Modified Gravity Corer: Advantages and Offshore Testing

A modified gravity corer (MGC) for more efficient and high-quality sediment core sampling is considered. Such design elements as the core catcher, section muff joints, the weight, and loop have been modified; the crown and locking plate have been removed. As a result of comparative testing in the South Chukchi Basin of the Chukchi Sea, it is shown that the MGC sampled 30% longer cores than the standard gravity corer (SGC). Judging from the distribution of such a redox-sensitive element as iron in the cores, when the MGC is used, a surface oxidized film remains in sediments. Thus, the disturbance of properties and textures/structures of sediments under sampling is the lowest.