Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists obtain rocks moving into seismogenic zone

13.10.2009
IODP Expedition 322 of the Nankai Trough Seismogenic Zone Experiment Stage 2 complete

An international group of scientists aboard the Deep-Sea Drilling Vessel CHIKYU, operated by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) for the Integrated Ocean Drilling Program (IODP), return from a 40-day scientific expedition off the shore of the Kii Peninsula, Japan on Oct. 10, 2009.

Expedition 322, called "Subduction Inputs" in the multi-stage project, conducted drilling, logging and sampling beneath the ocean floor to investigate input material that will be transported to the seismogenic zone by the plate subduction system.

The drilling operations were carried out at two sites in the Shikoku Basin, the back-arc basin of the Izu-Bonin volcanic chain where the Philippine Sea Plate dives down into the Nankai Trough at a rate of about 4 cm per year. At the first site C0011, scientists began coring from a depth of 340 meters below the seafloor. The coring, however, had to be abandoned at a depth of 881 meters because of damage of the drill bit. At the second site C0012, coring was carried out from depths 60 meters to 576 meters below the seafloor, and successfully collected the targeted sedimentary and basement rock samples.

Dr. Michael Underwood, professor at University of Missouri, USA, and co-Chief Scientists of the expedition said, "We identified an interface of Miocene sediment and basement rock around 540 meters beneath the seafloor and successfully sampled basaltic pillow lava rocks that make up the basement." He added "These sedimentary and volcanic rocks in the lower part of Shikoku Basin are key intervals for generating large earthquake slip after they are transported to the seismogenic zone. Studying their petrological, geotechnical, frictional and hydrogeological properties prior to subduction is expected to contribute significantly to the understanding of rupture dynamics in the seismogenic zone."

The science party included 26 onboard research specialists from international member countries. "Scientists observed, measured and analyzed geological samples by day and night working shifts in the onboard laboratories," said Dr. Saneatsu Saito from JAMSTEC who led research activities as another co-Chief Scientist. He explained the importance of the variety of data obtained, "The sand-rich volcanic sediments were confirmed in large quantity and may have been transported from the easterly located Izu-Bonin Arc about 5 to 11 million years ago. Other sandstones contain abundant minerals derived from land, implying the extensive supply of sand to the Shikoku Basin from the Japanese islands." Prof. Underwood added, "Analysis of pore water and hydrocarbon gases retrieved from the sedimentary layers above the basement indicates multiple sources and migration paths of fluids. These results have important implications for understanding the properties of fluids within the seismogenic zone."

The IODP Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) is an ocean drilling project that drills in the plate boundary fault and the megasplay fault believed to have generated tsunami. It aims to gain insight into the transition from aseismic to seismic slip within the plate boundary fault zone, as well as the processes of earthquake or tsunami occurrences, by collecting geological samples and measuring geophysical conditions. The research project consists of four stages in all, planned to conduct drilling operations at several sites located along a line orthogonally crossing the Nankai Trough region from Shikoku Basin (seaward) to Kumano Basin (landward). The first stage was carried out between September 21st, 2007 and February 5th, 2008. To learn more about NanTroSEIZE, visit www.iodp.org/NanTroSEIZE/

IODP is an international marine research drilling program dedicated to advancing scientific understanding of Earth by monitoring, sampling, and instrumenting subseafloor environments. Through multiple platforms, preeminent scientists explore IODP principal themes: the deep biosphere, environmental change, and solid Earth cycles. IODP has operated since October 2003, funded jointly by the Japan Ministry of Education, Culture, Sports, Science and Technology and the U.S. National Science Foundation. Additional support is provided by the 17-member European Consortium of Ocean Research Drilling, the People's Republic of China, the Republic of Korea, Australia, India, and New Zealand. www.iodp.org

IODP-MI | EurekAlert!
Further information:
http://www.iodp.org

More articles from Earth Sciences:

nachricht Arctic melt ponds form when meltwater clogs ice pores
24.01.2017 | University of Utah

nachricht New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland
19.01.2017 | University of Gothenburg

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Scientists spin artificial silk from whey protein

X-ray study throws light on key process for production

A Swedish-German team of researchers has cleared up a key process for the artificial production of silk. With the help of the intense X-rays from DESY's...

Im Focus: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | 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

 
Latest News

Breaking the optical bandwidth record of stable pulsed lasers

24.01.2017 | Physics and Astronomy

Choreographing the microRNA-target dance

24.01.2017 | Life Sciences

Spanish scientists create a 3-D bioprinter to print human skin

24.01.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>