May 20 (BBC) - A new deep-ocean record has been set for a scientific drilling operation.
Researchers working off the coast of Japan lowered a giant piston corer through more than 8km of water in order to pull sediments from the seabed.
It took two hours and 40 minutes simply for the equipment to descend into position above the ocean floor.
The drilling exercise, mounted from the Research Vessel Kaimei, is part of a project to read the history of great earthquakes in the region.
The chosen core site in the Japan Trench is very close to the epicentre of the Magnitude 9.1, Tohoku-oki event in 2011, which also produced a tsunami that devastated communities on the nation's eastern seaboard, and knocked out the Fukushima nuclear plant.
The 37m of sediment retrieved by the piston corer will hopefully preserve details of much older quakes - those that occurred before any written accounts.
The record coring occurred on the morning of Friday, 14 May, at a water depth of 8,023m (26,322ft).
