Looking forward: the next generation of tools and techniques

As we have seen in the preceding chapters, although there is only a relatively small number of radioactive decay schemes with half lives appropriate to interrogate the terrestrial geological record, various developments and refinements in both techniques and materials being analysed have driven major conceptual understandings. In part, these advances have come through improvements in instrumentation, but also through recognition of a problem that needed to be solved. Hence it is possible to foresee both a technical progression which is technology and technique based, and an application-driven progression where existing techniques are applied in new and novel ways.

Although not covered to any degree in this book, increasingly the integration of radiogenic and stable isotope studies will yield a combined approach to understanding systems in ways that have not previously been possible. This can be combined with underutilised radioactive decay schemes, depending on the problem to be solved. For example, the 190Pt–186Os decay scheme has not been discussed here as the parent, 190Pt, is present in only very low levels (~0.0014 per cent of all natural Pt) and has an incredibly long half life (~430 Gyr, or 30 times the age of the universe). Hence to date it has really only been investigated in a small number of extraterrestrial and core–mantle interaction settings, yet it may have a small number of niche applications in mineralisation situations where integration of Re–Pt–Os and even stable Os isotopes may offer insights that were previously unobtainable. This example, while technically feasible in the medium term, may well not bloom unless there is a real need for such sophistication in understanding mineralisation processes. Therefore the future will require a constant recognition of both what the important problems are and which tools are able to address them.

A list of potential developments would therefore have to include:

Incremental advances

1. • Improved precision of existing techniques allowing resolution of signals that were otherwise obscured

Developments in this area will largely be seen in improved geochronology in all forms, allowing detailed petrogenesis histories to be developed, detailing the rates and time scales of mineralising processes. Coupled with these improvements will be improved resolution of initial isotopic ratios resulting in finer distinctions between source regions and contaminants, e.g. Pb and Os isotopes.