Recognising basin inversion.... by sketch restoration

[@cybernescens]

I love these deep dives, so engaging. Thanks Professor.

[@evanbrown2594]

Excellent! I work as a petroleum geoscientist and the methods used here are great skills for anyone in earth science to practice.

[@IlluminateYourMind247]

Thank you very much, Rob Butler, for this insightful video.

[@guilhermeborsa]

Cheers from Brazil! As usual, a very good lecture!

[@Intact9]

Thank you for the informative video.

[@2124693]

great video. Amazing.

[@HamzehRezaei-dp7sc]

Thank you

[@turalahmadov8431]

Thanks a lot for sharing useful geological content. I have a question about, is it possible that, when normal fault reactive, its accompany also with strikes-slipe events? .

[@robbutler2095]

yes of course, but we can't get into these 3D issues in a 2D profile...

[@turalahmadov8431]

@@robbutler2095 Thats a lot for quick response Mr.Butler, i got it

[@dr.douglashaywick9517]

Thanks, Rob, for these great videos! Quick question: Could this be considered horizon flattening rather than seismic restoration, since the lateral distance remains unchanged? For true restoration, wouldn’t you need to account for changes in XX' distance?

[@robbutler2095]

Well indeed - we are flattening on the X-X' horizon, and it could be done using seismic software ... though you'd need the picks to be in too. Of course, for any restoration (extension or contraction) there will be a change in horizontal distances too... which is what would come next... but to test the basic idea of inversion and finding which faults have reactivated, I'd always do a first pass as in the film.

[@AvanaVana]

Wouldn’t the original normal faults still be listric? And how do you restore the original extension? I noticed that the distance between X and X’ was the same in both sections, but before inversion the section should be longer, no? And are the ages of the faults all the same? Or is the purpose of this exercise merely to judge the general magnitude of inversion on each fault individually, and not necessarily to restore the whole section?

[@robbutler2095]

Thanks for the comments. As stated - this was a quick look approach. Of course the horizontal distance between X and X' would have decreased during inversion.But restoring this would be far more elaborate. The ideais to do a quick pass as shown first to get an idea of what's happened, then focus in.

[@hongyuanZhang-pr6wt]

​@@robbutler2095From the example, it is clear that the first extension stage (ES) is replaced by the second contraction stage (CS). In ES, the orientation of the minimum principal stress (σ3 = σh) is parallel to σ1 = σH in CS. This is indeed a textbook definition of an inversion fault, which is a type of fault that experiences several stages of movement along the same fault plane. However, regional inversion can also occur even when the orientations of σH and σh do not change significantly, but σV changes from being the largest to the smallest compared to σH and σh. Basin inversion also occurs, though not on the same fault plane. What do you think about this other type of inversion?