Magic Magma

It is well known that the interplay between volcanic and seismic zones is at work on the Reykjanes Peninsula. The peninsula is being pulled apart by the same forces as shape the Mid-Atlantic Ridge, and that is by definition a divergent effect. This causes the volcanic fissures to open up, being aligned from SW to NE. The dykes responsible for the eruptions have the same alignment, being in the same direction as the model used here. It is important that a mathematical formula can be used to calculate alignment of volcanic dykes, and it also adds to the credibility of the theory that convection rolls are found underneath the tectonic plates.

The seismic area of Reykjanes is bent, but the seismic faults are oriented N-S within the bent area. In addition, the Reykjanes seismic area extends from the South Icelandic Seismic Zone. These two seismic zones are therefore connected, and the connection point is also the point connecting two polygons of the convection rolls model. The Reykjanes seismic zone is formed due to compression of the area, perpendicular to the extension due to the divergent effect of the Mid-Atlantic Ridge. These pressure vectors are quite comparable to those of the South Iceland Seismic Zone.

What makes the Reykjanes Seismic Zone special is the fact that it is bent, making it possible to connect the Reykjanes Ridge and the South Iceland Seismic Zone. The two different forces therefore become compatible, resulting in a wholistic and logical drift system.

Superimposed blue line, showning mantle divisions, crosses the seismic and volcanic areas on the Reykjanes Peninsula, pointed out with an arrow on the map. Volcanic systems on the Reykjanes peninsula are shown in pink. The red lines indicate the tectonic plate boundary, where earthquakes are common. Geothermal areas are marked in yellow. Black lines indicate fissure swarms. Modelled division lines and the outlines of seismic zones are superimposed on a map base from ISOR.

The main active areas are found within the southern half of the bent seismic area, as it extends from the South Iceland Seismic Zone.

Comparing the model with the basics of the Oblique Rift Zone of Reykjanes does not explain the present activity to a full extent. On the other hand, it shows that the present event brings into light the combined effect of several factors, mainly the volcanic fissure swarms, the seismic zone, and the mantle rolls division lines.

A scientific approach to these three combined factors would be to compare them with petrological and seismic evidence, along with other information available about surface movements. That could answer many questions.

Not much is known about the source of this magma. It is only possible to trace its history with some degree of accuracy from the time when it is already being accumulated somewhere within the tectonic plate. The energy necessary to provide the magma is only found below the tectonic plate, and therefore the flow should be traced all the way down to the depth where convection can take place.

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The Ring of Fire on Equirectangular Map

May 15, 2024 Steingrimur Thorbjarnarson

Drawing the Ring of Fire on an equirectangular map, the main features fall into a narrow zone.

Two of the areas named on this map are often omitted when analysing the Ring of Fire, namely Yellowstone and Antarctica. With Antarctica included, the name ‘Ring of Fire’ can be taken literally, as a whole elliptical form is completed. Following up on this point, the circle is remarkably regular, with symmetric features, such as New Zealand, San Andreas Central Fault and Yellowstone on the minor axis. To be more precise, the San Andreas Fault is found where the inner ring crosses the minor axis, and Yellowstone is located where the outer ring crosses the same axis.

The basic idea by drawing the circle in this way, is the fact that subduction takes place exactly where equator crosses the outer ring within the Philippean Trench at the coast of Indonesia , and the Peru-Chile Trench crosses the same ring also on the equatorial line.

With a more detailed analysis, it can also be shown how the two rings follow the division lines drawn, representing the model introduced here. Examining the subduction zones one by one, a striking consistency between division lines and subduction zones is found.

Considerable research has been carried out regarding the subduction zones, and I like the work of Robert J. Stern a lot, as he has not only carried out a lot of measurements, but also contributed to the study of Earth’s history. Please read his article about the origin of subduction zones: https://speakingofgeoscience.org/2013/04/28/when-did-plate-tectonics-begin-on-earth-and-what-came-before/

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Volcanic Activity near Grindavík on the Reykjanes Peninsula

