Yes the Aptian source rock was proven in Kudu, but there is a...

Yes the Aptian source rock was proven in Kudu, but there is a but... geochemical studies prove that the source for the Kudu gas is the deeper syn-rift lacustrine section (Jurassic lake sediments, more mature) - not the Aptian; Some people have hypothesised that the Aptian might be responsible for the condensate in the Kudu field, with downward migration into the Barremian aeolian reservoir sands (the reservoir in Kudu is deeper than the Aptian).

The Moosehead-1 well in the southwest of PEL87 proved that the Aptian source rock is present there and is good quality (only problem being it was immature/marginally mature). Kabeljouu-1, to the east of PEL87, showed that the Aptian was thin (or perhaps absent) and the quality was poor. In essence, the further outboard you sit, the better the thickness and quality of the Aptian source rock. Hopefully PEL87's position is fine in that regard.

From my understanding, the source rock facies (think quality) in PEL87 should be fine (but it improves westwards as described earlier). The maturity is the big question in PEL87, and by my estimates we should be currently in the oil generation window in the eastern half of the block (below Saturn) and maturity increases to the east. Hopefully there is enough good quality, mature source rock to charge the enormous volumes quoted for Saturn.

I am uncertain as to where the Woodside 3D survey covers, but I suspect it doesn't extend out to the far west of the block where the Aptian is considered too immature for oil generation (ie not buried deeply enough).

The recent oil discoveries have been used to fine tune the model for source rock maturity, and Saturn now becomes more appetising, as it was previously considered to be located over an area of marginally mature source rock.

Apologies for the geology waffle...