A new approach to gas exploration has discovered a huge helium gas field, which could address the increasingly critical shortage of this vital yet rare element.
Helium doesn't just make your voice squeaky - it is critical to many things we take for granted, including MRI scanners in medicine, welding, industrial leak detection and nuclear energy. However, known reserves are quickly running out. Until now helium has never been found intentionally - being accidentally discovered in small quantities during oil and gas drilling.
Now, a research group from Oxford and Durham universities, working with Helium One, a helium exploration company headquartered in Norway, has developed a brand new exploration approach. The first use of this method has resulted in the discovery of a world-class helium gas field in Tanzania.
Gould’s Belt, interstellar clouds, and the Eocene–Oligocene helium-3 enhancement
Author:
Rubincam
Abstract:
Drag from hydrogen in the interstellar cloud which formed Gould’s Belt may have sent interplanetary dust particle (IDPs) and small meteoroids with embedded helium to the Earth, perhaps explaining part the helium-3 flux increase seen in the sedimentary record near the Eocene–Oligocene transition. Assuming the Solar System passed through part of the cloud, IDPs in the inner Solar System may have been dragged to Earth, while dust and small meteoroids in the asteroid belt up to centimeter size may have been dragged to the resonances, where their orbital eccentricities were pumped up into Earth-crossing orbits; however, this hypotheses does not explain the Popigai and Chesapeake Bay impacts.
In recent years the subject of sending humans back to the Moon has largely gone mute, initially overwhelmed by talk of NASA’s Asteroid Redirect Mission, and more recently by the agency’s media drumbeat about sending humans to Mars. Because of this, there is also subsequently very little talk about a weird bit of magical thinking that often accompanies discussions of humans on the Moon: mining the Moon for helium-3 to power nonexistent fusion reactors. But that magical thinking still lurks, like a small burning ember in a burned-down house, waiting for a chance to flare up again. Last month at the Mars Society convention in Washington, DC, the subject of helium-3 briefly sparked once more, brought up by one of its longtime proponents, Apollo astronaut Harrison Schmitt.
Schmitt is probably the smartest astronaut who walked on the Moon, and certainly the most educated. He is a Harvard-trained geologist who NASA admitted to the Apollo program under pressure from Congress, and his presence undoubtedly increased the scientific return of his Apollo 17 mission as well as the entire program considering his role in training astronauts on earlier missions. Schmitt can still deliver graduate-level geology lectures if given the opportunity. But he also embraces the dubious scientific and engineering idea of mining helium-3 on the Moon for use in fusion reactors.
The last big flurry of articles and publications, and even a congressional hearing, about helium-3 fusion occurred in 2007, when NASA was still planning to send humans to the Moon. NASA did not drive that discussion then, but rather Schmitt and a few others. But even eight years later helium-3 still pollutes the environment of discussions about human spaceflight, despite its very nebulous assumptions.
Helium is the second most abundant element in the Universe, but it's relatively rare on Earth – so much so that some have called for a ban on party balloons to ward off a worldwide shortage. However, a team of scientists led by Diveena Danabalan of Durham University conducted a new study that indicates that there may be vast new sources of the gas in the western mountain regions of North America.
First detected in the spectrum of the Sun, in a century and a half helium has become a key resource in our high-tech world. The noble gas is used in cryogenics, MRI scanners, semiconductor manufacturing, welding, deep-sea diving, and blimps and balloons – though the latter makes up a surprisingly small fraction of the demand.
The problem is that even though helium makes up almost a quarter of all matter in the Universe, it's very rare on Earth with the main supply coming from natural gas wells in North America. This is because helium is a very light element that, once it escapes into the air, floats off into space. Hydrogen is lighter, but it's common on Earth because hydrogen is captured in molecules of water or organic compounds. Helium, on the other hand, forms no compounds even with itself except a few highly unstable ones under extraordinary laboratory conditions.
Recent studies have pointed to a drastic decline in known helium reserves and no large discoveries to replace them. This being the case, the fear is that we may run out of helium so soon that some scientists, such as Cambridge University chemist Peter Wothers, are calling for an end to its use in party balloons.
For the new study, a team of scientists from Durham and Oxford Universities looked at natural gas regions in North America, where they subjected gas samples from 22 wells in the United States and Canada to mass spectroscopy. By analyzing the isotopes of helium, neon, and argon, they were able to gain a better understanding of how helium is produced, transported, and trapped in the Earth.
Most helium on Earth is helium-4 (4He), which is produced by radioactive decay deep inside the planet. Over hundreds of millions of years, it migrates up to the crust, where it is released during periods of tectonic activity. By comparing the ratios of 4He with neon-20 (20Ne) in the helium-rich Hugoton-Panhandle gas field running through Texas, Oklahoma, and Kansas, the team found that released helium dissolves in groundwater, which transports it to natural gas deposits. According to Danabalan, This mechanism indicates that much more helium is waiting to be tapped than previously thought.
"We identified neon isotope tracers which show a strong association between helium and groundwater," says Danabalan. "This means that in certain geological regions, groundwater transports large volumes of helium into natural gas fields, where trapping potential is greatest. This suggests that we have probably underestimated the volumes of helium which are actually available to explore.
