APPLICATIONS FOR AUTOSCAN SYSTEMS STAGES : FISSION TRACK DATING
The AS3000i/f stage system consists of an AS3000i stage with AS3500 focus attachment.
This creates an integral 3-axis stage system, which is used in many of our applications.
An alternative to the AS3500 focus attachment is the new series of motorised microscopes with integrated focus drive.
These are used with our latest software, which incorporates automated track counting.
Fission Track Dating (FTD)
The Autoscan Fission Track Dating system consists of :
Autoscan 3-axis stage system (or 2 axes with motorised microscope), Trakscan software and associated hardware and electronics.
Benefits of the Autoscan Fission Track Dating (FTD) system :
The system is primarily used, by our FTD clients, for two purposes :
1. To count the density of fission tracks with a view to establishing the age of a rock sample.
2. To measure the average lengths of fission tracks to establish a likely thermal history.
These measurements are applied both in petroleum exploration, in which the likelihood of finding oil in a given location is assessed by means of determination of the age and temperature history of the rock, and in the fundamental determination of rock age in such locations as Antarctica and the Himalaya ranges, for research purposes. Our major clients are government research departments and universities, with an emphasis in geology.
The key reason why our clients have purchased the Autoscan system is because of the high-precision repositioning capability of the stage, which allows the client to revisit the points of interest within +/- 2 micron in X and Y and +/- 0.2 micron in Z (focus). Also, the execution of the FTD technique is a highly tedious process which our equipment not only simplifies, but for which it delivers a time saving estimated to be at least 85% for an experienced operator.
The latest, most exciting enhancement of Trakscan (which is the result of a 3-year collaborative research project in conjunction with the FTD group at the University of Melbourne, which is headed by Professor A.J.W. Gleadow) is the development of a version of our software which incorporates fully automated counting of fission tracks, both on the apatite grain as well as on the mica. This is a world-first achievement which follows decades of failed attempts by other groups - the many types of artefact and natural defects in apatite crystals, coupled with hitherto insufficiently sophisticated technology, have previously rendered such automation unachievable. In particular, the rise of much faster and more powerful computing hardware and software, as well as the advent of digital cameras with greater image resolution and smaller pixel sizes, have been the enabling factor for this wonderful enhancement of Trakscan. It is now possible to completely bypass a very tedious aspect of the FTD technique - the manual counting of tracks.
A further benefit which has accrued during the development of automated counting is that, because of the ability to store extremely high-quality 3-D images of the tracks in the apatite grain, the subsequent fate of the grain is no longer important. This means that destructive analytical techniques (eg. laser ICP-M analysis) can be employed, without the fear that the original track information will no longer be available. This, in turn, also means that it is possible to avoid the inconvenient and time-consuming nuclear bombardment of the apatite grains (which is currently required in order to elicit secondary emissions. These are in turn measured with a mica detector. The secondary emissions allow the uranium concentration in the apatite to be deduced). The laser ICP-MS technique is able to quantify the concentrations of various elements directly, albeit destructively. However, for those users who prefer to use the radiation-based external detector method (EDM), it is still possible to use our systems in this traditional manner, but with the additional convenience of being able to count the fission tracks automatically in both the apatite grain mount and the muscovite mica external detector material.