Mea culpa for point 1. Let me know if this helps.Perce and Luni...

Mea culpa for point 1. Let me know if this helps.

Perce and Luni both strong Gravity
Perce the weakest of magnetics vs Luni moderate mag from ground surveys though wispy on airmag,

Perce is an intense gravity (whoops before) feature c6 Milli-gals (whatever the units are called). From memory, I think WR (or someone from ENR at an AGM) said OD was 9 Mg and one of the stronger responses in OZ - did not check this statement. If correct then Perce is very strong in a relative sense.

What would cause such a gravity anomaly WITHOUT any more than the faintest of magnetic signatures? Ga*bbro at Caird, Lamprophyre at Crean south and perhaps BIF at Hoschke give coincident mag and gravity. Somehow such rock types, or something else, may be de-magnetised at Perce. Hence, the idea of intense hematite alteration which changes the host without removing the gravity.

On the ENR mag there do appear to be some very subtle magnetic features at Perce.
Zooming in on the mag image:



In the past I thought there was no magnetic feature at Perce. But, when putting the original post together I noticed there is something, albeit very subtle compared to Wordie and further west. If real I suspect there is deep cover or a tremendous level of alteration.



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Some geopoetry musings.

The faulting in the Aileron area does seem to create an almost basin and range (Nevada and surrounds) style of vertical tectonics/faulting.

Lateral movement is hinted at by off set magnetics at Luni/Sambahr and perhaps the dismemberment of BIF style Reynolds range formation units. (Agrimin mag anomaly/Sambahr and Urmia prime possibilities). Another strong mag feature on Tali ground had BIF mentioned in Toro reports from 15 years ago (from memory)


Possible and simplistic sequence of events for a small area near Luni.
1 formation of magnetic gravity feature Sambahr (Possibly 1760-1805 My Reynolds Range group)
2 Sinistral (left hand sense) faulting off sets northern portion to SW.
3 Not clear Endurance fault is not offset so may cut 2.
4 not clear but intrusion of Luni/Emily/Green.



Cover (later sediments, weathering) tends to mute the magnetic signature. Only very strong or shallow sources make it through the sea of the later basinal sediments (Murraba, Hidden, Canning). The Top up Rise IOCG target is an example of this - drilling did intersect sub economic copper (another story perhaps related to RCR in a way).


Separate post for the other points.