Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Natural Cataclysms Predict Glaciations

11.01.2002


Not only geologists are interested in giant canyons of Kursk Magnetic Anomaly, but also soil scientists. There is very convenient place to watch old soils, which earlier were on the surface. As the canyons grew wider, details of ancient landscapes and their changes appear. While studying one of those canyons, Svetlana Sycheva from the Institute of Geography Russian Academy of Sciences has found that earlier there was a system of large ravines, now buried under a thick layer of sediments.



It was found that the landscape and soil changes do not occur randomly, in fact, they are strictly periodic - the glacier epochs take turns with interglacial ones. The old gully, which Sycheva was studying, formed about 130 thousand years ago, at the end of the Dneprov icing, when there was a sudden, even catastrophic climate change. Dry and cold weather, which caused permafrost in Central Russia, was changed by wet and warm Mikulin interglacial period. When sudden soil defrost came and too much water flowed in because of glacier thawing, soils began to cover all the ravines, even large ones.

As the climate settled and warming came, the newly formed earth relief acquired vegetation and soils developed. The gully was `resting`, being covered with forests. That lasted for 15 thousand years. At the end of Mikulin interglacial period, a series of cataclysms happened, because of frequent changes of warmth and frost. After a long drought, severe fire broke out and destroyed forests in gullies. Without vegetation, the slopes destructed and fertile soils were washed out. By the middle of Valday icing (50-40 thousand years ago), the gully was covered with sediments from water flows.


Sycheva believes that the history of old gullies and ravines is the perfect model of changes between glacial and interglacial epochs. Most natural cataclysms - long droughts, floods, early frosts - happen in these transition periods. Forest fires in interglacial periods are not so destructive, they clean the landscape and promote flora renewal. On the contrary, the fires in the beginning of glacial periods are dangerous to soils - they freeze faster, erode, become salted. So the soils, which are fertile now, may become unusable because of rather natural reasons.

We are living just in this time - the end of the Holocene interglacial period, which started about 10 thousand years after Valday icing. The scientists explain the increase in the number of catastrophes as a result of natural factors. For the next 3-4 thousand years there may be severe climate changes - from hard droughts to sudden chills, with general tendency to cold.

Tatiana Pitchugina | alphagalileo

More articles from Earth Sciences:

nachricht Global study of world's beaches shows threat to protected areas
19.07.2018 | NASA/Goddard Space Flight Center

nachricht NSF-supported researchers to present new results on hurricanes and other extreme events
19.07.2018 | National Science Foundation

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>