The Deniliquin multiple-ring feature is a distinct deeply buried structure in southeast Australia.

Its characteristics suggest that it is associated with an asteroid impact structure of diameter 520 km (320 mi), which would make it the largest one on Earth, exceeding the largest known one, the Vredefort impact structure of about 300 km (190 mi) in diameter.

The principal features of the Deniliquin structure are a multiple ring total magnetic intensity (TMI) pattern with the minimal TMI ring radius of 260 km (160 mi); a central quiet magnetic zone; circular Bouguer gravity patterns; an underlying mantle Moho rise about 10 km (6.2 mi) shallower than under the adjacent Tasman orogenic zone; and radial faults associated with magnetic and demagnetized anomalies.

[3] Its existence was proposed by Anthony Yeates somewhere between 1995 and 2000, basing in the magnetic patterns in the area.

[1] Glikson suggests that it could have triggered the c. 1.4 million years-long Late Ordovician (Hirnantian) glaciation and the corresponding mass extinction event (445.2 and 443.8 Ma), which eliminated about 85% of species.