Perth Abyssal Plain - Option 3, Suggested Placement of Williams et al. (2013), ID: 2-7-3-1

Time of cessation: 120 Ma, after M0 (Williams et al., 2013)


This suggested extinct ridge axial placement is supported by interpreted magnetic anomalies on the Perth Abyssal Plain, however there is no bathymetric or gravity feature that can be identified as the former axis of spreading. The bathymetric relief in the region of the inferred axis is within a standard deviation of mean of the 'well-defined' extinct ridges, because a number of well-defined examples have little surface expression due to thick sediment cover. There is a lack of a clear gravity signal in profile. It is possible that this was a former axis of spreading that experienced a very rapid transfer to a new location, but there is limited support for an extinct ridge formation other than the magnetic anomalies reported from teh study of Williams et al. (2013).


Williams, S.E., Whittaker, J.M., Granot, R., Müller, R. D, 2013, Early India-Australia spreading history revealed by newly detected Mesozoic magnetic anomalies in the Perth Abyssal Plain, Journal of Geophysical Research: Solid Earth, v. 118, no. 7, p. 3275–3284.

Maps showing the location of extinct ridge segments

Depth profiles across the axes of extinct ridge segments

Gravity profiles across the axes of extinct ridge segments