Questions tagged [volcanology]

The properties and behaviour of volcanoes, from the genesis of magmas to their ascent and emission at the surface of the Earth (or other planetary environments).

Filter by
Sorted by
Tagged with
1
vote
0answers
26 views

What is the most current thinking on the amount of heat transferred into the oceans from underwater thermal vents and volcanoes?

My understanding is that with the relatively recent discovery of many more volcanoes on the Mid-Atlantic Ocean Ridge (and perhaps other ocean ridges) and more deep trenches with thermal vents, that ...
21
votes
0answers
718 views

How are Mauna Loa $\ce{CO2}$ monthly trends computed?

The problem I am trying to figure out how $\ce{CO2}$ concentration trends are computed in the data provided by the Earth Systems Research Laboratory Mauna Loa Observatory. The data contains monthly ...
0
votes
0answers
41 views

Ranking volcanic rocks influence to geothermal suitability?

I am not a geologist/geology student but I want to quickly know the influence of volcanic rock type to geothermal suitability. I have read read some journals and online articles but it seems there are ...
22
votes
3answers
22k views

Where can obsidian be found?

Where is obsidian found? Is it typically found on the surface or underground? If underground, how far under (meters or feet would be perfect)? Also, is it found everywhere on Earth, or just in areas ...
1
vote
5answers
125 views

It is possible to send a probe deep within the Earth?

The deepest borehole ever drilled is just 12km. Consider this as a possibility. A small self-propelled probe is created, its approximately the size of a football, and is very strong, made of materials ...
1
vote
2answers
63 views

Is it possible for an active volcano to become less violent over time?

Suppose a violent, dangerous composite volcano whose eruptions destroy the nearby countryside exists. Would it be possible for this volcano to change such that future eruptions are less violent, and ...
7
votes
3answers
202 views

Is the momentum of a volcano's high-velocity ejecta mostly due to expanding gas?

When I was very young I was always amazed that water didn't come shooting up out of the first ice-fishing hole of the season, due to the weight of all the ice. It doesn't, because the weight of the ...
2
votes
1answer
160 views

How many extreme shifts in climate has Earth gone through in its existence?

As the Earth formed, it went through cycles of essentially hotter and colder periods. Extremely volcanic times and ice ages, in feedback loops contributing to one another. CO2 swinging from high to ...
26
votes
3answers
5k views

Why is Olympus Mons the largest volcano in the whole solar system?

Why is it that the volcanoes found in the Tharsis Montes region near the Martian equator, (one of which is Olympus Mons) so much larger than those found on Earth. In comparison, Hawaii's Mauna Loa, ...
1
vote
1answer
44 views

What happens when a mid-ocean ridge sub-ducts underneath continental crust?

I'm aware that oceanic crust always sub-ducts to continental crust, but surely the geologic forces pushing the ridge apart in the first place isn't just going to turn off, right? Any answers would be ...
2
votes
0answers
29 views

What if Pinatubo's eruption in 1991 had been followed by a La Niña rather than an El Niño?

If there had been a La Niña rather than an El Niño in 1991-92, would the sulfur aerosol veil caused by the release of 17-20 megatons of sulfur dioxide during the Pinatubo eruption of June 1991 have ...
4
votes
1answer
78 views

Frost in trees in the middle of summer (of 536)

It was so cold that frost formed inside trees in the middle of summer. Traces of this have been found in Russia, among other places. It is very rare for trees to freeze internally during the summer. ...
5
votes
1answer
92 views

Employment of Volcanologists and Petrologists

What industries or government departments hire volcanologists and igneous petrologists/geochemists in the United States?
13
votes
1answer
580 views

Why would volcano eruption cause cardiac arrest?

Following recent eruption of Mt Ontake and the sad news of over 30 people found in 'cardiac arrest', why would the eruption cause it? My initial thought would be that the cause of death would ...
4
votes
2answers
1k views

Causes of fluctuations in atmospheric oxygen in past 300 Mya

I have two questions based on the history of atmospheric oxygen levels depicted below. Source: https://commons.wikimedia.org/wiki/File:Sauerstoffgehalt-1000mj2.png. The notes below the chart explain ...
1
vote
2answers
114 views

Why aren't there ultra acid igneous rocks?

