Drilling for facts: Leicester geologist aboard Pacific research boat
Just over a year ago, Japan suffered its worst disaster for decades when an undersea earthquake triggered a massive tsunami. Now one of our geologists is aboard a research ship studying the nature of that quake.
JFAST is the Japan Trench Fast Drilling Project, a collaboration between the Japan Agency for Marine Earth Science and Technology (JAMSTEC) and the International Ocean Drilling Project (IODP). Dr Louise Anderson is aboard the Drilling Vessel Chikyu, maintaining a stable presence above the quake epicentre, and recently found the time to post a guest blog about the project for Scientific American (co-written with Dr Christie Rowe from McGill University).
It is fortunate that the D/V Chikyu with its specialist equipment wasn’t destroyed, like so many other Japanese vessels, when the tsunami hit Hachinohe port (especially as some schoolchildren were being given a tour of the ship at the time). Quick thinking by the captain and crew got everyone off safely and the only significant damage was to one of six thrusters which the vessel uses, along with sophisticated GPS, to maintain its exact position in mid-ocean. Fortunately, the system has redundancy built in and so the ship is able to operate with only five functioning thrusters.
In the SciAm blog, Louise and Christie explain the unusual nature of the March 2011 quake which created such an extreme effect:
Ironically, this unusual quake also offers an invaluable opportunity to study aspects near the surface which would normally be buried far underground. The international team - which includes scientists from Germany, Italy, France, Canada, India, New Zealand and China as well as the UK, USA and Japan - are using systems called Logging-While-Drilling (LWD) and Measurement-While-Drilling (MWD).
These techniques involve instruments located immediately behind the drill bit, enabling the researchers to study the nature of the borehole and the surrounding rock as it is being drilled, rather than lowering instruments into a pre-drilled hole. LWD and MWD data will provide a continuous record of rock properties across this important fault zone.