<p>I disagree with Michael about the "not as large as the lunar mare" part. <a href="https://doi.org/10.1016/0016-7037(92)90183-J" rel="nofollow noreferrer">Head and Wilson (1992)</a> mention that the "total area of exposed mare deposits is about 6.3 millions km<sup>2</sup>" (17 % of the Moon's surface area). They estimated a total volume of 10 millions km<sup>3</sup>. The largest mare, <a href="https://en.wikipedia.org/wiki/Oceanus_Procellarum" rel="nofollow noreferrer">Oceanus Procellarum</a>, covers about 4 millions km<sup>2</sup>.</p>

<p>These values are quite comparable with Large Igneous Provinces (LIPs) in terms of area, and are even one order of magnitude lower in terms of volume. From the <a href="https://doi.org/10.1016/B978-0-12-385938-9.00014-6" rel="nofollow noreferrer">Encyclopedia of Volcanoes</a>:</p>

<blockquote>
  <p>The composite Ontong-Java-Manihiki-Hikurangi plateau covers 3.5
  million km<sup>2</sup> with an estimated volume 59-77 million
  km<sup>3</sup>. [...] The Kerguelen plateau in the southern Indian
  Ocean is the second largest LIP, covering 2.3 million km<sup>2</sup>
  with a volume of 15 million km<sup>3</sup> [...] Not all LIPs are
  oceanic plateaus; for example, the North Atlantic volcanic province,
  derived from a hot spot presently centered beneath Iceland, has an
  area of 1.3 million km<sup>2</sup> [...] Also notable are the Deccan
  traps in India (1.8 million km<sup>2</sup>/9.3 million
  km<sup>3</sup>).</p>
</blockquote>

<p>If lunar maria seem that large from Earth, it's only because the Moon is small!</p>

<p>But <strong>to know if lunar maria or LIPs would have looked like "glowing lava oceans shinning in the night", we need to look at emplacement rates rather than just areas and volumes</strong>. From the same chapter, one can calculate LIP emplacement rates of ~3-13 km<sup>3</sup> per year. It may seem quite low (for comparison, ocean ridges quietly produce ~20 km<sup>3</sup> per year), but it is an average output rate over a few million years. As noted on <a href="http://www.largeigneousprovinces.org/frontiers#melt" rel="nofollow noreferrer">largeigneousprovinces.org</a>, their might be pulses of magmatic activity, with peaks in production rate. This is exactly what's been inferred for lunar maria by <a href="https://doi.org/10.1016/j.icarus.2015.12.039" rel="nofollow noreferrer">Wilson and Head (2017)</a>: even if the average output rate has been calculated at a very low 0.01 km<sup>3</sup> per year, they found that some flows could have been emplaced with rates up to 10<sup>6</sup> m<sup>3</sup>s<sup>-1</sup>!</p>

<p>As to whether this would have been visible from space: define "from space"! From low Earth orbit like the ISS? From the Moon itself? :)</p>

CC BY-SA 4.0
2019-12-11T17:44:34.290Z
Very interesting. When I say "seen from space" I imagine a view like the one from Geostationary satellites or the Moon. I know this would be clearly visible from the ISS since volcanic eruptions are usually visible, but I would like to know if LPIs would look like glowing red patches just as lunar marae looked a long time ago from Earth, or would the smoke block the view.
Swike
CC BY-SA 4.0
2019-12-12T08:37:42.657Z
I guess it depends where the lava is emplaced. On barren land, where there is not much to burn, you could probably see lava glowing at night. But to witness a better show, you should probably go back in time to the Hadean and look at the magma ocean.
Jean-Marie Prival
CC BY-SA 4.0
2019-12-11T13:37:07.400Z
2019-12-11T13:37:07.400Z
Jean-Marie Prival
<p>Yes, there would have been seas of lava glowing in the night, but not as large as the lunar mare. The lunar mare were caused by asteroids punching through the then thin lunar crust and releasing a flood of magma from  below, as well as producing some magma of their own from the heat of impact. There is no evidence of anything of that nature causing the Deccan Traps or the Siberian Traps. There must have been some smoke and haze from both super-eruptions, but not enough to hide them from an observer in space in the unlikely event that there were any. Much of the incinerated trees and other vegetation were covered by sheets of lava, and therefore could not release much smoke and fumes.</p>

