Figure 66 above. Pacific – South America – Africa 26°S enhanced seismic tomographic section. Brittle structures shown extending to core.
This fairly complicated figure is section 26° south from South America across the Atlantic to Africa. The original figure is from Hu et al., 2018.
The thing that really stands out in the section is that under the African and South American continents there are brittle structures extending from the surface to the core. Even the small East African Rift has subvertical brittle structures extending to the core.
Questions to answer??
- There is no real evidence of the huge set of vertical structures that one would expect from a 3000 km wide mid-Atlantic Ridge opening.
- There is no evidence of a mobile mantle at all except the turbulent flow to the west of South America.
- I’ll be very interested to see if anyone can prove me wrong on these paradigm changes to the current Plate Tectonic mechanism. That is a challenge for geoscientists to learn how to ultra-enhanced their images – just to prove me wrong ℧.
30. Take away message.
This slide is self-explanatory. I can’t emphasise enough about learning to ultra-detail enhance your images to generate exploration targets. Be aware of all the side paths your research may lead into, follow them up, get out there and explore on the ground.
31. Conclusions
This South American continent evolution is researched using ultra-detailed Landsat, and seismic tomography.
South American is currently believed to have formed during Plate Tectonics and to have progressively accreted over the last 4 billion years.
This study shows that the lithospheric cratons are still continuous under and out to double the extent of the current South American continent. Thus, the original continent most likely was, and has remained, a complete continent up to the present era.
Instead of accreting the South American continent has remained intact over the last 4 billion years despite the action, firstly from vertical tectonics and then Plate Tectonics commencing perhaps 2.7 billion years ago.
South American is a rich source of minerals. The main mining fields in are located on the ring structures and linears as has also been observed in Africa, Australia, North America, China and Fennoscandia. This suggests a close connection between the deeply buried impact structures and mineralisation. Once this relationship has been firmly established, and acted upon for mineral and energy targeting, a giant leap forward will have been made in exploration understanding, targeting and success.
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