In my study, I found that in volcanoes when the magma is going up it formed different types of rocks. There are basic, acidic and ultrabasic. My question is why isn't there ultra acid igneous rocks ...
18
votes
3answers
3k views

Is the magma in one volcano different from the magma in every other volcano?

First off, a confession: I'm asking this question because of The Lord of the Rings. If you're not aware already, in the story, a magical ring can only be destroyed in a specific volcano. The reason ...
20
votes
3answers
1k views

Why does Volcano Lightning occur?

There are many pictures I've seen of lightning coming out of the plume of smoke caused by a volcano (Often called 'Volcano Lightning'). Example: Why does this happen?
1
vote
1answer
125 views

How does fertile soil reach newborn volcanic islands?

When a volcanic island first surfaces, I assume no vegetation can grow, as it probably only consists of volcanic rock. How would a volcanic island like Iceland that is far from any continent grow to ...
4
votes
1answer
2k views

Why do human populations concentrate near fault lines, volcanoes, etc.?

I've noticed that many places with large populations tend to be prime zones for natural disaster. Examples: Silicon Valley = earthquakes, Houston = hurricanes and floods, Japan = tsunamis and ...
6
votes
2answers
278 views

Geomorphological feature identification

I was studying a satellite map of Iceland and came across an interesting, but unnamed feature located between Vatnajökull glacier and Trölladyngja volcano (between 64°50'35"N, 17°11'21"W and 64°48'33"...
2
votes
0answers
191 views

How Big Were the Siberian Traps ORIGINALLY?

252 million years ago, Siberia was subject to a mass series of flood basalt eruptions, creating a large igneous province called the Siberian Traps. Today, it measures three million square miles in ...
0
votes
0answers
89 views

What initiates the plumes which create oceanic hot spots? [duplicate]

What causes the large and very long lasting magma plumes which rise up from the mantle and create a hot spot such as the ones which built the island chains of Hawaii and Galapagos? The volcanic ...
1
vote
0answers
60 views

Did people trigger the White Island 2019 eruption? [duplicate]

I am writing an essay about White Island’s 2019 eruption, and I need to know if the eruption was directly triggered by people. Is it possible that it was? Whether it being quarrying, too much tourism ...
20
votes
3answers
5k views

Why don't scientists use fire entry suits to study volcanoes?

It seems like the only personal protective equipment (PPE) that volcanologists use are aluminized suits that don't provide any protection from direct contact with lava, making an unexpected splash ...
3
votes
2answers
102 views

What is the difference between mobile & molten rock?

In the book Fundamentals of Geomorphology (Routledge Fundamentals of Physical Geography) by Richard John Huggett there is a sentence " Intruded rocks, which must be mobile but not necessarily molten,...
0
votes
1answer
142 views

How Can Adjacent Parts of an Oceanic Plate be Subducted in Different Directions?

It is claimed by some that the reason for gaps in chains of volcanoes generated by plate subduction is that some parts of the plate dive deep into the mantle and generate magma plumes, while other ...
7
votes
2answers
80 views

Why do (some) silicic bodies behave effusively instead behaving explosively as in common?

We encounter dacitic/rhyolitic melts generally in explosive volcanic events. But some of them behave as effusive dome flow. Why do some silicic bodies behave effusively?
14
votes
2answers
255 views

How did this rock dome (pictured) form?

I saw this rock formation near Hveravellir, Iceland. It is probably of volcanic origin and looks like a dome. It is nearly symmetric and appears to consist of hardened lava maybe, with several very ...
12
votes
2answers
446 views

Did the Geothermal Power Plant contribute to Pahoa's Lava Fissures?

There was lava in the area near the wells that the Puna Geothermal Venture facility created. The plant has nine wells that run as deep as 8,000 feet, according to Wil Okabe, managing director for ...
1
vote
3answers
1k views

Lava and Magma, Meteor and Meteorite--What's the Difference?

Some features of Earth (and beyond) have been bugging me for quite some time. When molten rock is beneath the surface, it's called "magma". Above the surface, it is called "lava". When a bolide is ...
6
votes
1answer
340 views

How big a risk is Mount Vesuvius for the local population?