CC BY-SA 4.0
2019-11-10T03:02:59.607Z
In the case of the Siberian Traps, the rocks overlying the eruptions apparently contained large coal beds, which were set on fire by the eruptions.  Also, you seem to be assuming one continuous super-eruption, rather than an ongoing series of eruptions lasting from 30 thousand to a couple of million years: https://en.wikipedia.org/wiki/Deccan_Traps https://en.wikipedia.org/wiki/Siberian_Traps
jamesqf
CC BY-SA 4.0
2019-11-10T09:15:41.527Z
How did the oxygen needed to support the combustion get through many metres of lava? Anyway, the question refers specifically to the Deccan Traps.
Michael Walsby
CC BY-SA 4.0
2019-11-10T13:57:20.993Z
@jamesqf If it were a series of eruptions instead of a continuous super-eruption what would the difference be in terms of the view from space? Less area covered with magma? Less spectacular than Lunar Mare?
Swike
CC BY-SA 4.0
2019-11-10T17:39:40.500Z
@Michael Walsby: Presumably the same way it gets to underground coal fires today: https://en.wikipedia.org/wiki/Coal-seam_fire  (At the question doesn't ask about the Deccan Traps specifically, it asks about  large igneous provinces, using the Deccan Traps as an example.)
jamesqf
CC BY-SA 4.0
2019-11-10T17:45:52.390Z
@Swike: I don't think it would be really spectacular at all.  It would be more like the  Hawai'ian volcanos (with a more fluid lava that doesn't pile up) spread over a large area: occasional eruptions, but mostly nothing.  Or maybe the Cascades: https://en.wikipedia.org/wiki/Cascade_Volcanoes  Lots of volcanic activity on a million-year timescale, yet only two significant eruptions in a very long human lifespan.
jamesqf
CC BY-SA 4.0
2019-11-10T20:08:02.943Z
@jamesqf Interesting, so when I see maps like these (https://www.eurekalert.org/multimedia/pub/web/99808_web.jpg) I shouldn't assume that the shaded area was entirely covered by lava in any particular time?
Swike
CC BY-SA 4.0
2019-11-11T03:45:41.940Z
@Swike: Almost certainly not, though I'm far from being an expert.  It seems much more likely to have been built up by many eruptions over thousands or millions of years.
jamesqf
CC BY-SA 4.0
2019-11-11T12:32:48.230Z
@jamesqf Thank you so much, if you put this information as an answer I will select yours for sure.
Swike
CC BY-SA 4.0
2019-11-09T18:25:47.030Z
2019-11-09T18:25:47.030Z
Michael Walsby
<p>Would Large Igneous Provinces like the Deccan Traps have looked like ancient lunar Mare from space? Glowing lava oceans shinning in the night?</p>

<p>Are these two things similar in nature? Would smoke from these regions fill the atmosphere with a haze that would hide the view from space?</p>

<volcanology><igneous>
Large Igneous Provinces are like Lunar Mare?
Swike
# Large Igneous Provinces are like Lunar Mare?

(Asked by: username_0 on 2019-11-09)

Would Large Igneous Provinces like the Deccan Traps have looked like ancient lunar Mare from space? Glowing lava oceans shinning in the night?

Are these two things similar in nature? Would smoke from these regions fill the atmosphere with a haze that would hide the view from space?

**Tags:** volcanology, igneous


---

## 2 answers

### Answer by username_1 on 2019-12-11. Score: 2 | Accepted answer

I disagree with username_2 about the "not as large as the lunar mare" part. [Head and Wilson (1992)](https://doi.org/10.1016/0016-7037(92)90183-J) mention that the "total area of exposed mare deposits is about 6.3 millions km2" (17 % of the Moon's surface area). They estimated a total volume of 10 millions km3. The largest mare, [Oceanus Procellarum](https://en.wikipedia.org/wiki/Oceanus_Procellarum), covers about 4 millions km2.

These values are quite comparable with Large Igneous Provinces (LIPs) in terms of area, and are even one order of magnitude lower in terms of volume. From the [Encyclopedia of Volcanoes](https://doi.org/10.1016/B978-0-12-385938-9.00014-6):

> The composite Ontong-Java-Manihiki-Hikurangi plateau covers 3.5
> million km2 with an estimated volume 59-77 million
> km3. [...] The Kerguelen plateau in the southern Indian
> Ocean is the second largest LIP, covering 2.3 million km2
> with a volume of 15 million km3 [...] Not all LIPs are
> oceanic plateaus; for example, the North Atlantic volcanic province,
> derived from a hot spot presently centered beneath Iceland, has an
> area of 1.3 million km2 [...] Also notable are the Deccan
> traps in India (1.8 million km2/9.3 million
> km3).

