How do we know that fossil fuels...?

Question

like coal and oil take millions of years to form?

just wondering

Answer 1

From the depth under the earth's crust where they are and what animals fossils are found in that area.   Also that contients drifted and some areas that are cold now were warm before (like canada) and that rate of drift is measureable.  Finally carbon dating of it and surround rocks helps

There are theories that some types of oil are formed chemically and not bioligiclaly but I don't think most people follow that but there are scientists studying it, this would be much faster

Answer 2

Fossil fuels are all made from fossilized plants, the plants absorb carbon dioxide while they are alive, but not when they are dead.  A certain percentage of the carbon dioxide in the atmosphere at all times contains an isotope, or radioactive, type of carbon.  When the plant dies, this isotope is locked into its cells.  A certain amount of the isotope goes away and become normal carbon over time, although it takes a very long time for it all to go away.  By analyzing the sample of coal, oil, etc. and measuring how much of this radioactive carbon is still present you can figure out how old it is.  Do a google search for radiocarbon dating if you want to learn some more.

Edit:

Look up Argon dating, which is able to go much further back than C-14 dating and basically works the same way.   I'm glad you looked it up and noticed that I had misspoke, but I wouldn't be so quick to call people ignorant, you're the one who asked the question in the first place and we're just trying to help you out.   Ignorant would have been people answering that the earth is only 10,00 years old so there is no way the fossil fuels are millions of years old.

Answer 3

Scientist can find out how long something has been around by examining it and testing it :)

Answer 4

You are correct about carbon dating.   To date older things, other radioactive isotopes found in rock layers can be used.   A name for this is radiometric dating, and is fairly accurate for millions of years.  Do some internet research on the topic.

Answer 5

Mostly by geology, the strata that contain the petroleum oils can be quite readily identified as of a particular era, geologically, by a number of methods, such as magnetic anomalies or radiometric evaluation, plus fossil info is found in  these areas, and give us a clock through which we can identify the age of the locale in question.

Just as a passing thought, these are the methods that tell us, that Great Britain started its life above the waves, as a part of the Southern polar regions, and drifted north, when the historic Gondwana land, separated, parting Africa from the Americas, they also tell us the future to a degree, and ours is that Europe will be under water, to a depth of the Eiffel tower within a thousand years, even without global warming and current sea rises, Scotland will survive as it is still growing but England is sinking anyway, in the southern areas, and much of the coast is to be abandoned by the present government, as it feels the coastal protection is just too expensive to maintain.

So, shortly, the north east and southern regions will start to slide into the sea, losing about five miles off our coastal measurements.....in  your lifetimes...alas most of France will survive, areas like the Massif Centrale, will become living spaces, not nature reserves, and the Alps and Switzerland, Germanies Zugspitz, etc, but their time will come too, makes me wonder, why anybody would want to emigrate here, and leave this as a legacy for their children to face..we should all be thinking about getting out, and where we should be going, to.....

Most of Americas eastern coast line will also suffer this as well, and they also face the collapse of the Cumbraevietta, ( an island volcano, across the Atlantic ocean ), some time in the relatively near future..when that baby goes, the US will face a tidal wave, one thousand feet high, hitting ALL the eastern seaboard, and running forty miles inland as well, ( when it hits New York it will almosty certainly trigger the "Ramapo" fault, that this city sits on, ( and three mile Island, the nuclear generation plant that was the cause of a major leak some years back, this baby has been geologically inactive for too long a period as well, from  historic data, it is overdue a seismic event, ), and geological history says that this is not the first time this has happened....at the moment this volcano is building up to a real tragedy, but it is not the worst future event they face, a super volcano is sitting below the Yellowstone national park, and is showing signs of sinking at one end ( 18 feet in 7 years), leaving many trees underwater, it has exploded at least six times in Americas history, from the geology, and looks set to do so again shortly, in geological terms, it is in fact a regular phenomenon , that is actually quite predictable, it is now nearly a hundred years behind schedule, so your guess, is as good as mine, but I will not be visiting, any time in the near future.

When this goes, it will open a hole in the earth about sixty kilometres across, and blot out the sky for a hundred years, the "nuclear winter" scenario ( i.e. dirt thrown up by atomic bombs circulating around the globe, at high altitudes, for years to come, plunging the world into a deep freeze ),  and lowering sunlight levels), will take place, crop failure will be common and the Thames will freeze over again, the few nations that survive will find life very hard for some time to come, and some may never recover, it will be a mass extinction event, for many species, mankind may just be amongst them.....do enjoy what is left of your weekend. Bye.....