Geoscientists Drill Deepest Hole in Ocean Crust in Scientific Ocean Drilling History

Jan 25, 2010
Seawater sprays on the rig floor of the research vessel JOIDES Resolution during drilling operations. Credit: William Crawford, IODP/TAMU

(PhysOrg.com) -- For eight weeks beginning in November 2009, off the coast of New Zealand, an international team of 34 scientists and 92 support staff and crew on board the scientific drilling vessel JOIDES Resolution (JR) were at work investigating sea-level change in a region called the Canterbury Basin. It proved to be a record-breaking trip for the research team.

For eight weeks beginning in November 2009, off the coast of New Zealand, an international team of 34 scientists and 92 support staff and crew on board the scientific JOIDES Resolution (JR) were at work investigating sea-level change in a region called the Canterbury Basin. It proved to be a record-breaking trip for the research team.

The JR is one of the primary research vessels of an international research program called the Integrated Ocean Drilling Program (IODP). This research took place during IODP Expedition 317.

IODP is supported by two lead agencies, the U.S. National Science Foundation (NSF) and Japan's Ministry of Education, Culture, Sports, Science, and Technology.

At present 10 percent of the world's population lives within 10 meters of sea level. Current predict a 50-centimeter to more than one-meter rise in sea level over the next 100 years, posing a threat to inhabitants of low-lying coastal communities around the world.

To better understand what drives changes in sea level and how humans are affecting this change, scientists are "looking to our past for answers and digging back as far as 35 million years into the Earth's history to understand these dynamic processes," says Rodey Batiza of the NSF's division of .

From November 4, 2009 to January 4, 2010, the IODP research team drilled four sites in the seafloor. One site marked the deepest hole drilled by the JR on the (1,030 meters), and another was the deepest hole drilled on a single expedition in the history of scientific ocean drilling (1,927 meters).

Another record was broken for the deepest sample taken by scientific ocean drilling for microbiological studies (1,925 meters).

A fourth record was achieved when the team recovered sediment from the shallowest water site (85 meters) ever drilled for science by the JR.

Scientists with the Integrated Ocean Drilling Program set new drilling records off New Zealand. Credit: IODP

"This was one of only two JR expeditions that have attempted to drill on a continental shelf--this was not a routine operation for this ship," says co-chief scientist Craig Fulthorpe of the University of Texas at Austin, who led the expedition with co-chief scientist Koichi Hoyanagi of Shinshu University in Japan.

The unstable, sandy composition of the sediments and the relatively shallow water of the shelf environment present unique challenges for a floating drilling platform like the JR, which relies on thrusters to maintain position and requires special technology to accommodate wave motion.

"We never expected we would be able to drill this deep in such a difficult environment," says Fulthorpe.

Canterbury Basin is part of a worldwide array of IODP drilling investigations designed to examine global sea level changes during Earth's "Icehouse" period, when sea level was largely controlled by changes in glaciation at the poles.

Before Canterbury, IODP sea level change studies included sites near the New Jersey coast, the Bahamas, Tahiti, and on the Marion Plateau off northeastern Australia.

Canterbury Basin was selected as a premier site for further sea level history investigations because it expanded the geographic coverage needed to study a global process. It displays similar sequence patterns to New Jersey studies.

Data from both the Canterbury Basin and the New Jersey shelf IODP expeditions will be integrated to provide a better understanding of global trends in sea level over time.

Global sea level has changed in the Earth's past; these changes are influenced by the melting of polar ice caps, which increases the volume of water in the ocean.

Locally, relative sea level can also change as a result of tectonic activity, which causes vertical movement in the Earth's crust.

Together, glaciation and tectonic forces create a complex system that can be difficult to simulate with climate models. This necessitates field studies like the Canterbury Basin expedition, say geologists, to directly analyze samples.

The Canterbury Basin expedition set out to recover seafloor sediments that would capture a detailed record of changes in sea level that occurred during the last 10 to 12 million years, a time when global sea level change was largely controlled by glacial/interglacial ice volume changes.

The research team also recovered samples documenting changes in ocean circulation that began when movements in Earth's tectonic plates separated Antarctica from Australia, creating a new seaway between the two continents about 34 million years ago.

Canterbury Basin is one of the best sites in the world for this type of survey because it is located in a tectonically-active region and therefore has a relatively high rate of sedimentary deposition, which, like the pages of a book, record detailed events in Earth's climate history.

Beyond breaking records, the IODP Canterbury Basin expedition achieved its goal of recovering a 10-million-year record of sea level fluctuations, with one drill hole extending back 35 million years.

Cores revealed cyclic changes in sediment type and physical properties (such as magnetic susceptibility) that are believed to reflect switches between glacial and interglacial time periods.

Even longer cycles were originally identified using seismic images generated using sound waves.

Understanding the relationship between these seismic "sequences" and global change is an important objective for post-expedition research, say expedition geologists.

Explore further: New satellite maps out Napa Valley earthquake

Related Stories

Scientists look at global sea level rise

Oct 12, 2005

Scientists from nine nations are involved in the Integrated Ocean Drilling Program's Tahiti Sea Level Expedition, investigating global sea level increases.

Gas hydrates research expedition begins

Sep 23, 2005

An international team of scientists has started a six-week expedition off the coast of Vancouver Island to conduct research beneath the Earth's crust.

New Antarctic Drilling Record to Yield Major Climate Data

Dec 22, 2006

The Antarctic Geological Drilling (ANDRILL) Program drilled to a new record depth of 1,000 meters below the seafloor from the site on the Ross Ice Shelf near Scott Base in Antarctica on Dec. 16, making ANDRILL the most successful ...

