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Reykjanes Eruption – where is the origin?

Steingrimur Thorbjarnarson

The tenth eruption on the Reykjanes Peninsula started suddenly on the Sundhnúkagígar fissure. All those eruptions are thought to be connected and considered to be one volcanic event, based on rather constant flow of magma from the interior. The model used here adds an explanation of the geophysical settings of the deep roots of the volcanic site. Two convection rolls division lines coincide under the point where the magma ascends. The lines cross the outer limits of the seismic zone at this location, providing a weakness in the crust.

Convection rolls model and site of ascending magma at Reykjanes Peninsula.

To understand how the system works according to the model, this drawning can be studied. The two layeres, with division lines between convection rolls found under the point of ascending magma, are marked here as source layer A and source layer B. Layer A is found at the depth of about 260 km, and layer B at 530 km depth (530-670 km). This means that magma of different types should be found, both from layer A and B. Besides that, the hot magma from below does partially melt the ductile part of the tectonic plate (commonly referred to as upper mantle found below the brittle crust).

The petrology of the lava should therefore be compared with these modelled preconditions of the eruptions. The three eruptions on Fagradalsfjall volcano and the seven eruptions on the Sundhnúkar fissure are originated from the same source, according to the findings in the article: The Fagradalsfjall and Sundhnúkur Fires of 2021–2024: A single magma reservoir under the Reykjanes Peninsula, Iceland? ( https://www.researchgate.net/publication/381756298_The_Fagradalsfjall_and_Sundhnukur_Fires_of_2021-2024_A_single_magma_reservoir_under_the_Reykjanes_Peninsula_Iceland

The authors of the article (Valentin R. Troll. Frances M. Deegan, Thor Thordarson, Ari Tryggvason, Lukáš Krmíček, William M. Moreland, Björn Lund, Ilya N. Bindeman,
Ármann Höskuldsson and James M. D. Day), come to this conclusion: “Whole rock and mineral geochemical data show that the
2023 SVL eruption produced lava compositions that, for the most
part, continue the trends established by the lavas of the late 2021 to
2023 Fagradalsfjall Fires (Figures 4 and 5). A first-order observation
is therefore that all of the recent FVL and SVL magmas are derived
from a similar magma source (excluding perhaps the early parts of
the 2021 Geldingadalir eruption), or a similar combination of sources,
which are different to the source(s) of previous magmas erupted on
the RP…”

Considering that, according to the model of convection rolls, it is quite likely that the uppermost division lines, oriented SW-NE, often provide magma from the mantle. This time it is probably not the case, as it seems likely that the source is from those deeper layers, because the relevant division lines are found exactly under the magma source location, which might explain different composition of the lava samples considered in the said article.

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The Eastern and Western Outposts of Icelandic Volcanoes – Snæfell and Snæfellsjökull

Steingrimur Thorbjarnarson

The two outposts of Icelandic volcanoes are both stratovolcanoes. They are outside the main volcanic zones, and do not fit with the most simplified version of Icelandic geology. One is too far to the west, the other too far to the east to match well with our most basic ideas about how Iceland is divided into its North American part and Eurasian part. The convection rolls model considered on this webpage is of course different, and according to the pattern emerging from the division lines between convection rolls, the positions become understandable. If there were no such reasons, such as convection rolls, the coincidence that those two mountains are exactly on the same latitude could not be explained. Of course it is easy just to ignore things like that, but these two volcanoes are both found on division lines between convection rolls, in a mirrored way.

It should also be mentioned that the distance from those two volcanoes to the main division line of the lower mantle, is exactly the same, when compared with the N-S axis of Hekla volcano. That means, of course, that the two Snæffells (Snæfellsjökull and Snæfell) are equidistant from Hekla. Such a coincidence can of course also be ignored, but according to this system of convection rolls, it is explainable, because Hekla does form on important crossings within the convection rolls division lines pattern. Different layers all have division lines under Hekla, four different convecting layers! The location of Hekla is therefore no coincidence, and the uppermost layer of mantle convection is upwelling underneath Hekla, making the location even more understandable. All over the world, countless similar patterns can be found, all in harmony with the convection rolls.

Snæfellsjökull, November 15th 2024.

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The Outside Position of Öræfajökull Volcano

Steingrimur Thorbjarnarson

The highest volcano of Iceland is far east of the main volcanic zones. The position is easy to understand when looking at the convection rolls system map. The top of the mountain is above the crossings of the four sets of upper convection rolls found underneath it. Besides that, Öræfajökull is found as a continuation to the south of the North Volcanic Zone (NVZ), and on the same line as the South Iceland Seismic Zone (SISZ) on the 64th parallel.

All other volcanic sites in Iceland can be analysed in a similar way. The Convection Rolls Model is a very effective tool which can be used to better understand the framework of volcanic, seismic and geothermal areas everywhere in the world.

The three papers describe the whole system and its relevance to geological circumstances: Basic description: https://pangea.stanford.edu/ERE/db/WGC/papers/WGC/2020/13040.pdf?t=1612656487

Divergent boundaries: https://pangea.stanford.edu/ERE/db/GeoConf/papers/SGW/2023/Thorbjarnarson.pdf,

Convergent boundaries: https://pangea.stanford.edu/ERE/db/GeoConf/papers/SGW/2024/Thorbjarnarson.pdf.

