What is Helium The atomic number of helium is 2 meaning each atom of helium has two protons Helium has the lowest melting point and boiling point of the elements so it only exists as a gas except under extreme conditions ID: 644754
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Slide1
Helium PBL
What is Helium, where is it made, and where can we find it?Slide2
What is Helium?
The atomic number of helium is 2, meaning each atom of helium has two protons.
Helium has the lowest melting point and boiling point of the elements, so it only exists as a gas except under extreme conditions.
Helium is the second-lightest element.Slide3
More on helium
Helium is
also the
second-most abundant element in the universe, though it is much less common on Earth.Helium is colorless, odorless, tasteless, non-toxic, and inert.Helium is the second-least reactive noble gas (after neon).
Thinking of these facts, why is it so difficult to store helium when it is found?Slide4
Where is helium made?
Helium is made by fusion (In Stars)
Helium is made by fission (decay) EarthSlide5
What elements produce helium?
Helium is known to be produced by the decay of various radioactive elements, principally;
Uranium
ThoriumRadiumWith Uranium being the highest production rate of 2.75X10
-5 [g/(year)(mm3)]Argon and Radon are by-products of the radioactive disintegration of potassium and radium, respectively, and are believed to have an origin similar to that of helium. Slide6
Facts about Argon and Radon
Helium has economic significance, is inert and safer then hydrogen.
Argon and Radon do not have economic significance
However Radon is considered an environmental hazard, because inhalation can cause cancer.Radon hazards are higher in areas of basement, and granites in particular.Slide7
Where is helium found on Earth?
Most helium is obtained by extracting it from natural gas
Helium is a common minor accessory in many natural gases
Helium occurs in the atmosphere at 5 ppm and has also been recorded in mines, hot springs and fumarolesIt has been found in oil field gases in amounts up to 8%
In North America helium-enriched natural gases occur in the Four corners area and Texas panhandle of the United StatesSlide8
More areas of helium production
In Canada the major concentrations along areas of crustal tension, such as the Peace River and Sweetwater arches
It is also found in the foothills of the Rocky MountainsSlide9
How much and where
Between 282 to 1.06 billion cubic feet of helium is generated from the decay of various radioactive elements
Based on this data the helium found in natural gas is widely believed to have emanated from deep-seated basement rocks, especially granite
Although the actual rate of production is slow and steady, the expulsion of gas into the overlying sediments cover may occur rapidly when the basement is subjected to thermal activity or fracturing by crustal arching.Slide10
Continued
The correlation between basement rocks and helium production is difficult to establish because helium tends to occur in deep, rather than shallow wells, and there is seldom sufficient well control to map the geology of the basement.
Helium also occurs from the breakdown of uranium ore bodies within sedimentary sequences (
Castlegate
, Central Utah) Slide11
The Texas Fields
The major source of helium in the United States is the Panhandle Hugoton field in Texas
This field locally contains up to 1.86% helium
This field is significant because it produces helium from sediments pinching out over a major granitic fault blockSlide12
Panhandle Hugoton field in TexasSlide13
Geologic cross sectionSlide14
Walther’s Law
A law stating that
lithologies
that conformably overlie one another must have accumulated in adjacent depositional environments.Another way of thinking of this is the ability to predict what the rock units will look like if the depositional environment changes.Slide15Slide16
Here is the
castlegate
sandstone in Utah, does this cross-section look familiar?Slide17
How could yourself or your team use Walther’s Law to find deposits or storage sites?
Take 3 minutes to brainstorm with you team members and come up with at least two ways in which this law will help your team solve the problem.Slide18
If Yellowstone Could Talk, It Might Squeak. Blame The
Helium
A huge amount of ancient helium is rising up from the rocks beneath Yellowstone National Park — about enough to fill up a Goodyear blimp every week.
The gas comes from a vast store of helium that's accumulated in the Earth's crust for hundreds of millions of years, scientists report in the journal Nature this week.
The helium is being released because in the past couple of million years — very recently, in geologic time — that old part of the crust has been feeling the heat from a huge volcano that is now sleeping underneath the park.Slide19
If Yellowstone Could Talk, It Might Squeak. Blame The Helium
Usually, volcanoes form at the edges of the tectonic plates that make up the Earth's crust.
"
It's a part of the crust that formed a very long time ago, billions of years ago, and it's basically been stable since that time,“. A
plume of molten rock from deep within the Earth has been pushing up into these old rocks.“ They've had this boring, peaceful existence and now suddenly they're put on the front
burner, They're
really getting cooked
. "All
that cooking is driving out helium that's been trapped inside the rock for a long
time. The
finding came as a surprise to scientists who look for clues about what's happening beneath Yellowstone by collecting the gases that bubble up.Slide20
If Yellowstone Could Talk, It Might Squeak. Blame The Helium
We
had sort of an 'Aha' moment where we realized, wow, that there's a lot of crustal helium coming out of Yellowstone — far more than we would have predicted,"
referring to a type of helium produced by the radioactive decay of elements in the Earth's crust
. As the researchers report in Nature, the amount being released by the rocks below Yellowstone is prodigious
. "
It's kind of an interesting thought to us, how these rocks behave," Evans says, "because it's very rare on the face of the Earth to have
vulcanism
come into rocks that have been that stable for that long
.“
Even
if Yellowstone weren't a protected national park, it wouldn't be economically practical to try to collect the gas — so don't expect to someday be blowing up party balloons with helium from Yellowstone