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The basis of our work concentrates on petrographic determination of the relative abundance of minerals that are stable during diagenesis
and have similar hydraulic behaviour. The most commonly used ratios are apatite to tourmaline (ATi), rutile to zircon (RuZi), monazite to
zircon (MZi) and chrome spinel to zircon (CZi). These provide a good reflection of source rock characteristics
because they are comparatively immune to alteration during the sedimentary cycle and importantly are stable during deep burial. Zircon
is significantly denser than tourmaline and ratios of these minerals (ZTi) can be used as an indicator of varying hydraulic conditions.
This schematic diagram shows how heavy mineral assemblages are affected by provenance, weathering, hydrodynamics and diagenesis,
and demonstrates how heavy mineral ratios can be used to distinguish provenance-related signals from overprinting processes.
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