One of the most widespread beliefs about fossil fuels — oil, natural gas and coal — is that these substances started out as dinosaurs. There’s even an oil company, Sinclair, that uses an Apatosaurus as its icon. That dino-source story is, however, a myth. What is true: These fuels got their start long, long ago — at a time when those “terrible lizards” still walked the Earth. Show Fossil fuels store energy in the bonds between the atoms that make up their molecules. Burning the fuels breaks apart those bonds. This releases the energy that originally came from the sun. Green plants had locked up that solar energy within their leaves using photosynthesis, millions of years ago. Animals ate some of those plants, moving that energy up the food web. Others plants just died and decayed. Any of these organisms, when they die, can be turned into fossil fuels, notes Azra Tutuncu. She’s a geoscientist and petroleum engineer at the Colorado School of Mines in Golden. But it takes the right conditions, including an oxygen-free (anoxic) environment. And time. A whole lot of time. The coal we burn today got its start some 300 million years ago. Back then, dinosaurs roamed the Earth. But they didn’t get incorporated into coal. Instead, plants in bogs and swamps died. As this greenery sunk to the bottom of those wet areas, it partially decayed and turned into peat. Those wetlands dried out. Other materials then settled down and covered the peat. With heat, pressure and time, that peat transformed into coal. To extract coal, people now have to dig deeply into the earth. Petroleum — oil and natural gas — comes from a process that started in ancient seas. Small organisms called plankton lived, died and sank to the bottom of those oceans. As debris settled down through the water, it covered the dead plankton. Microbes dined on some of the dead. Chemical reactions further transformed these buried materials. Eventually, two substances formed: waxy kerogen and a black tar called bitumen (one of the ingredients of petroleum). Explainer: All crude oil is not alikeThe kerogen can undergo further changes. As debris buries it deeper and deeper, the chemical becomes ever hotter and subjected to more pressure. If conditions become just right, the kerogen transforms into the hydrocarbons (molecules formed from hydrogen and carbon) that we know as crude oil. If temperatures become hotter still, kerogen becomes the even smaller hydrocarbons that we know as natural gas. The hydrocarbons in oil and gas are less dense than the rock and water in Earth’s crust. That prompts them to migrate upward, at least until they get trapped by some ground layer that they can’t move past. When that happens, they gradually build up. This forms a reservoir of them. And they will stay in it until people drill down to release them. How much is there?There is no way to know how much coal, oil and natural gas lie buried within the Earth. Even putting a number on that amount would not be very useful. Some of these fossil fuels simply will be in places from which people cannot safely or affordably extract them. And even that can change over time, Tutuncu notes. Some 20 years ago, she says, scientists knew where they could find what they call “unconventional resources.” These were accumulations of oil and gas that couldn’t be obtained through traditional drilling techniques. But then companies figured out new and less costly ways to bring up these resources. Scientists Say: FrackingOne of these methods is hydraulic fracturing. Better known as fracking, it’s when drillers inject a mix of water, sand and chemicals deep into the ground to force out the oil and gas. In the foreseeable future, Tutuncu says, “I don’t think we will run out [of fossil fuels]. It’s just a matter of improvements in the technology [to extract them affordably].” The burning of fossil fuels creates carbon dioxide and other greenhouse gases. These can contribute to climate change and global warming. For that reason, many scientists have warned that people should stop using fossil fuels. Alternatives, such as wind and solar power, don’t produce greenhouse gases. Giving up fossil fuels entirely, though, won’t be easy, at least in the near future, Tutuncu says. These substances are used for more than just producing energy. Plastics and many other products include fossil fuels in their recipes. Scientists and engineers will have to come up with environmentally friendly replacements for all those products if society chooses to wean itself off of its current reliance on fossil fuels. Much of the world's energy comes from material formed hundreds of millions of years ago, and there are environmental consequences for it. 1:01 What Are Fossil Fuels? Learn how human use of fossil fuels—non-renewable energy sources, such as coal, oil, and natural gas—affect climate change. ByChristina Nunez Published April 2, 2019 • 5 min read Decomposing plants and other organisms, buried beneath layers of sediment and rock, have taken millennia to become the carbon-rich deposits we now call fossil fuels. These non-renewable fuels, which include coal, oil, and natural gas, supply about 80 percent of the world’s energy. They provide electricity, heat, and transportation, while also feeding the processes that make a huge range of products, from steel to plastics. When fossil fuels are burned, they release carbon dioxide and other greenhouse gases, which in turn trap heat in our atmosphere, making them the primary contributors to global warming and climate change. Major types of fossil fuelsThere are several main groups of fossil fuels, including: Coal: Black or brown chunks of sedimentary rock that range from crumbly to relatively hard, coal began to form during the Carboniferous period about 300 to 360 million years ago, when algae and debris from vegetation in swamp forests settled deeper and deeper under layers of mud. Mined via surface or underground methods, coal supplies a third of all energy worldwide, with the top coal consumers and producers in 2018 being China, India, and the United States. Coal is classified into four categories—anthracite, bituminous, sub-bituminous, and lignite–depending on its carbon content. Please be respectful of copyright. Unauthorized use is prohibited. Please be respectful of copyright. Unauthorized use is prohibited. Please be respectful of copyright. Unauthorized use is prohibited. Please be respectful of copyright. Unauthorized use is prohibited. Please be respectful of copyright. Unauthorized use is prohibited. Please be respectful of copyright. Unauthorized use is prohibited. Please be respectful of copyright. Unauthorized use is prohibited. Please be respectful of copyright. Unauthorized use is prohibited. Please be respectful of copyright. Unauthorized use is prohibited. Please be respectful of copyright. Unauthorized use is prohibited. Please be respectful of copyright. Unauthorized use is prohibited. 