Petersen grab

Petersen grab

[′pēd·ər·sən ‚grab]
(engineering)
A bottom sampler consisting of two hinged semicylindrical buckets held apart by a cocking device which is released when the grab hits the ocean floor.
References in periodicals archive ?
fluminea and samples of sediment were collected using a modified Petersen grab. All samples were dried in an oven (60[degrees]C) for 72 hours, macerated to obtain homogenous fine powders and sent for carbon ([[delta].sup.13]C) and nitrogen (81SN) isotopic value analysis in a mass spectrometer.
Ten samples of specimens of filter-feeding bivalve Corbicula fluminea (Muller, 1774) were taken in each period from the sediment below the cages using a modified Petersen grab (0.018 [m.sup.2] area); samples were collected below the culture cages.