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20 votes

Why is basalt denser than granite?

Magmas have a wide range of chemical (and mineralogical) compositions. Basalts come from mafic magmas (they used to be called "basic" magmas), while granites come from felsic magmas (used to ...
Jean-Marie Prival's user avatar
6 votes
Accepted

How long does a stratovolcano live?

I was going to write an answer based on a few known examples (see my previous comment), but a few examples are not necessarily statistically representative. So I checked good old Encyclopedia of ...
Jean-Marie Prival's user avatar
4 votes
Accepted

How did Mt. Etna get so good at blowing smoke rings? Is this new?

Is it new? No! It's been witnessed for at least a few centuries (probably more, but we don't have records). According to Fuentes (2014): Ignazio Sorrentino, secular priest of Torre del Greco and a ...
Jean-Marie Prival's user avatar
3 votes
Accepted

How long will red hot lava from the Sundhnúkur eruption in Iceland be visible?

I have experienced a similar situation two years ago. I visited the site of the 2021 Fagradalsfjall eruption on November 18, 2021, exactly two months after the last emission of lava (and one month ...
Jean-Marie Prival's user avatar
3 votes

Can a cryovolcanic eruption be as powerful as a normal volcanic eruption?

Here is a recent preprint about a possible super cryovolcano on Pluto. In this study, Cruikshank et al. analyzed the morphology and composition of Kiladze, a wide (~44 km in diameter) depression at ...
Jean-Marie Prival's user avatar
3 votes

Why are all lower mantle plumes under oceans?

Mantle plumes are part of the movement driving plate tectonics. These movements push continental plates apart making oceans. It's not that they occur in oceans, they cause oceans. As pointed out in ...
Josh King's user avatar
  • 321
2 votes
Accepted

What is the pitch and roll in a tiltmeter sensor?

It's simply the measurement of incline in the x and y horizontal directions: Roll is the angle created by the slope $\frac z y$ Pitch is the angle created by the slope $\frac z x$ A tilt meter and ...
Stevan V. Saban's user avatar
2 votes
Accepted

How can you infer the burning degree (Celcius etc) of a wood from a heat effected specimen?

There has been a recent study about this: Pensa et al. (2023) used charcoal samples found in the deposits of the 79 CE eruption of Mount Vesuvius to infer the temperature of its pyroclastic density ...
Jean-Marie Prival's user avatar
2 votes

Is the 30,000 HYDRON COLLIDERS around this planet being used to manipulate Earth's magnetic fields to create eruptions, earthquakes,ECT

Hadron colliders are expensive to construct and operate. As a consequence only five have been constructed, not 30 000. The construction cost of the Large Hadron Collider was 4.332 billion Swiss Francs....
Fred's user avatar
  • 24.7k
1 vote

Are there any specific examples of overlapping impact and volcanic craters on Earth?

Yes in fact it may be fairly common for larger impact craters since they fracture and weakend the crust. Plus the impact itself will melt rock meaning by definition each large impact crater has som ...
John's user avatar
  • 6,966
1 vote

What determines when the end of a volcanic eruption will happen?

This is a partial answer to the "how can it be predicted" part of the question. A new paper (Duputel et al., 2023) shows how Very-Long-Period (VLP) seismic events can be used to infer the ...
Jean-Marie Prival's user avatar
1 vote

Eruptive fissures in Hawaii associated with Kilauea; what are they? What is really happening?

Looking the diagram you supplied in the question, at the bottom there is graphical representation of a cross section through a volcano. The structure in red represents the magma conduits. Magma is ...
Fred's user avatar
  • 24.7k

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