YW #2 Leonora Ring – a circular 75km diameter pop-out structure? Discovery of a New Giant Ring Structure – real or imaginary?
Summary. The elevations around the 75km diameter Leonora giant ring structure (GRS) have been examined to determine why there is a well-defined Landsat ring that appears to bear no relationship to the Leonora area geology.
The Permian glaciation planed off the Yilgarn Craton to a level that reached the base of these palaeochannels. Theoretically the area inside the Leonora ring should have been at the average height. Erosion over the last 250 million years has still not reached these lower Permian erosion levels. The almost perfectly circular Leonora ring (the median ring of the Watchorn GRS) appears to be caused by elevation differences which have occurred after Permian erosion, of 10 – 50m, across the ring structure.
This elevation difference was quantified by measurement on Google Earth. This suggests that the whole core of the Leonora ring has popped up and is still rising. This is one of the main criteria of an impact structure.
Streams flow around (or are dammed) by the ring structures on the western half because of this elevation difference. Few streams follow the ring boundary on the eastern half but there is a greater abundance of quartz and vegetation changes around the ring.
The Leonora ring disrupts, and dams the Permian palaeochannels in the SW quadrant, thus the movement must be continuing and recent which suggests subvertical, very deep circular structures are present. The next paper will look at the deeper structure using gravity.
There will be a later paper on seismic correlation with the surface ring structures that addresses this pop out phenomenon.
A paper that details desk top and field studiesf on the Leonora GRS fracture system in the SE quadrant will be published.
There is evidence of a second New GRS centered 70km NNE of the Watchorn GRS – is this a palimpsest?
The attached file details the work and the conclusions of this phase of the research ——
| Leonora ring elevation research | 9.1 MB |