History of use

How long does it take to petrify?

Every fossil is a small miracle. As Bill Bryson points out in his book A Short History of Almost Everything, only one bone in a billion becomes a fossil. By this calculation, the entire fossilized legacy of the 320 million people living in the United States today, for example, would consist of about 60 bones—or less than one-fourth of the human skeleton. Less than 1/10 of one percent of all species that have ever existed have become fossils. But if you try, you can greatly increase your chances of eternal life, at least in this form. Ever wanted to become a fossil? If we imagine that these 60 bones will be scattered over an area of ​​9,88 million kilometers, the chances of finding these bones in the future are almost non-existent. In general, fossilization (or fossilization) is such an unlikely process that scientists estimate that less than 1/10 of one percent of all species that have ever existed have become fossilized. And certainly not all were discovered. Humans have a certain advantage in this regard: we have heavy skeletons and are relatively large. Thus, we are more likely to undergo fossilization than a jellyfish or a worm. However, there are some things that will help you stay in the ground for a long time. Taphonomy is the science of burial, decay, and preservation—that is, the processes that occur after an organism dies and becomes fossilized. To find out how to become a fossil, the BBC spoke to the world’s best taphonomists.

Dig in and hurry up

“Maintaining good body condition after death is a big issue. Long enough to sink into sediment and then change physically and chemically deep underground to become a fossil,” says Sue Beardmore, a taphonomist at Oxford University’s Natural History Museum. “To survive for millions of years, you must also survive the first hours, days, seasons, decades, centuries and thousands of years,” adds Susan Kidwell, a professor at the University of Chicago. “That is, you need to survive the initial transition from the ‘taphonomically active zone’ to the permanent burial zone, where your remains are unlikely to be exhumed.”

There are infinitely many ways to disrupt successful fossilization. A lot can happen at a depth of 20-50 centimeters, in the soil or on the seabed. The remains may be eaten and scattered by scavengers, for example, or exposed to the elements for too long. You also don’t want them to be disturbed or moved by digging animals. You should dig as deep as possible When it comes to rapid burial, natural disasters can come to the rescue – floods, for example, which submerge huge volumes of sedimentary rocks or volcanic eruptions. “One theory is that dinosaur bones were deposited initially in dry conditions that led to the death of the dinosaurs, and then currents carried away the sediment that buried them,” Beardmore says. Of course, we are used to burying human bodies at a depth of two meters (without cremation). But this is not enough.

Find water

Of course, the first step is to die, but you can’t die anywhere. We need to find a suitable place. It is also worth remembering about water. If you die in a dry environment, as soon as the scavengers find you, your bones will definitely end up on the surface. Most experts agree that it is better to dive into sand, mud and sedimentary layers, and lakes, floodplains and rivers, or the bottom of the sea are best suited for this. “The paleoenvironments where we find the best fossils are lakes and river systems,” says Caitlin Sime, a taphonist at the University of Queensland in Brisbane, Australia. An important factor is the speed with which fresh sediment buries the object. She recommends rivers that flow from mountains, which cause erosion and carry a lot of rainfall. Another option is a coastal delta or floodplain, where river sediments are quickly dumped as water flows out to sea. The ideal would be an “anoxic” environment, in which there is very little oxygen and in which animals and microorganisms cannot exist that could disturb and digest the remains. Kidwell recommends avoiding diving 50 centimeters below the seabed because crabs, shrimp, worms and other creatures tend to burrow at that depth.

“You need to get to a place as quickly as possible with a relatively low rise so that it sinks into sediment rather than rises, and preferably with standing water – a pond, lake, estuary or ocean – so that it becomes anoxic.”

In rare cases, fossils created in these types of calm, anoxic conditions retain their soft tissues—skin, feathers, and innards. Feathered dinosaurs were found in China, and the first birds, Archeopteryx, were found in Bavarian quarries. Most experts agree that it is better to dive into sand, mud and sedimentary layers, and for this, lakes, floodplains and rivers, or the bottom of the sea are best suited Once your fossils are below the biologically active surface layer, they will steadily sink deeper and deeper as sediment accumulates, Kidwell says. The risk of destruction in this case moves to a completely different geological scale, namely tectonics. The question is how long it will take for the sediments surrounding the corpse to turn into solid stone, only to be raised by geological activity to a height where erosion can expose the remains.

