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For the past 50 million years, India has been crashing into mainland Asia, creating the Himalayan range and uplifting Tibet, north of the mountains, to a current average height of 4500 meters above sea level.

But why is Tibet the one getting an uplift? Why isn't India, instead?

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  • $\begingroup$ Well, for one, the Indian plate is under thrusting beneath the Eurasian plate. Also, the broadness of the Tibetan plateau is likely related to lower crustal processes. $\endgroup$
    – stali
    Commented Apr 24, 2016 at 1:33
  • $\begingroup$ Could you clarify, please? $\endgroup$
    – JohnWDailey
    Commented Apr 24, 2016 at 2:07
  • $\begingroup$ @gansub Why bring it up as though it were a big issue? $\endgroup$
    – JohnWDailey
    Commented Apr 25, 2016 at 12:24

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The simple answer is 'crustal thickness'. The two crustal plates of India and Eurasia are very different in character. The Indian plate is thin, the Eurasian plate is much thicker and more rigid. Both plates are so buoyant with respect to the underlying mantle that neither can subduct in the normal sense. But India is moving so fast that something has to give. The Indian plate is buckling a bit, but mostly being under=plated at low angle as the Eurasian plate rides over it - as it did is such spectacular fashion during last year's Nepalese earthquake.

PS the main continent-continent crunch occurred some 40 to 20 million years ago.

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  • $\begingroup$ I don't understand the PS part. $\endgroup$
    – JohnWDailey
    Commented Apr 25, 2016 at 22:56
  • $\begingroup$ John W.D. mentioned that India has been crashing into Asia for the last 50 million years, which is true in a way, but it's more complicated than that. Although the process still continues the main collision period was about 40 to 20 million years ago. See, for example, the tectonic section of my paper "A palaeo-hydrogeological model for arsenic contamination in southern and southeast Asia" Env. Geochemistry & Health. (2005) 27, 359-367. $\endgroup$
    – Gordon Stanger
    Commented Apr 26, 2016 at 9:39
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    $\begingroup$ This answer would benefit from some references and/or links. $\endgroup$
    – Matt Hall
    Commented Apr 26, 2016 at 14:02
  • $\begingroup$ That makes me curious what some of the larger earthquakes were like 20-40 million years ago. Nice, interesting answer. (not disagreeing with @kwinkunks on more links), but, I learned something reading that. $\endgroup$
    – userLTK
    Commented May 23, 2016 at 4:16
  • $\begingroup$ Another good read is Kumar et al (2007). nature.com/nature/journal/v449/n7164/abs/nature06214.html $\endgroup$
    – user2821
    Commented Jun 1, 2016 at 9:04

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