Recommended for you

Tropical Storm Dolly forms, threatens Mexico

11 hours ago

Tropical Storm Dolly formed off Mexico's northeastern coast on Tuesday and headed toward landfall in Tamaulipas state, threatening to spark floods and mudslides, forecasters said.

Giant garbage patches help redefine ocean boundaries

13 hours ago

The Great Pacific Garbage Patch is an area of environmental concern between Hawaii and California where the ocean surface is marred by scattered pieces of plastic, which outweigh plankton in that part of ...

New satellite maps out Napa Valley earthquake

14 hours ago

Scientists have used a new Earth-observation satellite called Sentinel-1A to map the ground movements caused by the earthquake that shook up California's wine-producing Napa Valley on 24 August 2014.

User comments : 11

Adjust slider to filter visible comments by rank

Display comments: newest first

Shootist
3.1 / 5 (9) Jan 25, 2010
"At present 10 percent of the world's population lives within 10 meters of sea level. Current climate models predict a 50-centimeter to more than one-meter rise in sea level over the next 100 years, posing a threat to inhabitants of low-lying coastal communities around the world."

What threat? Have they not feet? Can they not walk? My 95 year old grandmother can walk fast enough to escape this putative flooding.

A little less hyperbole would probably engender less caustic comments.
codesuidae
4.7 / 5 (3) Jan 25, 2010
"A fourth record was achieved when the team recovered sediment from the shallowest water site (85 meters) ever drilled for science by the JR."

Well, that one shouldn't be too hard to beat. Anyone going to the beach this weekend and want to take a stab at it?
SincerelyTwo
5 / 5 (3) Jan 25, 2010
Shootist,

I was just at the beach and walked away from the incoming tantrum of surging sea level rise. The trick to it is to face away from the water and take a single step forward, that should be good for a year... but be well prepared for the year after, it might require a bit larger of a step.

Moving the infrastructure of any coastal cities is another matter however...
Shootist
1.8 / 5 (5) Jan 25, 2010
Guess it's like being the faster runner . . . with one leg.

The Kola Institute, of the former USSR, reached a depth of 12,260m, though not on a single drilling attempt.
Cyberadvan321
1 / 5 (4) Jan 25, 2010
Frankly, all this offshore drilling is pretty reckless, in my opinion. Especially the offshore oil drilling platforms. A recent offshore blow-out near Australia created an oil slick hundreds of square miles long, and took weeks to plug. If a blow-out occurs on a large enough under-sea oil cavern, and cannot be plugged, it could spew out an oil slick large to cover the entire surface of the worlds oceans, suffocating all marine life underneath the slick, depriving it of oxygen. This could quickly result in the suffocation of every form of life on the planet, including ours.
Parsec
4 / 5 (4) Jan 26, 2010
"At present 10 percent of the world's population lives within 10 meters of sea level. Current climate models predict a 50-centimeter to more than one-meter rise in sea level over the next 100 years, posing a threat to inhabitants of low-lying coastal communities around the world."

What threat? Have they not feet? Can they not walk? My 95 year old grandmother can walk fast enough to escape this putative flooding.

A little less hyperbole would probably engender less caustic comments.


A little more thought would probably engender less critical comments as well. Your 95 year old grandmother can probably walk a lot faster than her house. Wiping out 10% of the housing stock of the world would cost a lot of trillions of dollars in monetary losses. In addition, sea level changes combined with flood surges will cause a lot of flooding with no time to run anywhere, much less walk. For heaven's sake, use your brain guy!
DachpyarviIe
2 / 5 (8) Jan 26, 2010
So they will only take the results from two drillings to prove global warming is happening. This is not enough data and a control should have been done, preferably in the Andes, to show what a scam global warming is. The emails prove it, I have them all, still reading, and if they don't prove that all science is bunk then nothing will :)
Shootist
1.8 / 5 (5) Jan 26, 2010
Your 95 year old grandmother can probably walk a lot faster than her house. Wiping out 10% of the housing stock of the world would cost a lot of trillions of dollars in monetary losses. In addition, sea level changes combined with flood surges will cause a lot of flooding with no time to run anywhere, much less walk. For heaven's sake, use your brain guy!


And nothing you said threatens my grandma, my parents, my children or me.

Yeah if 10% of the housing was wiped out in one fell swoop, you'd be right. Otherwise, if you don't like the weather, move.

barakn
4 / 5 (4) Jan 26, 2010
@Dachpyarvile-
A control? There's no telling why you think a control is needed for a core drilling, but the Andes would be a particularly awful control. What makes you think that a core drilled in a terrestrial erosional environment down into a jumbled mix of sedimentary, metamorphic, and igneous rock of various ages is going to be an adequate control for a core into an orderly pile of marine sediments on the opposite side of the globe? I'd also like to know why you're making the false claim that they're only using "two drillings" when this expedition alone drilled in 4 location, this ship has drilled on at least one other expedition, and plenty of other cores have been obtained by other teams? Methinks you aim to confuse, not to inform.
codesuidae
not rated yet Jan 26, 2010
"if they don't prove that all science is bunk then nothing will :)"

There is something vaguely circular in searching for evidence that all science is bunk. I like it. Are you a Discordian?
Skeptic_Heretic
1 / 5 (3) Jan 28, 2010
barakn, you've been fooled by the pseudo-commentor.

Interesting article, let's see what the core reveals when they analyse the samples.