# Tectonic plates shifted causing wobbling of the Earth axis?

**URL:** <https://boards.straightdope.com/t/tectonic-plates-shifted-causing-wobbling-of-the-earth-axis/282377>\
**Category:** Factual Questions\
**Created:** [December 31, 2004, 4:32am UTC](https://boards.straightdope.com/t/tectonic-plates-shifted-causing-wobbling-of-the-earth-axis/282377 "2004-12-31T04:32:15Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![Kel\_Varnsen\_Latex\_Division](https://avatars.discourse-cdn.com/v4/letter/k/aeb1de/32.png) [@Kel\_Varnsen\_Latex\_Division](https://boards.straightdope.com/u/Kel_Varnsen_Latex_Division)\
**Post date:** [December 31, 2004, 4:32am UTC](https://boards.straightdope.com/t/tectonic-plates-shifted-causing-wobbling-of-the-earth-axis/282377/1 "2004-12-31T04:32:15Z")

</div>

Did the recent earthquake cause tectonic plates to permanently shift, causing some wobbling of the Earth axis?

---

<div class="post-metadata">

**Author:** ![Kel\_Varnsen\_Latex\_Division](https://avatars.discourse-cdn.com/v4/letter/k/aeb1de/32.png) [@Kel\_Varnsen\_Latex\_Division](https://boards.straightdope.com/u/Kel_Varnsen_Latex_Division)\
**Post date:** [December 31, 2004, 7:05pm UTC](https://boards.straightdope.com/t/tectonic-plates-shifted-causing-wobbling-of-the-earth-axis/282377/2 "2004-12-31T19:05:43Z")

</div>

Bump.

---

<div class="post-metadata">

**Author:** ![Kythereia](https://avatars.discourse-cdn.com/v4/letter/k/e8c25b/32.png) [@Kythereia](https://boards.straightdope.com/u/Kythereia)\
**Post date:** [December 31, 2004, 7:08pm UTC](https://boards.straightdope.com/t/tectonic-plates-shifted-causing-wobbling-of-the-earth-axis/282377/3 "2004-12-31T19:08:31Z")

</div>

Australian seismologist Clive Collins says yes [here](http://www.theage.com.au/news/Science/Islands-rise-and-fall-as-Earth-throws-a-wobbly/2004/12/29/1103996611343.html?oneclick=true).

---

<div class="post-metadata">

**Author:** ![rfgdxm](https://avatars.discourse-cdn.com/v4/letter/r/c0e974/32.png) [@rfgdxm](https://boards.straightdope.com/u/rfgdxm)\
**Post date:** [December 31, 2004, 7:10pm UTC](https://boards.straightdope.com/t/tectonic-plates-shifted-causing-wobbling-of-the-earth-axis/282377/4 "2004-12-31T19:10:12Z")

</div>

Yes, but this real issue is _materially_. If I were to go to the top floor of the Empire State building, this would insignificantly alter the rate of rotation of the Earth due to conservation of angular momentum.

---

<div class="post-metadata">

**Author:** ![Valgard](https://avatars.discourse-cdn.com/v4/letter/v/7feea3/32.png) [@Valgard](https://boards.straightdope.com/u/Valgard)\
**Post date:** [December 31, 2004, 7:42pm UTC](https://boards.straightdope.com/t/tectonic-plates-shifted-causing-wobbling-of-the-earth-axis/282377/5 "2004-12-31T19:42:34Z")

</div>

Technically ANY movement of anything on the earth will affect the entire planet’s motion, and massive earthquakes certainly do cause detectable wobbles all over the world.

That being said, the crust of the earth is only a tiny, tiny fraction of the total mass of the planet. If a small piece of the crust moves around a bit, the overall effect on the planet is going to be pretty insignificant.

As a rough idea of the scale, if the earth was the size of a pool ball (2.25" diameter), the crust would be a shell on the order of 0.01" thick.

So sure there’s movement but it’s not like the earth is suddenly hopping around like an unbalanced washing machine.