There is no debate over the fact that hydrogen remains the most abundant element all across the solar system. Being a source of clean energy, hydrogen is very well-suited in terms of sustainable development, and Earth, undoubtedly, is a natural hydrogen factory. But there is one more side to this story, as most hydrogen vents that have been reported to date happen to be pretty small, and the geological processes that are responsible for hydrogen formation and the quantities that can be preserved within the geological settings still remain unclear.
In order to better understand the availability when it comes to geological hydrogen, Institute of Oceanology of the Chinese Academy of Sciences (IOCAS) researchers as well as their collaborators discovered and evaluated a massive pipe swarm, which is a cluster of cylindrical geological structures that happens to have the remnants of hydrogen hydrothermal activity that’s located in the west of the Mussau Trench on the east Caroline Plate.
It is well to be noted that the Mussau Trench happens to be a fossil trench, which means that it is quite ancient, having started around 25 million years ago, and is at present an inactive trench that went on to cease the tectonic activity. The newly discovered pipe swarm called the Kunlun goes on to consist of pipes having diameters that range between 450 and 1,800 meters.
The study has been published in Science Advances.
Apparently, hydrothermal fluids, which are a mixture of heated water and dissolved minerals, go on to spray out by way of small tubes that range in diameter from centimeters to sub-centimeters, along sides of pockmarks, which are small, crater-like depressions in the large pipes, or through gaps or cracks within the breccia piles that are the accumulations of angular rock fragments. It is worth noting that most of the breccias that are found within the hydrothermal cracks happen to be partially yellowish because of microbial mats, which are the layers of microorganisms.
Just like the other hydrothermal fields, hydrothermal biotas, which are basically the communities of living organisms, are also found within the Kunlun pipe swarm. The scorpionfish, which is the apex predator of the ecosystem, is mostly found within the Kunlun pipe swarm.
As the apex predator biomass has to be far less as compared to its prey, researchers go on to anticipate a large chunk of microbial mat, which could be found within piles of breccia that are at the bottom of the pipe swarm.
Moreover, over 800 short-duration seismic events much like the small earthquakes have already been detected over a period of 28 days all through the 150-kilometer profile throughout the trench, hence putting the spotlight on the ongoing widespread active gas leakage all across the entire Mussau Trench.
Clumped nitrogen isotope analysis, which is a method for tracing gas origins when it comes to hydrothermal fluid samples, has gone ahead and revealed quite a dominant atmospheric gas component.
Previously reported hydrogen hydrothermal activity has been located nearby the active plate margins, for instance, the spreading ridges, or nearby the active transform faults, which go on to expose the mantle peridotite, like the Lost City.
In contrast to this, Kunlun hydrothermal fields, which are pretty large and also hydrogen-rich, are located almost 80 kilometers from active plate margins.
The fact is that these hydrothermal pipes happen to have steep walls as well as abundant breccias along with numerous generations of smaller bowl-shaped pockmarks at the bottom, which are similar to that of kimberlite, hence indicating many generations of explosions. Using empirically derived blast energy estimates, the formation of these large pipes would require millions of tons of TNT.
It is well to be noted that the most likely source of energy when it comes to the formation of such large pipes is hydrogen. Compressed hydrogen can actually release humongous amounts of energy. For instance, for one ton of hydrogen that expands adiabatically from 1,500 bar to 400 bar, the pressure, which is at the water depths of the Kunlun pipe swarm, can actually release the similar sort of energy as 0.21 tons of TNT.
In order to form such kinds of pipes, a massive amount of hydrogen would be required. Alternatively, a mixture of hydrogen as well as oxygen would indeed be highly explosive. Interestingly, one ton of hydrogen that reacts with oxygen happens to release 143 GJ of heat, which is, by the way, 150 times more energy as compared to the amount released through physical expansion.
As per Prof. Xiao Yuanyuan, who is the first author of the study, the inferences go on to suggest that potentially a massive amount of hydrogen may as well have been formed deep within the ocean lithospheric mantle. According to him, it could indeed be economically mineable in the times to come.
