<p>You didn't dive deep enough. You're asking about an area on a high-level, generalized map of <a href="https://en.wikipedia.org/wiki/Basement_(geology)" rel="nofollow noreferrer">basement</a> rock provinces.</p>
<p>There were several orogenies at the southern boundary of the Wyoming craton. Between 1800 Ma and 1000 Ma, a series of island arcs accreted to southern Laurentia, building up the pink area on your map.</p>
<p>The earliest of these was the <a href="https://en.wikipedia.org/wiki/Yavapai_orogeny" rel="nofollow noreferrer">Yavapai orogeny</a> between 1800-1700 Ma. It was followed by the <a href="https://en.wikipedia.org/wiki/Mazatzal_orogeny" rel="nofollow noreferrer">Mazatzal collision</a> 1700-1600 Ma.</p>
<p><a href="https://i.sstatic.net/FdCep.gif" rel="nofollow noreferrer"><img src="https://i.sstatic.net/FdCep.gif" alt="Yavapai,mazatal orogeny map" /></a></p>
<p>A 1982 article by Kent C. Condie describes this in more detail. It is <a href="https://pubs.geoscienceworld.org/gsa/geology/article-abstract/10/1/37/203370/Plate-tectonics-model-for-Proterozoic-continental?redirectedFrom=fulltext" rel="nofollow noreferrer">behind a paywall</a>, but you can see the abstract, which gives the gist.</p>

CC BY-SA 4.0
2022-01-20T23:18:35.980Z
2022-01-20T23:18:35.980Z
Spencer
<p>The interpretation of most of these interfaces is uncertain.  Most of these plate boundaries are ancient, poorly exposed, have been metamophosed in later orogenies, and have suffered significant amounts of later erosion making it very difficult to say too much about the earlier character of the contact.  Theoretically, you could have a transform fault that would move different terranes next to each other without having a subduction zone between them but I can't think of any example of this happening today.  The closest would be the San Andreas in California.</p>
<p>Another problem is that it is hard to take our knowledge of plate tectonics today and extend it back billions of years.  Possibly the earth took a long time to come up with its current convection system and the rules were different initially.  None of the other rocky planets seem to have developed  plate tectonics so we know that the current system on earth is not the only way for a planet to behave.</p>

CC BY-SA 4.0
2022-01-20T22:21:40.347Z
2022-01-20T22:42:38.150Z
2022-01-20T22:42:38.150Z
verisimilidude
<p>I have seen this diagram on Wikipedia (link below). It shows that some North American mini-plate boundaries are orogenic bands and some are magmatic arcs, and I think those correspond to continent/continent and continent/ocean crust collisions. But I do not see anything like that at the boundary of the Yavapai/Mazatzal and Wyoming plates. In addition, there are bands marked as passive plate boundaries. How do I interpret these types of boundaries?</p>
<p><a href="https://i.sstatic.net/wxkQG.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/wxkQG.png" alt="enter image description here" /></a></p>
<p><a href="https://en.wikipedia.org/wiki/Trans-Hudson_orogeny" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Trans-Hudson_orogeny</a></p>

<geology><plate-tectonics>
Can continental plates collide and fuse together without an orogenic band or magmatic arc or at the junction?
John McCarthy
# Can continental plates collide and fuse together without an orogenic band or magmatic arc or at the junction?

(Asked by: username_0 on 2022-01-20)

I have seen this diagram on Wikipedia (link below). It shows that some North American mini-plate boundaries are orogenic bands and some are magmatic arcs, and I think those correspond to continent/continent and continent/ocean crust collisions. But I do not see anything like that at the boundary of the Yavapai/Mazatzal and Wyoming plates. In addition, there are bands marked as passive plate boundaries. How do I interpret these types of boundaries?

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

<https://en.wikipedia.org/wiki/Trans-Hudson_orogeny>

**Tags:** geology, plate-tectonics


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## 2 answers

### Answer by username_1 on 2022-01-20. Score: 2

You didn't dive deep enough. You're asking about an area on a high-level, generalized map of [basement](https://en.wikipedia.org/wiki/Basement_(geology)) rock provinces.

There were several orogenies at the southern boundary of the Wyoming craton. Between 1800 Ma and 1000 Ma, a series of island arcs accreted to southern Laurentia, building up the pink area on your map.

The earliest of these was the [Yavapai orogeny](https://en.wikipedia.org/wiki/Yavapai_orogeny) between 1800-1700 Ma. It was followed by the [Mazatzal collision](https://en.wikipedia.org/wiki/Mazatzal_orogeny) 1700-1600 Ma.

[![Yavapai,mazatal orogeny map](https://i.sstatic.net/FdCep.gif)](https://i.sstatic.net/FdCep.gif)

A 1982 article by Kent C. Condie describes this in more detail. It is [behind a paywall](https://pubs.geoscienceworld.org/gsa/geology/article-abstract/10/1/37/203370/Plate-tectonics-model-for-Proterozoic-continental?redirectedFrom=fulltext), but you can see the abstract, which gives the gist.


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### Answer by username_2 on 2022-01-20. Score: 2

The interpretation of most of these interfaces is uncertain. Most of these plate boundaries are ancient, poorly exposed, have been metamophosed in later orogenies, and have suffered significant amounts of later erosion making it very difficult to say too much about the earlier character of the contact. Theoretically, you could have a transform fault that would move different terranes next to each other without having a subduction zone between them but I can't think of any example of this happening today. The closest would be the San Andreas in California.

Another problem is that it is hard to take our knowledge of plate tectonics today and extend it back billions of years. Possibly the earth took a long time to come up with its current convection system and the rules were different initially. None of the other rocky planets seem to have developed plate tectonics so we know that the current system on earth is not the only way for a planet to behave.


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