The local bourse is on track for its third day of losses amid fears about the economic outlook, with oil prices plunging on fears of reduced demand even as China relaxed COVID-19 restrictions.
The benchmark S&P/ASX200 index was down 52.8 points, or 0.73 per cent, to 7176.6 at noon AEDT on Thursday, while the broader All Ordinaries had fallen 53.9 points, or 0.73 per cent, to 7369.3.
Nine of the ASX's 11 official sectors were lower at midday, with energy the worst hit as Brent crude plunged under $US80 a barrel for the first time since early January.
Woodside had fallen 3.0 per cent to $34.93, Santos was down 1.3 per cent to $7.075 and Beach had edged 0.2 per cent lower at $1.6375.
In China, the government announced it was easing its zero-COVID strategy, reducing mass testing and letting people isolate at home, but the heavyweight mining sector was still down 0.7 per cent, with BHP retreating 0.6 per cent to $46.34, Rio Tinto declining 1.8 per cent to $113.42 and Fortescue Metals dipping $20.83.
Goldminers were the one bright spot in the market amid the risk-off sentiment, with Newcrest down 2.3 per cent to $21.28, Northern Star up 2.0 per cent to $10.93 and Evolution adding 3.6 per cent to $2.90.
The big banks were mostly lower, with ANZ dropping 1.5 per cent to $23.67, NAB down 0.9 per cent to $30.37 and Westpac down 0.6 per cent to $23.435. CBA was basically flat at $105.51.
Downer EDI had plunged 22.1 per cent to $3.74 after the professional services company announced it had detected $30 million to $40 million in financial accounting irregularities in related to a maintenance contract over a three-year span.
"With oversight by the Board and senior management, a detailed investigation has been initiated and is being treated with highest priority," said Downer, which also announced it was unlikely to meet its full-year guidance given difficult weather conditions in Australia's Eastern States and New Zealand.
Meanwhile, the Australian dollar was buying 67.07 US cents, from 67.04 at Wednesday's ASX close.