I think you are correct. The dark quadrants are compressional first motion and the light quadrants are dilatational (first motion down). I think he confused the principal stresses with first motions.
This is a really great demo. There's a point of confusion with sigma1, though (at least in my brain). Sigma1 (max. princ. stress) should generally be 30 deg from the fault plane, so it would not be exactly in the center of the white portion of the plot. Wouldn't sigma1 be 60 deg from the aux. plane?
Thanks a lot for your efforts. I was wondering why did you count through the small circles a 90-degree angle starting from the rake position to put another point on the same great circle that represents the fault plane? Also why did we start counting the rake angle itself from the right not from the left?
Thank you Casey!
Thank you very much man, this is really helpful
It's so helpful and informative video .. Thank you
thanks for this video.
I thought the dark quadrants were the compressional waves, not dilational.....
I think you are correct. The dark quadrants are compressional first motion and the light quadrants are dilatational (first motion down). I think he confused the principal stresses with first motions.
This is a really great demo. There's a point of confusion with sigma1, though (at least in my brain). Sigma1 (max. princ. stress) should generally be 30 deg from the fault plane, so it would not be exactly in the center of the white portion of the plot. Wouldn't sigma1 be 60 deg from the aux. plane?
Thanks a lot for your efforts. I was wondering why did you count through the small circles a 90-degree angle starting from the rake position to put another point on the same great circle that represents the fault plane?
Also why did we start counting the rake angle itself from the right not from the left?
How can i derive if i have a normal plane fault or reversed fault, when i have only given the 3 parameters, strike, dip and rake?
Make more videos related to stereo net. Thanks