1 / 11 1 / 11 <p>An iceberg melts in the waters off Antarctica. Climate change has accelerated the rate of ice loss across the continent.<br> </p> An iceberg melts in the waters off Antarctica. Climate change has accelerated the rate of ice loss across the continent. Carbon dioxide emissions from burning coal account for 44 percent of the world total, and it's the biggest single source of the global temperature increase above pre-industrial levels. The health and environmental consequences of coal use, along with competition from cheap natural gas, have contributed to its decline in the U.S. and elsewhere. But in other places, such as India, demand is expected to rise through 2023. Oil: Crude oil, a liquid composed mainly of carbon and hydrogen, is often black, but exists in a variety of colors and viscosities depending on its chemical composition. Much of it formed during the Mesozoic period, between 252 and 66 million years ago, as plankton, algae, and other matter sank to the bottom of ancient seas and was eventually buried. Extracted from onshore and offshore wells, crude oil is refined into a variety of petroleum products, including gasoline, diesel, and heating oil. The top oil-producing countries are the U.S., Saudi Arabia, and Russia, which together account for nearly 40 percent of the world's supply. Petroleum use accounts for nearly half the carbon emissions in the U.S. and about a third of the global total. In addition to the air pollution released when oil is burned, drilling and transport have led to several major accidents, such as the Exxon Valdez spill in 1989, the Deepwater Horizon disaster in 2010, the devastating Lac Megantic oil train derailment in 2013, and thousands of pipeline incidents. Nonetheless, oil demand continues to rise, driven not only by our thirst for mobility, but for the many products—including plastics—made using petrochemicals, which are generally derived from oil and gas. Natural gas: An odorless gas composed primarily of methane, natural gas often lies in deposits that, like those for coal and oil, formed millions of years ago from decaying plant matter and organisms. Both natural gas and oil production have surged in the U.S. over the past two decades because of advances in the drilling technique most people know as fracking. By combining fracking—or hydraulic fracturing—with horizontal drilling and other innovations, the fossil-fuel industry has managed to extract resources that were previously too costly to reach. As a result, natural gas has surpassed coal to become the top fuel for U.S. electricity production, and the U.S. leads the world in natural gas production, followed by Russia and Iran. Natural gas is cleaner than coal and oil in terms of emissions, but nonetheless accounts for a fifth of the world's total, not counting the so-called fugitive emissions that escape from the industry, which can be significant. Not all of the world’s natural gas sources are being actively mined. Undersea methane hydrates, for example, where gas is trapped in frozen water, are being eyed as a potential gas resource. Reducing emissions from fossil fuelsGovernments around the world are now engaged in efforts to ramp down greenhouse gas emissions from fossil fuels to prevent the worst effects of climate change. At the international level, countries have committed to emissions reduction targets as part of the 2015 Paris Agreement, while other entities—including cities, states, and businesses—have made their own commitments. These efforts generally focus on replacing fossil fuels with renewable energy sources, increasing energy efficiency, and electrifying sectors such as transportation and buildings. However, many sources of carbon emissions, such as existing power plants that run on natural gas and coal, are already locked in. Considering the world's continuing dependence on fossil fuels, many argue that in addition to efforts aimed at replacing them, we also need to suck carbon from the air with technologies such as carbon capture, in which emissions are diverted to underground storage or recycled before they reach the atmosphere. A handful of commercial-scale projects around the world already capture carbon dioxide from the smokestacks of fossil fuel-fired plants, and while its high costs have prevented wider adoption, advocates hope advances in the technology will eventually make it more affordable. What are the 3 sources of fossil fuels?Coal, crude oil, and natural gas are all considered fossil fuels because they were formed from the fossilized, buried remains of plants and animals that lived millions of years ago.
How is fossil fuel formed?FOSSIL FUELS FORM. After millions of years underground, the compounds that make up plankton and plants turn into fossil fuels. Plankton decomposes into natural gas and oil, while plants become coal. Today, humans extract these resources through coal mining and the drilling of oil and gas wells on land and offshore.
What are the 4 main fossil fuels?Petroleum, coal, natural gas and orimulsion are the four fossil fuel types. They have a variety of physical, chemical and other essential properties in general, but the most vital thing regarding fossil fuels, perhaps, is that they are not green. Fossil fuels are made from plants and animals that decompose.
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What are fossil fuels made out of
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