How much of a risk does Mount Vesuvius pose for the population of the surrounding area?
8
votes
3answers
1k views

Gaps in locations of volcanos (Peru & Chile)

The figure below is taken from Reath, K. et al. (2019) A couple of things can be seen from this representation Volcanism seems to be strongly correlated with subduction zones, in this case the Nazca ...
11
votes
2answers
233 views

Would a volcanic winter trigger an oceanic “spring”?

There is large amounts of observations supporting the effects of volcanic eruptions on climate: A long term subtle warming effect due to $\small\mathsf{CO_2}$ and a short term, but more intense ...
1
vote
1answer
154 views

How likely is Earth to naturally reverse climate change in the next 2 decades?

A new decade question: given that the “mini ice ages” were triggered by volcanic activity, how likely is it that we will experience similar levels of volcanic activity over the next 20 years? In ...
5
votes
2answers
89 views

Coral Reef and Volcanic Islands

I have two questions regarding coral reef and volcanic islands. When a new volcanic island is formed, how much time generaly passes before a coral reef starts to form around the island? Another ...
3
votes
1answer
70 views

What determines the scale of columnar jointing?

What physical parameters determine the scale of columnar jointing? What makes the columns thinner or thicker? What makes them taller or shorter? What causes the variation in a given site? What ...
7
votes
3answers
570 views

Why do some earthquakes and volcanoes occur within plates?

I know that volcanoes and earthquakes occur on plate margins. But, do some of them also occur within plates?
2
votes
1answer
138 views

Could Rumblings From Plutons be as Ominous as Rumblings From Volcanoes?

Mount Kinabalu in North Borneo is a 10 million year old pluton. A pluton is a magma plume from the mantle which was not able to reach the surface and erupt as a volcano, but solidified underground and ...
2
votes
2answers
110 views

Large Igneous Provinces are like Lunar Mare?

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 ...
4
votes
4answers
575 views

Are the cores of every mountain range igneous?

Every volcano is a mountain, but not every mountain is a volcano. Still, it strikes me that--at least for the mountain ranges I can think of in this moment--they all seem to have igneous cores. Is ...
10
votes
2answers
276 views

What would the precursors to a repeated Lake Toba super eruption?

Lake Toba, Indonesia is a supervolcano which was the site of a massive supervolcanic eruption estimated at VEI 8 that occurred 69,000 to 77,000 years ago, representing a climate-changing event. It ...
6
votes
2answers
160 views

How is climate change today different than the climate change that ended the ice age(s)?

Someone I know posted a question about climate change that I do not know how to answer. While I do believe (for lack of better word) in climate change, I do not know how to answer this persons ...
0
votes
1answer
104 views

Q: Is the crust getting thinner or is the mantle getting smaller

Volcanoes spit out magma onto the surface of the crust or crevices on the surface, but the magma comes (in effect) from the mantle right? If that's the case, isn't the mantle turning into the crust by ...
1
vote
0answers
18 views

Do overlying strata subside before/during volcanic exogenous dome emplacement?

Is subsidence (graben faulting) expected before/during a volcanic exogenous dome emplacement on the surrounding strata?
2
votes
2answers
2k views

How do quartz veins form?

Is there an association with thrust fault or dormant volcanos and quartz veins? Where are quartz veins likely to occur in nature and how are the formed? Is it possible to identify these veins from ...
1
vote
0answers
52 views

Interpreting an outcrop of a thick pure silica bed in a volcanic setting

How can a nearly pure silica bed with 250 m x 50 m x 1.5 m dimensions be interpreted in a volcanic/pyroclastic setting? Here is a photo of it.
4
votes
1answer
106 views

Where are these volcanos as seen in this space tweet?

In his recent tweet from the International Space Station as it's current Mission 56 Commander, NASA astronaut Andrew J. Feustel says: This is #Indonesia as viewed from the @Space_Station. With the ...
3
votes
1answer
175 views

What kind of lava tube feature is Cleopatra's Grave?

Cleopatra's Grave is a natural feature inside (warning: PDF) Catacombs Cave in Lava Beds National Monument near Modoc, California. Source: LookBeforeYouLive My apologies, as this image is somehow in ...

1
2 3 4 5