Under the new earnings scheme for partner airlines with Iberia, a CHC-MEL-DOH-LHR round-trip in business on QF & QR nets (350+1750+1250)*2 elite points, or 6700 elite points – which is short of oneworld Sapphire (7500 needed).
If you book and fly before 1 April, when the scheme changes, then you'd earn (115+600+500)*2, or 2430 elite points – and yes, this would be enough for oneworld Sapphire (2250 needed).