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I have read about all 3 types of boundaries in the book : "Essentials of Geography" by Lutgens et. al. But there is nothing mentioned about Transform Boundary and Earth's rotation effect on it.

I know the basics that since MoR are not always in straight lines, so there is a differential moment between two portions of the plate which cause this transform boundary that is perpendicular to the MoR.

But now, when I was reading one of the 'official' book of this subject by NCERT I got stuck on this paragraph :

Transform Boundaries : Where the crust is neither produced nor destroyed as
the plates slide horizontally past each other.Transform faults are the planes of 
separation generally perpendicular to the midoceanic ridges. As the eruptions do 
not take all along the entire crest at the same time, there is a differential 
movement of a portion of the plate away from the axis of the earth. Also, the
rotation of the earth has its effect on the separated blocks of the plate portions.

[This] is where this is mentioned. Now I'm really not able to relate Earth's rotation, axis, and its effect on transform boundary. Neither Google is giving any meaningful result.

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NCERT is an Indian document written from the perspective of the prevailing non-scientific educational culture, in which (for example) astrology is considered to be bona-fide science! Therefore it is not authoritative, and certainly not written accurately from the perspective of peer-reviewed scientific sources. It has been criticized before, and in this case it is quite incorrect to write that transform faults are significantly affected by the Earth's rotation. Rather, the NCERT quotation that you cite seems to confuse the Earth's pole of rotation with the Euler pole of rotation. The latter is a key concept of the plate tectonic movement between any two plates. The Euler pole of rotation can be at any angle with respect to the Earth's rotational axis.

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  • $\begingroup$ Thanks for the respond Gordon. Seems like the reputation of NCERT wrt to non-scientific/ancient jingoism is wide prevalent outside of India too. Not a good thing for us students too. The thing is, in our open recruitment exams, what is written in NCERT is considered to be sacrosanct, and if this questions came in exam I would have much dilemma whether to take this statement "transform boundary are affected by earth rotation" as right or wrong. anyway, Any pointer to study a bit more about Euler pole of rotation? Though I'll google thoroughly. $\endgroup$ – Maverick33 Jun 25 '16 at 7:46
  • $\begingroup$ youtube.com/watch?v=_0mdH8NtJXE This video cleared all the doubts :) But I still couldn't understand this phrase "there is a differential movement of a portion of the plate away from the axis of the earth", even considering this axis is Euler axis. Any idea? $\endgroup$ – Maverick33 Jun 25 '16 at 8:23
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    $\begingroup$ I also think this is a confusing statement. I think what they are getting at is that all plate movements eventually weaken, in which case the plate is jostled in a different direction by adjacent plate motions, and this results in a deviation away from a former Euler axis. $\endgroup$ – Gordon Stanger Jun 25 '16 at 10:07
  • $\begingroup$ And clearly, the last line that "earths rotation has its effect on separated blocks of plate boundaries" is incorrect, right? $\endgroup$ – Maverick33 Jun 25 '16 at 10:12

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