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Mantle Convection or Mantle Plumes?

Steingrimur Thorbjarnarson

In Iceland, many people think that a mantle plume is responsible for volcanic activity. The plume is thought to be centered around the western part of Vatnajökull. All the same Gilliam R. Foulger came to the conclusion that a plume, of the kind imaged, can not exist. https://www.mantleplumes.org/WebDocuments/P%5E2Rev_Harangi.pdf

In fact, Foulger does find a proof that this kind of plume does not exist. The relevant data shows that no continuous hot mass is ascending under Iceland. Therefore we should stop imaging this plume and continue the search for the inner structure of Earth with measurements and calculations according to the physical properties of the mantle.

Convection does, on the other hand, fit all available data. Experiments show that mantle material forms convection rolls under those circumstances expected to prevail within the Earth. Testing it, by making a model with convection rolls filling the measured layers, shows remarkable results. Features on Earth, both divergent and convergent, fit to the convection rolls underneath.

Now, when this has been solved, it is very easy to proceed with research programs, further improving our understanding of the inner structure of the Earth. First, we have to admit that the former idea about mantle plumes is wrong. A model of a regular system of convection rolls is what brings us farther ahead. Luckily, we have the scientific method to assist us with our work. By having a foundation of physics, measurements, mapping, calculations and logical thinking, besides being able to communicate freely, these steps forwards can be made.

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The Ring of Fire is Circular for a Reason

Steingrimur Thorbjarnarson

The Ring of Fire is in fact circular, and 15 main parts of it are pointed out on the map below. The shape of the Ring of Fire is indeed circular, because the volcanoes of Antarctica fit into the area in between two elliptical shapes drawn with its outer limits marked by two points on equator, at the coast of Indonesia and South America, respectively. The two points are characterized by subduction zones. Let us examine this most active area in the World, in terms of seismic and volcanic activity. Looking at the arrows and lines, it is easy to understand how reality fits with the model.

  1. The first point pointed out on the map is the subduction zone of the Philippian Plate at the coast of Indonesia. It is a triple point where both the Philippian Plate and Pacific Plate meet with Indonesia. The South American counterpart on the equator is found exactly 150° west of this point. It fits to the width of five large-scale convection rolls.
  2. The Challenger Deep is the lowest point on Earth. It coincides with the inner margin of the Ring of Fire as drawn here. The convection rolls of different layers coincide with the area.
  3. Honshu Island of Japan clearly coincides with the convection rolls model, and is also within the elliptical area of the Ring of Fire.
  4. Kamchatka has been examined in other posts here, and the volcanic zone follows the alignment of convection rolls. It falls into the elliptical zone in similar way as Honshu Island.
  5. The Aleutian Islands form an arc from east to west. The easternmost part seems to follow the path of a division line between convection rolls. The central part crosses a large-scale convection roll, and the western part connects with Kamchatka. This arrangement indicates why most areas fall within the form of two ellipses, with short segments originated from convection rolls division lines.
  6. Cascadia is mentioned in two of the main articles found on this site. Subduction and divergent boundaries are found in the area.
  7. The Yellowstone National Pard is specially interesting, because usually it is not mentioned as a part of the Ring of Fire. As presented here, it is strongly related to it in two different ways. First, it is found on the circular line connecting the two points on equator. Second, it is found on the straight line of the mathematical minor of the elliptical forms, in continuation of the Central San Andreas Fault. New Zealand is on the other side of the Ring of Fire, where the other end of the said minor is found. With a little bit of logic at hand, it is then possible to analyze what kind of stress point this is, and thereby what causes the extraordinary activity level of Yellowstone Park. The usual saying, that it is a hot spot, is not enough. Of course it is a hot spot. But the settings of the Ring of Fire do indicate a complex origin of the volcanic and geothermal activity found there.
  8. The San Andreas Fault is found on the inner margin of the Ring of Fire and is used here to find that inner margin. The inner elliptical shape is not as clearly marked as the outer ring found by intersecting two obvious points on equator.
  9. Central America has some interesting features, especially volcanic activity where petrological evidence can be used to examine the explanatory value of the convection rolls model.
  10. This point has already been mentioned as the counterpart of point 1.
  11. The Galapagos Islands are found on equator in between the elliptical forms of the Ring of Fire.
  12. The Andean Mountains fit very well to both Convection Rolls Model, and the modelled Ring of Fire.
  13. The volcanoes of Antarctica are more seldom mentioned in geological literature than many others, but they are of course just as important for geological studies. The location of those volcanoes fits exactly into the circle. It indicates that the circularity is actually a precondition of the subduction zones system.
  14. New Zealand has been mentioned as a counterpart of San Andreas and Yellowstone, being on the mathematical minor of the circle.
  15.  The Australian Mountains are not mentioned as a part of the Ring of Fire, but they are found within its realms, and it is said that they are still gradually growing higher.

In this way, it can be explained that the Ring of Fire is a wholistic area. It is correct to describe it as a ring, and should be studied more extensively .

The circular form of the Ring of Fire.