Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Breakthroughs in Geological Dating Imminent

22.08.2007
A breakthrough in geological dating can be expected within the next few years, combining existing methods to yield higher accuracy over longer time scales closer to the earth's origin.

This will bring great benefits not just for earth sciences, but also for other fields that rely on accurate dating over geological time. The developments ushering in a new generation of dating methods were discussed at a recent workshop on geochronological timing organised by the European Science Foundation (ESF).

The earth sciences rely on highly accurate timing to unravel past causes and effects, and understand the forces driving many events from ice ages to mass extinctions. Other scientific disciplines, such as evolutionary biology and climate science, in turn depend on accurate timing of geological processes to provide a baseline for their investigations. While significant progress has been made over recent decades, great uncertainties remain that are inhibiting investigations of major past events and formative processes in the earth sciences. In the case of the dinosaur extinction, knowledge of how long the process took would help resolve whether this was caused by a sudden asteroid strike or more gradually following a period of intense volcanic activity for example.

There was intense interest therefore in the ESF workshop, which came six years after the launch of an international project in the same field, called EARTHTIME. The workshop was organised to recognise and boost Europe's leading position in geochronology. It identified the need to improve the three main dating methods currently used, and cross-calibrate between them where possible to yield even greater accuracy, according to Klaudia Kuiper, scientific convenor of the ESF workshop. "The main outcome is that we first aim to work on the improvement of the numerical tools to calibrate the Geological Time Scale," said Kuiper.

Although these methods currently achieve high-sounding accuracies in the order of 0.5 percent to 1 percent, this can equate to an error of several million years over geological time scales. The objective is to reduce the error to better than 0.1 percent, in other words below an error of 100,000 years over a 100 million year time scale.

The three main tools currently used for dating geological events are argon-argon dating, uranium/lead dating, and astronomical methods. Argon-argon dating measures the level of decay from an isotope of potassium to argon, which occurs predictably over time, also taking account of the proportions of the two different isotopes of argon that form during the process.

Uranium/lead dating, one of the oldest and most refined methods, also exploits radioactive decay. However in this case the measurement is based on a correlation between the decay of two isotopes of uranium occurring at different rates, boosting the accuracy as result.

Astronomical timing is quite different, exploiting long term cyclical changes in the earth's orbit and axis. These cause climate changes that can be measured in sediment deposits, providing a dating method that can be correlated with geological events.

The methods each have pros and cons. Astronomical dating is highly accurate, but only over relatively short times on a geological scale, up to at most 250 million years, which is just 5 percent of the earth's age. Radiometric dating can span the earth's whole history back to 4.5 billion years ago, but with less accuracy, and some uncertainties. Currently the astronomical timing is used for events in the last 23 million years, then argon-argon back to 100 million years, and uranium/lead for older events.

Further progress can be made by combining these methods, with astronomical dating already being used to calibrate radiometric timing over the last 10 million years where the former is highly accurate. According to Kuipers, such progress will usher in a new generation of Geological Time Scale (GTS) measurements that will in turn yield fresh insights into critical events during the earth's history. Kuipers believed these could be just as exciting as some of the insights enabled by the previous generation of dating technologies, such as timing of the great ice ages of the Pleistocene between about 2 million and 11,000 years ago. The hope is that the new generation of timing methods will enable older events to be dated accurately.

The workshop Earthtime: The European Contribution - Integration of High-Precision Geochronology and Astronomical Tuning for Calibration of the Cenozoic and Mesozoic Timescales, was held 22-24 April 2007 in Amsterdam, Netherlands, and was convened by Klaudia Kuiper.

Each year, ESF supports approximately 50 Exploratory Workshops across all scientific domains. These small, interactive group sessions are aimed at opening up new directions in research to explore new fields with a potential impact on developments in science.

Thomas Lau | alfa
Further information:
http://www.esf.org
http://www.esf.org/activities/exploratory-workshops.html

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 >>>