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

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>