Refuse the coffin

Now we move on to the technical aspects of fossilization—and what kind of fossil your body can become. In very general terms, anything 50 years old can be called a “subfossil.” They are mostly composed of original body tissues. Extinct Pleistocene megafauna found in caves, such as giant ground sloths in South America, cave bears in Europe, and marsupial lions in Australia, would be good examples. However, if you want your remains to become a fossil that will last millions of years, you will need minerals that can seep through your bones and replace them with harder substances. This process, known as “permineralization,” is what creates a complete fossil. And it can last for millions of years. In short, you won’t need a coffin at all. Bones are replaced with minerals most quickly when mineral-rich water flows through them, feeding them iron and calcium. The coffin, of course, will keep the skeleton in beautiful shape, but will interfere with this process. However, there is a method that can work in a coffin. Mark Archer, a palaeontologist at the University of New South Wales, suggests burial in a concrete coffin filled with sand, with hundreds of 5mm holes drilled into the sides. It then needs to be buried deep enough to allow groundwater to pass through.

“If you want to become a classic bony fossil like a Canadian dinosaur, coarse river sand will do the job. All soft tissue will be destroyed, and you will be left with a perfectly defined skeleton.”

For minerals, calcium ions are great because they can precipitate out as calcite, a form of calcium carbonate. “They will begin to cement or cover the body and protect it in the long term because it will likely lie at great depth.” Deliberately seeding your body with suitable minerals such as calcite or gypsum will also speed up the process. Encouraging the growth of hard iron-rich minerals is also wise because they resist weathering in the long term. Paleontology is quite an interesting science Silicates from sand are also suitable for inclusion. Archer even noted that you could cover the body with copper strips and nickel pellets if you like nice fossilized blue bones and teeth.

Avoid the edges of tectonic plates

If you survive the first few hundred thousand years and minerals begin to replace your bones, well, congratulations! You have successfully become a fossil. As sediment layers accumulate above you and you sink deeper into the Earth’s crust, heat and pressure will take their toll (and your body). But that is not all. Your fossil may be buried so deep that it is melted by the heat and pressure of the Earth. How to avoid this? You need to stay away from the edges of tectonic plates, where the crust will eventually be swallowed up by the surface. One of the subduction zones is in Iran, where the Eurasian plate overhangs the Iranian plate.

Let them find you

Let’s think about the discovery potential of your fossils. If you want to give someone a chance of one day finding your carefully preserved body, you need to plan a burial in a place that is currently low enough to accumulate the sediment needed for deep burial—but also to allow it to rise back up again. In other words, you will need a place where weathering and erosion will eventually expose the surface layers containing your remains. For example, the Mediterranean Sea. It gets smaller as Africa moves towards Europe. Other small inland seas are also suitable. For example, the Dead Sea. High salt content will preserve your body and marinate it properly

You can stay in amber

We have looked at the standard method of creating hard, durable, bony fossils largely replaced by stone. But there are other unusual methods. For example, amber. There are many fossils perfectly preserved in this gem made from tree resin – birds, lizards and even the tail of a feathered dinosaur found in Myanmar. “If you can find a large amount of tree resin and wrap it in amber, you guarantee excellent preservation of your soft tissue and bones,” says Sime. “But it won’t be easy for an animal as big as you.” Amber can preserve remains for a long time Can’t find enough amber? The next option would be the tar pits that preserve saber-toothed cats and mammoths at La Brea in Los Angeles. Although in this case you will lose your shape, your bones will be mixed up with other animals. You can also freeze in a rock or in a glacier, like Otzi the Bigfoot, found in the European Alps in 1991. The next option would be natural mummification, where your body simply dries out in a cave system. “There are many cave systems with remains coated with groundwater calcium that also form stalactites and stalagmites,” says Sime. “People like caves, and if they still exist in the future, you can use them.” Finally, there is another way to preserve your corpse almost forever, albeit not in fossil form: launch it into space. Or leave it on the surface of a geologically inert celestial body without an atmosphere, such as the Moon.

“The vacuum of space can perfectly preserve the body,” says Sime. And he adds that they will have to attach a radio beacon to it in order for it to ever be found.

Caves are always a good option

What will be left for later?