If lunar maria seem that large from Earth, it's only because the Moon is small!

But **to know if lunar maria or LIPs would have looked like "glowing lava oceans shinning in the night", we need to look at emplacement rates rather than just areas and volumes**. From the same chapter, one can calculate LIP emplacement rates of ~3-13 km3 per year. It may seem quite low (for comparison, ocean ridges quietly produce ~20 km3 per year), but it is an average output rate over a few million years. As noted on [largeigneousprovinces.org](http://www.largeigneousprovinces.org/frontiers#melt), their might be pulses of magmatic activity, with peaks in production rate. This is exactly what's been inferred for lunar maria by [Wilson and Head (2017)](https://doi.org/10.1016/j.icarus.2015.12.039): even if the average output rate has been calculated at a very low 0.01 km3 per year, they found that some flows could have been emplaced with rates up to 106 m3s-1!

As to whether this would have been visible from space: define "from space"! From low Earth orbit like the ISS? From the Moon itself? :)

> **Comments:**
> **username_0**: Very interesting. When I say "seen from space" I imagine a view like the one from Geostationary satellites or the Moon. I know this would be clearly visible from the ISS since volcanic eruptions are usually visible, but I would like to know if LPIs would look like glowing red patches just as lunar marae looked a long time ago from Earth, or would the smoke block the view.  
> **username_1**: I guess it depends where the lava is emplaced. On barren land, where there is not much to burn, you could probably see lava glowing at night. But to witness a better show, you should probably go back in time to the Hadean and look at the magma ocean.  

---

### Answer by username_2 on 2019-11-09. Score: 0

Yes, there would have been seas of lava glowing in the night, but not as large as the lunar mare. The lunar mare were caused by asteroids punching through the then thin lunar crust and releasing a flood of magma from below, as well as producing some magma of their own from the heat of impact. There is no evidence of anything of that nature causing the Deccan Traps or the Siberian Traps. There must have been some smoke and haze from both super-eruptions, but not enough to hide them from an observer in space in the unlikely event that there were any. Much of the incinerated trees and other vegetation were covered by sheets of lava, and therefore could not release much smoke and fumes.

> **Comments:**
> **username_3**: In the case of the Siberian Traps, the rocks overlying the eruptions apparently contained large coal beds, which were set on fire by the eruptions.  Also, you seem to be assuming one continuous super-eruption, rather than an ongoing series of eruptions lasting from 30 thousand to a couple of million years: https://en.wikipedia.org/wiki/Deccan_Traps https://en.wikipedia.org/wiki/Siberian_Traps  
> **username_2**: How did the oxygen needed to support the combustion get through many metres of lava? Anyway, the question refers specifically to the Deccan Traps.  
> **username_0**: @username_3 If it were a series of eruptions instead of a continuous super-eruption what would the difference be in terms of the view from space? Less area covered with magma? Less spectacular than Lunar Mare?  
> **username_3**: @username_2: Presumably the same way it gets to underground coal fires today: https://en.wikipedia.org/wiki/Coal-seam_fire  (At the question doesn't ask about the Deccan Traps specifically, it asks about  large igneous provinces, using the Deccan Traps as an example.)  
> **username_3**: @username_0: I don't think it would be really spectacular at all.  It would be more like the  Hawai'ian volcanos (with a more fluid lava that doesn't pile up) spread over a large area: occasional eruptions, but mostly nothing.  Or maybe the Cascades: https://en.wikipedia.org/wiki/Cascade_Volcanoes  Lots of volcanic activity on a million-year timescale, yet only two significant eruptions in a very long human lifespan.  
> **username_0**: @username_3 Interesting, so when I see maps like these (https://www.eurekalert.org/multimedia/pub/web/99808_web.jpg) I shouldn't assume that the shaded area was entirely covered by lava in any particular time?  
> **username_3**: @username_0: Almost certainly not, though I'm far from being an expert.  It seems much more likely to have been built up by many eruptions over thousands or millions of years.  
> **username_0**: @username_3 Thank you so much, if you put this information as an answer I will select yours for sure.  

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