April 21, 2024January 18, 2025 Steingrimur Thorbjarnarson

The volcanic activity near Grindavík can be explained by referring to the interaction between a dyke forming within the volcanic zone, and magma from the dyke finding its way to the surface through earthquake faults. A seismic zone creats a weakness of the crust within the area. The orientation of the dyke is quite different from that of the earthquake faults. According to calculations the dyke is oriented about N43°E, and the earthquake faults trend is directly N-S. Real circumstances are not quite so simple, because the upper most manifestations of earthquake faults are en échelon arranged, divided into smaller systems with NE-SW trend. The dyke, when meeting with the earthquake faults, also bends, or follows the N-S trend near the eruption site. As I have been exploring the possibility that convection rolls are found withn the asthenosphere, and mapping the division lines between them, it is interesting to compare those lines with the conditions at the eruption site. Two downwelling lines of the lower parts of the asthenosphere are found directly below the eruption site itself. To understand the situation better, we should have a look at a map showing this:

This shows how the black division line crosses the Reykjanes Seismic Zone shown with red parallel lines. It is tempting to assume that the origin of magma can be traced to those two division lines directly below the eruption site. Another possibility is that the magma is originated from the upper most division line, alinged NE-SW, found slightly west of the eruption site, flowing at first under the crust along the NW-SE aligned line until it reaches the eruption site area. Then it ascends into magma chambers and finally to the surface.

This site shows many different situations where convection rolls system and real circumstances fit together. This is of course a very good example. The fact that the three eruptions along the dyke which formed under Fagradalsfjall, and the four eruption that have already taken place along the dyke forming at the side of Sundshnúkur have the same petrological origin is consistent with this.

This is an explanation built on many years of research. I have taken part in a series of conferences and meetings, publishing papers where the scientific papers pointing in this direction are cited. I also took part in mapping the South Iceland Seismic Zone, giving me the feeling of how the seismic area of Reykjanes works, as those two systems are connected end-to-end.

To explain the heat flow within the Earth, from radioactivity to eruption, is not easy, but it can be done. This eruption deserves much attention, and among the countless examples shown here, this one of those literally to the point.

The two other seismic zones of West Iceland (BTZ) and South Iceland (SISZ) are added to show how likely it is that the polygons surrounding distinct areas of Iceland really exist. To form a seismic area, pressure is nedded. The faults are all N-S oriented, so regularity is needed. The parallel faults are found side by side in E-W direction, having distinct endpoints, so the area is limited. The only solution for an outer framework is a polygon, exactly as drawn on the map here above. The division lines between convection rolls coincide with this enevitable polygonal shape surrounding the seismic zones. Therefore, it makes sense that the division lines are responsible for shaping the polygons in the first place. It is all about logic.

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The San Andreas Fault and Yellowstone Caldera within the Ring of Fire?

February 20, 2024February 21, 2024 Steingrimur Thorbjarnarson

The San Andreas Fault and Yellowstone Caldera are shown on this map:

Those famous sites have a comparable position compared with the so-called Ring of Fire as drawn here. Most subduction zones around the Pacific fit into a tight elliptical form centered at 6°S and 155°E with eccentricity = 1.4. It passes equator at the coast of Indonesia and South America. This is drawn on an equirectangular map, used for the mantle convection rolls model. The major axis is tilted 40° and the minor 50°. The Central San Andreas Fault and Yellowstone are thereby found at the inner and outer limits of this mathematical version of the Ring of Fire. Those are probably the most famous geological features of the United States, along with the Grand Canyon. There are explanations available for this consistency, as shown here: https://pangea.stanford.edu/ERE/db/GeoConf/papers/SGW/2024/Thorbjarnarson.pdf

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Dyke Formation at the Reykjanes Peninsula near Grindavik in 2023

November 11, 2023November 11, 2023 Steingrimur Thorbjarnarson

The formation of a dyke near the town of Grindavik in Iceland was quite sudden. First, a sill did form at the depth of approximately 5 km. Then magma started to make its way upwards, forming a dyke reminding us of what has happened in the vicinity of Fagradalsfjall three times during the last three years.

The dyke can be compared to the convection rolls model, and two lines cross the center of the dyke. The lines are blue, standing for down-welling. Down-welling can provide magma just as up-welling. The southern part of the dyke is aligned parallel to the convection rolls pattern, but the northern half is more affected by the earthquake zone, where NS oriented earthquake faults are a dominant factor within the brittle part of the crust.

The inserted maps are from ISOR (for volcanic systems) and the Icelandic Met Office (dyke formation indicated by earthquake epicenters). The main drawing is superimposed on a map from the National Land Survey. The main divison line is based on present tectonic drift vectors.

A section of the layers, represented by red and blue lines, is shown here below. This was prepared to show the location of the Fagradalsfjall eruptions, but they were so close to the site of the formation of the dyke presently ascending, so it is also used here as a representation: