Cross-section showing the tectonic activity that shapes the Lost City.
3. The Lost City Is A Collection Of Hydrothermal Vents
You’ve probably heard of Old Faithful, famous geysers at Yellowstone National Park. It is a hydrothermal vent, meaning that it is a fissure in the surface of the earth from which water and other subterranean compounds erupt. The Lost City is an underwater system of hydrothermal vents.
The Lost City is located at the base of Atlantis Massif, a large mountain in the Mid-Atlantic Range that is about the size of Mount Ranier in Washington. The hydrothermal vents present the most extreme underwater environment that we currently know of; they test the limits of where life can exist.
4. The Vents Produce Molecules Necessary For Generating Life
Life is possible when certain molecules become arranged in such a way that they are able to replicate on their own. The most important of these molecules are DNA, the macromolecule that houses every single gene that an organism has.
The extreme conditions at the Lost City generate the molecules necessary to create amino acids, which are the building blocks of DNA. Studying the conditions there can help scientists to understand better how life originated and whether or not the process can be replicated in other extreme conditions, such as on other planets.
Image of new mineral growth forming on one of the chimneys.
5. Scientists Study The Field To Understand The Origin Of Life
The molecules that are produced by the vents in the Lost City are produced in an extreme environment that is unlike any other on earth. Some scientists hypothesize that the particular molecules produced by these vents, combined with the intensely hot, alkaline environment can lead to abiotic genesis.
Abiotic genesis refers to the generation of life from non-living (non-biological) material. If abiotic genesis is something that actually can and does occur, scientists believe that they will find it at the Lost City. What’s more, if abiotic genesis can occur at the Lost City, astrobiologists believe that those conditions may be similar to the creation of life on other planets.
The DSV Alvin and ROV Argoll are both submersibles that are owned by the United States Navy. A submersible is an underwater vessel that is designed to travel to extreme depths and withstand intense pressure. They have long been exploring the Mid-Atlantic Ridge, and Alvin was involved in the exploration of the Titanic wreck when it was discovered in 1986.
On December 4, 2000, crews were using the submersibles to explore the Mid-Atlantic Ridge when they came across the chimneys of the Lost City. They transmitted photographs of the chimneys to the scientists behind the exploration, and the scientists realized that what they had just found was truly incredible.
7. The National Science Foundation Soon Began Funding Explorations Of The Lost City
In 2003, three years after the initial discovery of the Lost City, the National Science Foundation took an interest in exploring them further. Scientists from the NSF used the submersible Alvin to make a 32-day voyage specifically for creating a bathymetric map of the hydrothermal vents.
A bathymetric map is similar to a topographic map; they both show differences in elevation across a specified area. The creation of the bathymetric map of the Lost City helped to pave the way for future explorations because the scientists would know the depths that they needed to plan for.
The Lost City is a place that is teeming with vibrant life. The difference between the life found at the vents and life located in many other parts of the ocean is the size. While many creatures found throughout the ocean are large enough to be seen with the naked eye (and many are quite large indeed!), those found at the Lost City are generally less than one centimeter in length.
The hydrothermal vents are replete with bacteria and other forms of microbial life. The fact that life can thrive in this intense environment makes the Lost City a ripe area for research on micro-organisms.
9. The Lost City Pushes The Extremes Of Where Life Can Exist
Parts of the Lost City, especially in more interior areas, are anoxic, meaning that there is no oxygen present. Additionally, the pH is a staggering 9-11, making it so highly alkaline that most life forms would be unable to live there. Throw in the high heat – the temperature ranges from 120 degrees Fahrenheit to nearly boiling – and you may wonder what life could exist there at all.
That life can exist in such an extreme environment is indeed a puzzle for scientists and one that they are happy to seek out the answer to by studying the Lost City.
10. The Vents Have Been Active For Over 120,000 Years
In fact, data shows that some of the vents may have been active for over 150,000 years. 150,000 years ago, human civilization was far from even beginning. This makes the structures found at the vents much, much older than anything built by humans.
This means that they are the oldest continually-active hydrothermal vents on the ocean floor. The chimneys – the stacks that have built up around the vents – are so large because the vents have been emitting minerals and other materials from beneath the ocean floor for so many thousands of years.
11. The Field Has Thirty Vents, Both Active And Inactive
Because of the composition of the mineral-enriched water that spews out of the vents, the chimneys that have formed around the vents are composed mostly of calcite, brucite, and aragonite. As a result, the chimneys have a white color.
Some of the vents are active, meaning that they routinely spew heated water from beneath the ocean floor. Some are inactive, meaning that they emitted the heated water in the past but currently do not. However, they may begin doing so again in the future.
12. The Vents Release The Gases Hydrogen And Methane
The hydrogen concentration at the Lost City is considerably higher than even the highest hydrogen concentrations in similar environments that do not experience the eruptions that the vents at the Lost City do. Hydrogen is the most abundant element in the universe.
The vents also release considerable amounts of methane, a hydrocarbon gas that is formed when one carbon atom combines with four hydrogen atoms. Methane is a very powerful greenhouse gas, and it contributes to the high temperature of the water found at the vents.
13. The pH Of The Surrounding Water Is Affected By The Vents
A neutral pH – room-temperature water that has not been ionized – is 7. Anything below 7 is considered to be acidic. Lemon juice and vinegar, both acidic, have a pH of 2. Battery acid, the most corrosive acid there is, has a pH of 0.
Anything above 7 is considered to be alkaline, or basic. Regular sea water has a pH of 8, and bleach has a pH of 12. The water surrounding the vents has a pH of between 10 and 11, depending on the location, making it markedly more alkaline than regular sea water.
14. They Do Not Produce Significant Quantities Of Metals
Most water, especially mineral-rich water – such as that emitted by underground sources – tends to have at least trace amounts of metals, such as iron, nickel, and copper. However, the heated water that the vents emit is remarkably low in metals, perhaps most notably magnesium.
Because of the low metal content, hydrocarbons – such as methane – are able to form. If abiotic genesis is possible, scientists believe that the source may be hydrocarbons. Another result of the low metal content of the emitted water is that serpentinization reactions occur, which give the vents their characteristic chimneys.
15. The Lack Of Metals Creates Unique Chemical Reactions
Perhaps the most notable chemical reaction that occurs at the Lost City is known as “serpentinization.” Despite the sound of the name, serpentinization has nothing to do with Harry Potter. Rather, it refers to the production of rocks that have a green, scaly surface, similar to the skin of a serpent.
The serpentinization that occurs at the vents is known as ultramafic-hosted serpentinization. This process leads to the creation of hydrocarbons and other molecules that some scientists believe are the source of abiotic genesis.
16. The Largest Vent Chimney Is Known As “Poseidon”
Poseidon is nearly 200 feet tall, making it the most prominent and easily-recognizable feature of Lost City. Poseidon is actually crowned by four smaller chimneys that have formed by the tens of thousands of years of heated, mineral-rich water being emitted by its source vent.
Surrounding Poseidon is buttresses of smaller chimneys and other deposits that have built up around it. It basically looks like a giant cave formation – like stalactites and stalagmites that were formed by centuries or even millennia of dripping water.
17. The Temperatures Of The Emissions Are Up To 91 Celsius
The temperatures at the vents are incredibly high. The coolest temperatures are around 40 degrees Celsius, which is well over 100 degrees Fahrenheit. The boiling point is 100 degrees Celsius, so for the temperatures at the vents to hit 91 degrees means that the water coming out is basically steam.
That life can thrive in this intensely hot environment is nothing short of remarkable. Keep in mind, though, that large life forms – such as crabs, eels, and fish – while present, are not abundant. Most life at the vents is microscopic, less than 1 centimeter across.
18. One Result Of The Chemical Reaction Is The Synthesis Of Hydrocarbons
Hydrocarbons are molecules composed only of carbon and hydrogen molecules. One hydrocarbon that is particularly dominant at the Lost City is methane, which consists of one carbon molecule joined to four hydrogen molecules. Hydrocarbons are important because they are part of the process of serpentinization, which gives the Lost City its characteristic white chimneys.
You are probably more familiar with hydrocarbons than you think. Petroleum and other fossil fuels are composed of hydrocarbons. Additionally, some chains of hydrocarbons are known as fats. The classification of “saturated” or “unsaturated” refers to the number of single- or double-hydrogen bonds in the hydrocarbons.
19. Some Scientists See Hydrocarbons As Evidence For Abiogenesis
Scientists believe that abiotic generation, also known as abiogenesis, of hydrocarbons may occur at the vents of the Lost City. Some evidence suggests that hydrocarbons with low molecular weight may be synthesized at the vents, through a unique type of reaction that occurs at the basement rocks.
Scientists believe that the abiogenesis of hydrocarbons could be evidence of the abiotic generation of life, meaning life emerging from non-living matter. Hydrocarbons are an essential component of DNA, the building block of life. DNA is a molecule that is able to replicate itself, so it is possibly the smallest, most basic form of life.
Some scientists think that the abiotic genesis of low-weight hydrocarbons is not necessarily evidenced for the abiotic genesis of life. There is a large leap from the generation of low-weight hydrocarbons, such as methane, and the generation of DNA molecules.
Microscopic forms of life do exist at the vents, and some of the lifeforms there do not exist anywhere else that we know of. However, there may be other ways to explain their presence, such as the genetic mutation that enable them to thrive in the extreme environment of the vents.
21. Abiogenesis Is An Aspect Of Darwinian Evolution
Abiogenesis is the process of life deriving from non-life material. Charles Darwin was concerned primarily about where species come from and devised his theory of evolution to show that there are species that derive from common ancestors. They differentiate to adapt to their environments through the idea of “survival of the fittest,” thereby developing into the different species that we see today.
Other scientists have since taken his theory to show that life is derived from non-living matter, such as molecules that organize themselves into amino acids and DNA. To better understand this process of abiogenesis, many scientists have been studying the Lost City.