Re: On the detection of the Wilkes Land impact crater

On 4/13/25 7:48 PM, erik simpson wrote:

On 4/13/25 5:35 PM, John Harshman wrote:

On 4/13/25 9:07 AM, erik simpson wrote:

https://earth-planets-space.springeropen.com/articles/10.1186/s40623-018-0904-7
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Abstract
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The definitive existence of a giant impact crater, two times larger than the Chixulub crater in the Yucatan peninsula, from an extraterrestrial origin, 1.6 km beneath Wilkes Land, East Antarctica, remain controversial. Here, we use the latest high-resolution gravito-topographic geopotential (SatGravRET 2014) model over Antarctica to offer a plausible confirmation of its existence. SatGravRET 2014 has a spatial resolution between 1 and 10 km at most places and included contemporary space gravimetry and gradiometry data from GRACE and GOCE, and other data including Bedmap 2 bedrock topography. We computed the gravity disturbances, the Marussi tensor of the second derivatives of the disturbing potential, the gravity invariants and their specific ratio, the strike angles and the virtual deformations to quantify the detailed geophysical features for the Wilkes Land anomaly. This set of the gravitational parameters revealed enhanced and more detailed geophysical features on the Wilkes Land Crater than previously possible only with the traditional gravity anomalies. Our findings support prior studies stating that in the Wilkes Land there is a huge impact crater/basin with detectable gravity mascon which is mostly consistent with the characteristics of an impact crater.
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The discussion includes the following: "These results widen space for geophysical interpretations and speculations. The huge impact had a planetary consequence, including for example the striking antipodal relationship of it to the Siberian Raps (claimed by von Frese et al. 2009).".
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If "Siberian Raps" really means Siberian Traps, the paleontological implications are obvious.

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I'm supposing it would be very difficult to date this impact. Is the association with the Siberian traps solely their antipodal position? Would that have been true at the time of the traps?

 Not sure about the positioning.  Getting a date would involve a lot of deep drilling.  I also wonder if there is any record of finding tektites from such an impact.  I've no idea of how long they would last.

My understanding is that nobody has ever found any evidence of an end-Permian impact, despite extensive searches. Nothing at all like the K/T boundary clay, which really ought to be there in any sediments of the proper age. Of course the association of the crater, if it's really a crater, with the end-Permian extinction appears to be pure speculation. They only claim that it must be more than 100ma and less than 500ma.