Helium PBL

What is Helium, where is it made, and where can we find it?

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.

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?

Where is helium made?

• Helium is made by fusion (In Stars)

• Helium is made by fission (decay) Earth

What elements produce helium?• Helium is known to be produced by the decay of various

radioactive elements, principally;• Uranium• Thorium• Radium• With 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.

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.

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 fumaroles

• It 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 States

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 Mountains

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.

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)

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 block

Panhandle Hugoton field in Texas

Geologic cross section

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.

Here is the castlegate sandstone in Utah, does this cross-section look familiar?

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.

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.

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.

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