Portable CT Scanner Examines Earth Core Samples

Roland Piquepaille writes "Scientists from the Lawrence Berkeley National Laboratory (Berkeley Lab) have built the worldâ(TM)s first x-ray computed tomography (CT) scanner able to look at core samples directly from remote drilling sites, thus eliminating the previous needs to send the samples to laboratories. Barry Freifeld, a mechanical engineer in Berkeley Lab's Earth Sciences Division, and his team, built a refrigerator-sized, 300-kilogram scanner and they installed it on the JOIDES Resolution Drill Ship operated by the Ocean Drilling Program. The scanner has so far traveled to the Oregon coasts and Prudhoe Bay in Alaska, analyzing more than 2,000 feet of core samples. Now, it's scheduled for another trip from Bermuda to Newfoundland. You'll find more details in this summary."

World Tour!

[Transcendent]

The scanner has so far traveled to the Oregon coasts and Prudhoe Bay in Alaska, analyzing more than 2,000 feet of core samples. Now, it's scheduled for another trip from Bermuda to Newfoundland.

T-Shirts are now available for the scanner's World Tour with a complete listing of cities on the back including Minsk, Dunedin, and Kangerlussuaq! Supplies are limited, so don't miss this once-in-a-lifetime opprotunity and order your's now!

Re:World Tour!

[terpia]

As far as I know, Oregon only has one coast.. Perhaps thy're counting the Columbia river which is basically the Northern border of the state.

Re:World Tour!

[bhtooefr]

Just steal my sig...

Lens?

[4of12]

I was intrigued by the aluminum half cylinder they used to attenuate the X-rays going through the core sample.

Is this some crude kind of X-ray lens?

Re:Lens?

[Viadd]

Is this some crude kind of X-ray lens?

No, it's just to reduce the flux from the beams of X-rays that just graze the periphery of the core sample. That way the detector doesn't have to be robust enough to accurately measure the full unattenuated X-ray beam while also being sensitive enough to measure the few photons that pass through the full diameter of the core.

Everything is straight-line optics without any refraction or reflection.

Re:Lens?

[dunedan]

I don't know if this is what they are doing with this detector but you can use mirros to "focus" x-rays at very shallow angles.

This is how sattelite xray observatories work

More information is available with pictures at Chandra X-ray Observatory [harvard.edu]

Re:Lens?

[Imabug]

A similar kind of filter is also used in CT scanners used on patients. It's called a butterfly filter, because of it's shape and does the same purpose: Attenuate the portion of the beam passing through the periphery of the body more than the portion of the beam passing through the center. That way the x-ray flux at the detector is more or less normalized, and you don't get huge variations in x-ray intensity across the length of the detector.

In the early days of CT, when it was first developed and only h

Re:Lens?

[SEWilco]

Imagine taking a large garbage bag filled with water, and resting it on your head so it surrounds the top of your head.

Imagine holding your breath while the bag full of water is on your face.

Look at my egg

[Caractacus Potts]

Awesome! I have a dinosaur egg that I'd like CT'ed, just in case there's something interesting inside of it. My dentist's X-ray machine isn't powerful enough to resolve any details. Thinks they'd stop by my house for a visit?

Not a big breakthrough

[Anonymous Coward]

I work for a facility that builds custom x-ray CT scanners for toxic waste barrels and stored munitions. The technology is almost the same, and we've implemented it dozens of times. I guess they're just now scanning dirt. *yawn*

Re:Not a big breakthrough

[GeoGreg]

Perhaps this is the first shipborne CT scanner? I wouldn't know if being on a ship would be any different that, say, being mounted in a trailer.

Earth Core Scanner

[SEWilco]

I preferred the Earth Core Scanner which found the formation at the center of the Earth's core. But as it consists of all the seismographs on the Earth's surface, it is only as portable as the Earth is.