16
votes
What is the most important source of natural gas? Coal, oil or other?
The most important source of natural gas is natural gas. This is why it is called natural. It is not "made" from oil or coal.
Natural gas forms by decomposition of organic material. Whether the ...
- 22.9k
11
votes
Accepted
Is there likely to be coal under the Sahara?
The older rocks underlying the Sahara
are mostly granite, schist, or gneiss, all mixtures of igneous and metamorphic rocks forged deep beneath the surface
This stable mass of rock has been covered ...
- 23.2k
8
votes
Accepted
Could diamonds be formed from coal?
Craters actually can be identified by formation of high-pressure materials such as diamonds or stishovites and coesites (varieties of shocked quartz). A good example of this is the Popigai crater in ...
- 549
8
votes
Petroleum and coal formation
Coal, oil and gas can be found anywhere on Earth: on land and on sea.
The Japanese once mined coal from beneath the sea floor, using Hashima Island as the base of operations. The island is only 6.3 ...
- 23.2k
7
votes
Is there a risk with putting out smouldering underground coal reserves?
There isn't a risk to putting it out other than the attempt failing, it is just impractical to do so once a large coal vein catches fire. You can read more about the Centralia, PA coal fire on ...
- 14k
6
votes
Why is coal classified as a sedimentary rock?
I'm not sure why you are including shale in your question, unless you are referring to carbonaceous shale, which in not coal, but shale with carbon throughout the matrix of the shale.
Shale is an ...
- 23.2k
5
votes
What is the most important source of natural gas? Coal, oil or other?
A significant part of the natural gas used around the world today comes from oil fields.
On top of the oil is a layer of natural gas, and in the crude oil is dissolved natural gas. This will be ...
- 1,860
4
votes
Coal self-heating and spontaneous combustion, how does this happen?
Reference [6] under that Wikipedia article on spontaneous combustion gives you some answers:
"The Fire Below: Spontaneous Combustion In Coal". DOE/EH-0320, Issue No. 93-4. US Department of Energy. ...
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4
votes
Coal self-heating and spontaneous combustion, how does this happen?
Sulphur/sulphides in coal may be one of the causes of self combustion.
A slight diversion - in some metal sulphide mines, such as copper, at high level of sulphides in the ore, the sulphides can ...
- 23.2k
4
votes
Coal fires affecting seismic activity, and also volcanoes
I'm assuming you mean underground fires within coal seams whether they are caused naturally or through human neglect or error.
Regarding the possibility of them "triggering volcanic eruptions by ...
- 23.2k
4
votes
Open Mining facility/operation GIS data
For the US, there are several sources:
Mineral Resources Data System (MRDS)
MRDS is a collection of reports describing metallic and nonmetallic mineral resources throughout the world. Included are ...
- 5,939
3
votes
What is oldest known coal source?
The first coal deposits were laid during the Carboniferous period, between 358.9 million years ago and 298.9 million years ago.
Within this period, the early Mississippian period from 358.9 to 346.7 ...
- 23.2k
3
votes
Coal self-heating and spontaneous combustion, how does this happen?
Coal and other organics like wood and straw decompose when exposed to oxygen, that decomposition is an exothermic oxidation reaction so it heats the material around it which accelerates the ...
- 4,250
3
votes
Is there a risk with putting out smouldering underground coal reserves?
Nice idea but the practicalities are impossible. There are parts of Indonesia which have out-of-control peat and coal fires which have been raging for years, and even decades, despite those areas ...
- 14.1k
3
votes
What is the climate footprint of burning lignite coal - once you account for the athmosheric cooling effect of sulfur dioxide?
Sulfur dioxide, as such, does not cool the atmosphere. The cooling comes about when the sulfur dioxide is oxidized in the presence of moisture to produce dilute sulfuric acid in the form of aerosol; ...
- 3,321
2
votes
What is the most important source of natural gas? Coal, oil or other?
The most important factor for petroleum becoming gas isn't a substance, it's temperature and pressure. Most reservoirs have varying degrees of both; the T&P dictates how much of each will form. ...
- 495
2
votes
When is the carbon stored in fossil fuels released back to the atmosphere under natural conditions?
What natural processes do you contemplate would result in fossilized carbon (coal, oil or gas) being returned to the atmosphere?
Judging from the picture below,
Some coal deposits are between 250 Ma &...
- 23.2k
2
votes
Can Hydrocarbons be beneficial?
Generally, hydrocarbon fossil fuels cannot be regarded as being beneficial to life on Earth. Even human usage cannot be considered beneficial overall. Energy can be derived from fossil fuels but there ...
- 23.2k
2
votes
Why is coal classified as a sedimentary rock?
Rocks are not necessarily made out of minerals. Yes, most of them are but it's not a requirement. Also, not every collection of minerals is a rock. For instance, sand is not a rock.
This is not ...
- 22.9k
2
votes
Coal self-heating and spontaneous combustion, how does this happen?
Coal, which is essentially pure carbon, slowly oxidizes, it is the same reaction as it burning just much slower.
This is the major source of heat for self-heating of coal.
Many things that will burn ...
- 6,708
1
vote
Where did all the CO₂ come from that was deposited as coal during the Carboniferous?
Prior to the carboniferous period, and until the human industrial era, the majority of carbon dioxide in the atmosphere was due to volcanoes.
For billions of years, geological processes like ...
- 23.2k
1
vote
What is the origin of cleating in coal?
Short answer, its not well studied. It is most likely a diagenic process just because that is the source of most fractures in rock.
https://www.sciencedirect.com/science/article/abs/pii/...
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1
vote
Roughly how much Co2 is generated per kWh of electricity generated
About 900 grammes of CO2 for each 1kWh of electricity.
There is some variation: very modern super-critical coal plants can be lower. But 900g is a reasonable central estimate.
Note that that's just ...
- 4,090
1
vote
Petroleum and coal formation
There's no significant difference in distribution beneath land and sea. Recovery is all about accessibility. There's plenty of coal under the sea, but we just can't get at it - fortunately! To avoid ...
- 14.1k
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