I did register another lithology in the section model given. Syenite - a common associate of carbonatite intrusives.



This section is partially described in the Jorc Appendix. A lot of the variations are defined by multi element geochem.

Models of the major lithologies and weathering profile weregenerated and used as key primary constraints on gradepopulations. They were interpreted from the multi-elementgeochemistry with support from core and RC chip logging. from Jorc appendix


The central core is dominantly carbonatite.
Modelled lithologies include the gneiss country rock to thesouthwest, undifferentiated wall rocks intruded by a complexcarbonatite pluton and dyke swarm and all overlain by transportedsediments. The morphology of the carbonatite intrusion is complex,with a broad zone of dominantly carbonatite in the south,


The surrounding carbonatite complex is just that at this stage (and probably will remain so). A mix of country rock (variably altered) and carbonatite dykes/?breccia? maybe...
surrounded by a wide and gradational contact zone with theencompassing wall rock. This ‘mixed zone’ is complex and containscomagmatic silicates and/or wall rock xenoliths and carbonatitedyke swarms on a scale of cm to 10s of meters, resulting incomplexity in the primary lithology at a scale that is notable in thetightest drillhole spacing (i.e. 25m) and twin hole pairs.

[Xenoliths - chunks of "exotic" rocks "floating" in the carbonatite intrusion.]

The fenite zone is strongly altered and very much a work in progress. Geochemistry is likely one of the main ways to try and understand what original rock types were.

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The above is background for how the lithologies were used to create basic domains. No real surprise that the carbonatite is the main Nb source and reflects the simplified geology.
Of key importance is that Nb is present in the carbonatitelithology, and segregating areas of predominantlycarbonatite/mixed zone and wall rock, from the wall rock was animportant first step towards establishing the geological architecturein preparation of the generation of estimation domains.

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Weathering zone covered by some transported.

The carbonatite hasa well-developed chemical weathering profile, commonly rangingfrom 30m to 70m. Local areas of deep weathering, over 150m indepth, likely represent complex karst geometries in thepaleosurface.

[Karst topography Carbonatites by definition are >50% carbonates and can be weathered like various limestone terrains around the world. Think of areas in China and Thailand and....



These images are large scale but they range greatly in size .

The research is to try and understand what is going on. Helps me get a feel for possible trends and other aspects for EnR

Enough geology. Goodnight all.