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Mount Kinabalu is a 13,400 foot mountain in North Borneo formed by volcanism about ten million years ago. What caused this volcanism, why has volcanism ceased in Borneo, and what was the cause of the earthquake which shook the Kinabalu area in 2015?

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According to Cottam et al. (2013), Mount Kinabalu was not formed by volcanism. It is a granite pluton, so it was emplaced in the crust as an intrusion, and later exhumed. The authors mention rollback of the subducting Celebes Sea as the cause for extension and magmatism in the region.

As for the earthquake, I can't answer this part, sorry.

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  • $\begingroup$ A 13,000 foot mountain must require a lot of exhumation. Ten million years may seem a long time, but on a geological timescale it isn't much So far as I can tell Borneo is well away from any plate margin, so the usual causes of volcanism and earthquakes seem unlikely. $\endgroup$ – Michael Walsby Nov 26 '19 at 18:26
  • $\begingroup$ Well, if you look at the paper I cited, you'll see that the authors calculate an exhumation rate of 7 mm per year, which they indeed coin as "extremely rapidly", but they later explain that it "reflects the extreme upper end of the likely range", and that it is "comparable with those reported from areas of active exhumation such as the Greater Himalaya, the Southern Alps of New Zealand and the European Alps". $\endgroup$ – Jean-Marie Prival Nov 27 '19 at 9:06
  • $\begingroup$ @ Jean-Marie Prival I've been wondering if the pluton was much nearer sea level when erosion began to exhume it, and it's present height is the result of millions of years of pressure from below, which is still raising it at a rate of 5mm per year. $\endgroup$ – Michael Walsby Nov 27 '19 at 9:28
  • $\begingroup$ Cottam et al. suggest that the region was already uplifted during the Miocene due to the Sabah orogeny, "creating a topographic feature into which the Kinabalu granite was intruded". So the crust where the granite was emplaced was already above sea level at the time of the intrusion, even if the pluton itself "was emplaced at a depth of between 12 and 7 km" (that is below crust surface, not sea level). $\endgroup$ – Jean-Marie Prival Nov 27 '19 at 10:07
  • $\begingroup$ @ Jean-Marie Prival Nevertheless, it is rising at 5mm per year, and my guess is that this has been going on for millions of years. The recent earthquake was quite a severe one, and killed 18 people. $\endgroup$ – Michael Walsby Nov 27 '19 at 10:16

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