TIMS colleagues, on this initiative which we feel is of paramount importance for our science at this time.

Very best regards

Matt Horstwood
Jan Kosler
George Gehrels
Simon Jackson
Norman Pearson
Paul Sylvester

(Co-ordinators, LA-ICP-MS U-(Th-)Pb Network)