Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Seismic rocker aims to cut the noise

21.02.2005


A Canadian seismologist is arguing that our understanding of the structure of the Earth’s interior is based on the equivalent of fuzzy ultrasound images that leave room for improvement.



Once seismic images are fine-tuned to remove background noise, they may tell a very different story of the world below, says Dr. Felix Herrmann, a seismologist at the University of British Columbia. And oil companies are already lining up to cash in on his clearer view of the Earth’s underbelly.

Dr. Herrmann says that there has been a push to gather more data from beneath the ground through initiatives such as US ARRAY, but that these data cannot be properly used without a better understanding of how seismic images are produced.


Until now, he says, scientists have interpreted transitions in the mantle in terms of changes in a complex cocktail of substances below the earth’s surface. However, he says, his research has led to a theory that, instead of this accepted complex mineralogical composition, the seismic data could be showing a complex interplay of only two different types of substances.

"Think of what happens when you mix a French and a Swiss cheese," says Dr. Herrmann. "You have Swiss cheese and you start to mix in more and more French cheese. At some point, you would call it a French cheese. When this happens, basically there is a critical point. That’s a point where all of a sudden the material starts to become like the French cheese – and a sharp transition occurs, whose fine structure we hope to observe from noisy seismic data."

He will present the results of his latest seismic imaging research at the 2005 American Association for the Advancement of Science meeting in Washington D.C. on February 19.

With seismic imaging, scientists bounce sound waves into the Earth, or record natural tremors, and use the reflected waves to construct an image of the Earth’s interior structure in much the same way that ultrasound technology enables us to peer into the womb and see a fetus.

But Dr. Herrmann says that previous seismic images of the Earth’s interior were distorted by noise. Noise is created by things like tremors, wind or even a truck driving on the surface, as well as by flaws in measuring devices and mathematical models.

As a result, while we were expecting to be painting in geological blue, we should really be thinking in an earthy pink. "What I’m proposing is certainly a different way of thinking," says Dr. Herrmann.

While the scientific world has yet to fully adopt Dr. Herrmann’s view, oil companies are eagerly taking a closer look at his "de-noising" and mixture-model techniques. His seismic imaging research has led to a recent partnership with four large oil companies to use these clearer imaging techniques to find the world’s most elusive oil patches.

"Oil prices are not high for nothing," notes Dr. Herrmann. "It’s more and more difficult to find petroleum resources. The big oil fields have been found, and now people want to find smaller fields. That means we need to look with a finer resolution, and also to look deeper."

We also need to better understand what we see in these images, he adds.

"That’s where both the ’cheese model’ and noise come in, because noise limits how fine a structure you can actually resolve to learn about these rapid changes in the Earth’s properties."

Dr. Herrmann’s new theory of the earth’s transitions, co-written with MIT’s Dr. Yves Bernabé, was published in the December 2004 issue of Geophysical Journal International.

Dr. Felix Herrmann | EurekAlert!
Further information:
http://www.eos.ubc.ca

More articles from Earth Sciences:

nachricht Water - as the underlying driver of the Earth’s carbon cycle
17.01.2017 | Max-Planck-Institut für Biogeochemie

nachricht Modeling magma to find copper
13.01.2017 | Université de Genève

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Water - as the underlying driver of the Earth’s carbon cycle

17.01.2017 | Earth Sciences

Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

17.01.2017 | Materials Sciences

Smart homes will “LISTEN” to your voice

17.01.2017 | Architecture and Construction

VideoLinks
B2B-VideoLinks
More VideoLinks >>>