<p>If two continental plates meet, neither generally subduct -- you just get a big collision, in the way the Alps and the Himalayas are formed. That's because continental plates are relatively light, and neither wants to disappear into the mantle.</p>
<p>If a continental and an oceanic plate meet, the oceanic plate (being denser) generally loses the battle and subducts. If two oceanic plates meet, it's a toss-up.</p>

CC BY-SA 4.0
2023-02-20T00:18:40.233Z
2023-02-20T00:18:40.233Z
Wolfgang Bangerth
<p>I'm working through Artifaxian's (<a href="https://www.youtube.com/watch?v=AzD_WVsEIRM" rel="nofollow noreferrer">https://www.youtube.com/watch?v=AzD_WVsEIRM</a>) series on using gPlates to make tectonic history.  I've run into the place where I have two subduction ridges about to meet.  The bottom continent is moving up, the one at the top is moving down. Which one is likey to subduct?</p>
<p>I can imagine that the unified front of the bottom subduction could make it easier for it to take under the top subduction zone.  Likewise I could imagine that the sharp point could pierce the bottom one.</p>
<p>The ocean crust segments are the same age.</p>
<p>Thanks for any thoughts and ideas you share!</p>
<p><a href="https://i.sstatic.net/hyIZx.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/hyIZx.png" alt="enter image description here" /></a></p>

<geology><plate-tectonics><tectonics>
Speculative Plate Techtonics - Resolving intersecting subductions
Stephen Rider
# Speculative Plate Techtonics - Resolving intersecting subductions

(Asked by: username_0 on 2023-02-17)

I'm working through Artifaxian's (<https://www.youtube.com/watch?v=AzD_WVsEIRM>) series on using gPlates to make tectonic history. I've run into the place where I have two subduction ridges about to meet. The bottom continent is moving up, the one at the top is moving down. Which one is likey to subduct?

I can imagine that the unified front of the bottom subduction could make it easier for it to take under the top subduction zone. Likewise I could imagine that the sharp point could pierce the bottom one.

The ocean crust segments are the same age.

Thanks for any thoughts and ideas you share!

[![enter image description here](https://i.sstatic.net/hyIZx.png)](https://i.sstatic.net/hyIZx.png)

**Tags:** geology, plate-tectonics, tectonics


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## 1 answers

### Answer by username_1 on 2023-02-20. Score: 3 | Accepted answer

If two continental plates meet, neither generally subduct -- you just get a big collision, in the way the Alps and the Himalayas are formed. That's because continental plates are relatively light, and neither wants to disappear into the mantle.

If a continental and an oceanic plate meet, the oceanic plate (being denser) generally loses the battle and subducts. If two oceanic plates meet, it's a toss-up.


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