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Towed camera systems are commonly used to collect photo and video images of the deep seafloor for a wide variety of purposes, from pure exploratory research to the development of management plans. Ongoing technological developments are increasing the quantity and quality of data collected from the deep seafloor. Despite these improvements, the area of seafloor, which towed systems can survey, optically remains limited by the rapid attenuation of visible wavelengths within water. We present an overview of a new towed camera platform integrating additional acoustical devices: the ocean floor observation and bathymetry system (OFOBS). The towed system maintains continuous direct communication via fiber optic cable with a support vessel, operational at depths up to 6000 m. In addition to collecting seafloor photo and video data, OFOBS gathers sidescan data over a 100-m swath width. OFOBS functionality is further augmented by a forward looking sonar, used to aid in hazard avoidance and real-time course correction. Data collected during the first field deployments of OFOBS, at a range of seamounts on the Langseth Ridge/Gakkel Ridge intersection (86 degrees N, 61 degrees E) in the high Arctic in September 2016, are presented to demonstrate the functionality of the system. Collected from a location with near continuous ice cover, this explanatory data set highlights the advantages of the system for deep-sea survey work in environments currently difficult to access for the majority of subsurface research platforms.

An Integrated Sediment Disturber (ISD) was developed to study the effects of repeated physical disturbances on sediment geochemistry and associated benthic fauna. The ISD is capable to generate a strong, more or less uniform mixing of surface sediments by three rotating fork-like disturber units of approximately 1 m in diameter. Perturbations can be set at different intensities and frequencies, e.g., on times scales of hours, days, or weeks, depending on the experimental design. The ISD carries an Autonomous Positioning Drive (APD) module, which allows the three-dimensional positioning of sensors by a programmable controller. The three circular disturbed zones and an undisturbed control area in-between can be monitored at specified frequencies using a microprofiler with microelectrodes for measuring various parameters (e.g., oxygen, pH, hydrogen sulphide). All operations are supervised by a digital stills camera. Sediment sampling at the start and end point using coring devices handled by divers (and potentially undertaken using a Remotely Operated Vehicle) provides material to study shifts in biodiversity of the small sedimentinhabiting biota and alterations in ecosystem functioning in response to perturbations and the changing geochemical characteristics of surface sediments.