April 6, 2011

Researchers To Drill Chicxulub Crater

The Chicxulub crater in Mexico, the site of the asteroid strike that brought the dinosaurs to extinction 65 million years ago, is among the highlights of ocean drilling projects proposed for the next decade, reports BBC News.

The Integrated Ocean Drilling Program (IODP) plans to study the crater by drilling about a mile into the sea bed. IODP is also planning expeditions to study earthquakes, ancient climates and a long-term aim to penetrate the Earth's mantle for the first time.

IODP scientists outlined their plans at the European Geosciences Union (EGU) annual conference in Vienna. But, they also noted that funding is needed to secure the next generation of expeditions.

Kiyoshi Suyehiro, president and CEO of the IODP international consortium, said he hoped more earthquake-oriented research could take place around Japan's coasts.

"We are in the process of talking to funding agencies about the direction that should be taken," Suyehiro said.

The Japanese research vessel "Chikyu has so far been involved in trying to understand seismogenesis in southwestern Japan, which will also experience Magnitude 8-class earthquakes in years to come," he told members of the annual meeting.

"So we are forming an IODP science team to plan quickly for drilling in the region that produced the recent quake," he added.

The Chikyu is rigged with "riser" equipment designed to allow penetration more than 3.5 miles into the sea bed. The long-term goal is to place instruments in boreholes in the Nankai Trough, a region off Japan's coast capable of producing earthquakes and strong tsunamis, enabling real-time monitoring in three dimensions of the subduction zone where one of the Earth's great tectonic plates is sliding beneath another.

Suyehiro also noted an urgent need for better data on climate changes of the past in order to improve forecasts of future climate patterns.

"Ocean acidification, climate change, the effects on ecosystems and society - this is another area that requires deep understanding, and we cannot waste time in finding out how they are affecting our lives," he said.

Projects under IODP also have access to the US vessel Joides Resolution. The European Consortium for Ocean Research Drilling (ECORD) commissions "mission-specific platforms" as required.

Catherine Mevel of ECORD's Paris management agency said there are two planned projects of specific interest to Europe.

"One is the Arctic - we need to understand the tectonic evolution of the Arctic basin because it has a strong influence on global climate change," she told BBC News.

"There are gas hydrates trapped in margins that might be released into the atmosphere if the climate warms too much," she said.

Mevel also highlighted plans to drill in the Mediterranean. She noted the area was a hotbed of European climatic history over the past few million years -- and the area is a potential source of raw materials like lithium.

"Also, the Mediterranean is the most tectonically active part of Europe and has a long history of devastating geohazards - landslides, earthquakes, tsunami - and we want to instrument boreholes for long-term monitoring, because it's really key to understanding these active processes," Mevel said.

Among the projects outlined, the Chicxulub crater project is one that could be up and running by 2013. While boreholes have been drilled into the portion of the crater that is on dry land, Joanna Morgan, of the Imperial College in London, told EGU meeting delegates that the seafloor area had yet to be touched.

"Chicxulub is the only impact crater on Earth with a peak ring," Morgan said.

Peak rings are features observed in large craters on the Moon and on other planets. Smaller craters are just bowls with nothing in the middle. Larger ones tend to have a peak in the middle -- and even larger ones, have a central peak that becomes a ring.

"Something very strange has happened to these rocks during the impact event - this will tell us where they're from and what sort of shock pressure they were subjected to during the impact," said Morgan.

The cores will be studied for evidence of life-forms that might have arisen in the unusually hot and stressed environment.

Scientific oil drilling has a storied past, dating back to 1966 with the US Deep Sea Drilling Project. Current programs are operated on an international level in order to promote scientific excellence and to help eliminate costs. Even so, it can be very expensive. The Chikyu vessel can cost up to $200,000 per day to operate.

Due to the recent global economic downturn, governments will have to decide where they will prioritize their funding for such programs. However, understanding global impacts from such devastations as the recent Japan earthquake and tsunami is one important reason for investing in scientific drilling that can return big benefits to the world.


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