Let’s say you lay there safe and sound for millions of years. What else can stay with you? Plastics (yes, fidget spinners), other petroleum-based products that don’t biodegrade, and inert materials (alloys, gold and rare metals, which are abundant in cell phones) can also survive. Glass is also quite resistant and can withstand changes in temperature and pressure. Perhaps in the future they will find smartphones. Where would you like to be found? Tell us about it on our Telegram channel. Those who are interested in paleontology probably know what fossilization and fossils themselves, fossils or fossils, are. Fossilization is a set of physical and chemical processes that turn living organisms into fossils. It’s no secret that fossilization takes thousands, or even tens of thousands of years. But let’s look at this topic in more detail. We learn about the processes taking place, what conditions are needed and what unique fossils we can find.

What is fossilization?

Fossilization is a long-term process of replacing the tissues of living organisms with minerals. After burying the remains of an animal or plant, the voids in them are filled with groundwater, followed by mineralization. In this way, small organisms are very well preserved, which are quickly covered with various sediments – silt or sand. Thanks to mineralization, the detailed structure of, for example, tiny pterosaurs reaches us, down to the details of the organization of the wing membrane. Large organisms cannot quickly become covered with the necessary layer and have time to be severely destroyed before petrifying. Therefore, we know the feather structure of small birds, but we know little about large sauropods. The preservation of fossils also depends on the time when the organism existed. The older the rocks, the more erosion (destruction) they were subjected to. Cambrian deposits (540-485 million years ago) are several times smaller than Neogene deposits (23-2,5 million years ago), and as a result, we have several times fewer preserved organisms of the Cambrian period.

Conditions required for fossilization

Conditions may be completely different, but it is important to isolate the body from environmental influences and various microorganisms. Ideal conditions for the preservation of organisms can include hot and dry deserts and icy wastelands, as well as wet swamps or rivers with a thick layer of silt. Paleontologists have found complete skeletons of large animals that date back millions of years in both permafrost and sandstone strata. One of the most impressive finds was the brain of an iguanodon, more than 130 million years old, with well-preserved vessels and tissues. A lucky coincidence buried the brain in the acidic environment of the swamps before the tissue began to decompose and be devoured by bacteria. The mammoth babies Lyuba and Chroma were no less grandiose find. Today they have been well researched, right down to the restoration of some sections of their DNA. But the most amazing discoveries awaited us in 2017. Sometimes it happens that bacteria that consume the remains of a dead animal, on the contrary, help us preserve it. After the death of, for example, a fish, a whole layer of various organisms forms on the decomposing flesh, rushing to a feast. After which, they, along with the fish, are covered with sediment. The black silhouettes of animals on the stone that we find are nothing more than imprints of bacteria.

Amber

Jurassic Park showed us the most reliable source of preservation of ancient organisms – amber. Beautiful insects that are tens of millions of years old no longer surprise anyone. Unfortunately, no matter how much blood they drink, DNA does not persist for more than six million years, and we will not be able to create our own park with dinosaurs. But the finds of 2017 are amazing. A complete Cretaceous chick and feathered dinosaur tail, dating from the same period. Thanks to amber, the finds have reached us completely intact, and we can see the smallest details of the structure of feathers 100 million years old.

Organics and their traces

This is surprising, but after tens of millions of years, not only stones, but also some organic substances or their traces reach us. Thus, at the beginning of the 68s, Mary Schweitzer published the results of a study of the remains of a tyrannosaurus rex more than XNUMX million years old. They stated that not only the soft tissue structures of the dinosaur have reached us, but also the collagen protein contained in the bones and cartilage. But just a couple of decades ago we couldn’t even dream of something like this. No less surprising were the discoveries of melanosomes (an organelle that stores melanin and other pigments) of dinosaurs. Thus, we know the approximate color of some Mesozoic animals.

Group burials

Despite the fact that giant animals are poorly preserved, sometimes entire groups of large animals reach us in good condition. How does this happen? Perhaps the animals took the wrong path and got trapped in the tar lake. Or predators drove their victims into a swamp, where everyone drowned. Perhaps some catastrophe occurred that struck the entire family while incubating eggs. The area now known as the Hell Creek Formation was rich in clay-bottomed rivers, streams and swamps 66 million years ago, which contributed to such rich and high-quality burials. For example, during high tide or rain, the water level in some reservoirs rose greatly, but as soon as the water receded, some puddles became isolated from rivers and lakes. Fish and turtles died there, to the delight of paleontologists.

Сonclusion

Fossilization, or petrification, is a long-term physical and chemical process of transforming the remains of dead organisms and traces of their vital activity into a complex mineral structure with imprints of various tissues, and sometimes with organic molecules. The more favorable the conditions of the period were for fossilization, and the closer to us on the time scale, the more interesting details we can tell about this time.

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