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我总是听到板块的大块地壳漂浮在地幔就像船一样。在数百万年的时间尺度,甚至碰撞。但我开始认为这只是一个通俗科学不再通俗模型,或methaphor,为一个更复杂的情况。我没有计算但是我觉得印度板块没有大的质量占的令人振奋的喜马拉雅山的动能转移。在这些速度(微不足道,即使大相对于其他板块运动)不会欧亚板块的材料应力吸收所有的动力呢?我得到印度的惯性是巨大的,但这是真的一样继续推动即使在今天吗?如此多的惯性,它仍然还将继续放缓,欧亚大陆?我觉得有一个恒力无关地应用于板的表面,可以解释这一而不是自由移动板块加速砸另一个像两个冰山。板块漂浮的想法像船和他们互动的想法机械碰撞是一个多服用点什么暗示的方式观看这一过程需要整个数量的时间,能量和质量,这样我们,无关紧要的和ephimeral生物,可以在我们的头脑里有一个玩具模型?是印度被强迫或真的就像一个台球移动直到它碰撞与另一个和它的动量变化? ---------- **EDIT:** Ok, so I've actually done the calculation now: [According to the USGS][1], the Indian plate had a speed of $v =9 \; m/century = 2.85\cdot 10 ^{-9}\; m/s$. The [surface area of the plate][2] is $A = 1.19\cdot 10^{7}\; km^2$. If we suppose the thickness of the crust here to be of $h = 50\; km$ (which is thicker than it probably is) then the volume of the plate is $V = A\cdot h= 5.95\cdot 10^{8}\; km^3 = 5.95\cdot 10^{17}\; m^3$. We can estimate the mass of the plate by assuming a density of $\rho = 3\; g/cm^3 = 3\cdot 10^3\; kg/m^3$ (this density is higher than the average we should expect for the crust so [we are not been very conservative at all][3]). Thus the mass of the Indian plate is around $m = \rho V = 1.79\cdot 10^{21}\; kg$ in the best case scenario. Then the kinetic energy of the Indian plate had to be lower than $E_k = \frac{1}{2}mv^2 = 7269\; J = 1.7 \; cal$, which is even less than what @Keith McClary has suggested since this is less than a $1/300 \; th$ of the energy of a candy bar. Now, we can use Newton's Second Law of Motion in the form $\Delta t = mv/F$, where $m$ is the mass of the Indian plate and $v$ is its velocity, to get the time needed to stop the plate, $\Delta t$, when we apply a constant force, $F$, against its motion. Even if the kinetic energy is insignificant it is not easily absorbed during a collision due to the huge inertia of the plate. But still if we suppose $1$ million people, each person pushing with $3000 \; N$ of force then those people could have stopped the continent in less than $\Delta t = 30\; minutes$. A [single weight-lifter][4] would have been able to stop the entire Indian continental plate if he pushed with $F = 8000\; N$ for about $\Delta t = 20.2\; years$. I think that the mechanical stress of the entire eurasian continent creates larger forces that a single human and this "collision" has been going on for millions of years (not 20 years) and is still going on. So this is where it looks absurd to me to talk about a "collision" of plates for the formation of the Himalayas. The driving mechanism has to be a huge force pressing the Indian plate against Eurasia. [1]: https://pubs.usgs.gov/gip/dynamic/himalaya.html [2]: https://www.thoughtco.com/sizes-of-tectonic-or-lithospheric-plates-4090143 [3]: https://en.wikipedia.org/wiki/Continental_crust [4]: https://en.wikipedia.org/wiki/Orders_of_magnitude_(force)

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2

\ begingroup美元一个巧克力。 \ endgroup美元
- - - - - -基思·麦克
因为2019年11月10日
3

\ begingroup美元地幔对流和slab-pull驱动力。这不是关于台球只是随机移动。“台球”正在积极推和拉的力量之下。 \ endgroup美元
- - - - - -Gimelist
2019年11月10日下午4:45过去
1

\ begingroup美元板厚度估计这里是80 - 120英里。这并没有改变你的小能量计算那么多,但值得注意的。theatlantic.com/science/archive/2017/08/… \ endgroup美元
- - - - - -userLTK
2019年11月10日在7:08
\ begingroup美元我不确定这是一个实际的法律,但是我想叫它大数定律。能量很低,由于慢速度的平方但是势头仍然相当高(只有一个速度缓慢的倍数)。同样工作的能力随着时间的推移(能量)很低但力高。运动如果你追溯到地幔内部的循环对流,不是板骑在地幔,你可能会得到更好的数字但仍低能量、高动力。 \ endgroup美元
- - - - - -userLTK
2019年11月11日14时许
\ begingroup美元只是写给你的单位转换。7269 J = 1737卡路里= 1.74千卡= 1.74卡路里。重要的是要区分标准和食品的卡路里因为它们相差1000倍,通常是通过利用“food-calorie”的名称。 \ endgroup美元
- - - - - -帕维尔
2020年3月3日22:18

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