Design of a Deep-Sea Bacterial Mat Sampler

Woods Hole Oceanographic Institution

Woods Hole Oceanographic Institution Team: Leena Peters, Modupe Adegoke, Emma Dalton, Mara Pagano

2009-2010: In collaboration with Woods Hole Oceanographic Institution (WHOI), this student team designed and built a sampling system to interface with the Jason II remotely operated deep-sea vehicle to collect bacterial mat from the sea floor.  The study of such bacterial mats is of great interest to a variety of scientists, but the layered and highly sensitive structure of the mats makes their retrieval a difficult task.

The team initially generated a number of different design concepts for the sampler, ranging from layer-based suction approaches to whole-sample cores with closure mechanisms.  The team then selected the “coring with closure” paradigm for its ability to maintain the layer structure of the bacterial mat, and further developed two specific concepts that leverage an inflating bladder to seal the bottom of the coring tube.  The team designed and built functional prototypes of each of the two designs, evaluating their effectiveness with simulated bacterial mat in the laboratory.  The team also designed and built an interface system to connect the sampler with the submersible’s robotic arm.

Ultimately, the instrument will become part of the basic suite of sampling devices available to users of the National Deep Submergence Facility vehicles, following testing in situ and modification based on performance at sea.