Comparing Test Line Inversion Results from Different Helicopterborne Transient Instruments with Regard to Hydrogeological Mapping

Abstract

The selection of an appropriate instrument for the data collection is one of the most important issues to address in survey design. Both theoretical analyses of the resolution capabilities of the candidate systems and field tests should be part of a selection process. It is also quite clear that any comparison must be performed based on the specific criteria of the survey. In this presentation we will concentrate on the field test aspects of the system selection process and compare the results of inverting data from three different helicopterborne systems: the VTEM system, the SkyTEM312 system, and the SkyTEM312FAST, that were flown over the same test lines. The bench marks of the comparison were mainly the near-surface resolution capabilities, both vertically and horizontally, and the resolution at depth. The results of our study show that in certain parts of the test lines both SkyTEM systems have a better near-surface vertical and horizontal resolution than the VTEM system, but that in other parts of the test lines differences are small. The depth penetration seems to be approximately the same for all three systems. The differences between the SkyTem312 and the SkyTem312FAST are almost imperceptible.