| Alaska, 1979 | |
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"We are sending down a lot of corers but we don't always get good cores. Lately the bottom has been hard or gravelly or both. Earlier it was soft, and we got one core that was almost 3 meters long. We take the cores and (1) split them, (2) test mechanical strength, (3) take samples from one half for microfossils, clay mineral, particle size distribution, bulk density, and something called an Atterberg sample, (4) photograph the other half, and (5) store both halves, the archive half and the work half, in the cooler. In addition, some cores to be studied in the lab are waxed to retain all the moisture."
The scientific crew retrieves a piston core. Even in smooth seas, we are secured to the deck and the corer is lashed all around for safety. The corer is a low-tech, gravity-powered instrument consisting of a large iron weight and a detachable steel barrel. A plastic sleeve inside the barrel holds the core and a stainless-steel fitting, the core catcher, keeps the core inside. The corer is lowered into the sea, then dropped from a short distance above the seafloor to fall freely. We lost more than one barrel during this cruise, but the ship's machinist fashioned replacement barrels and core catchers. The corer is painted on its side, "Penetration Or Bust."
