a b s t r a c tTo enable detailed investigations of early stage hydrothermal plume formation and abiotic and biotic plume processes we developed a new oceanographic tool. The Suspended Particulate Rosette sampling system has been designed to collect geochemical and microbial samples from the rising portion of deep-sea hydrothermal plumes. It can be deployed on a remotely operated vehicle for sampling rising plumes, on a wire-deployed water rosette for spatially discrete sampling of non-buoyant hydrothermal plumes, or on a fixed mooring in a hydrothermal vent field for time series sampling. It has performed successfully during both its first mooring deployment at the East Pacific Rise and its first remotely-operated vehicle deployments along the Mid-Atlantic Ridge. It is currently capable of rapidly filtering 24 discrete large-watervolume samples (30-100 L per sample) for suspended particles during a single deployment (e.g. 490 L per sample at 4-7 L per minute through 1 mm pore diameter polycarbonate filters). The Suspended Particulate Rosette sampler has been designed with a long-term goal of seafloor observatory deployments, where it can be used to collect samples in response to tectonic or other events. It is compatible with in situ optical sensors, such as laser Raman or visible reflectance spectroscopy systems, enabling in situ particle analysis immediately after sample collection and before the particles alter or degrade.

A new tool was developed for large volume sampling to facilitate marine microbiology and biogeochemical studies. It was developed for remotely operated vehicle and hydrocast deployments, and allows for rapid collection of multiple sample types from the water column and dynamic, variable environments such as rising hydrothermal plumes. It was used successfully during a cruise to the hydrothermal vent systems of the Mid-Cayman Rise. The Suspended Particulate Rosette V2 large volume multi-sampling system allows for the collection of 14 sample sets per deployment. Each sample set can include filtered material, whole (unfiltered) water, and filtrate. Suspended particulate can be collected on filters up to 142 mm in diameter and pore sizes down to 0.2 μm. Filtration is typically at flowrates of 2 L min-1. For particulate material, filtered volume is constrained only by sampling time and filter capacity, with all sample volumes recorded by digital flowmeter. The suspended particulate filter holders can be filled with preservative and sealed immediately after sample collection. Up to 2 L of whole water, filtrate, or a combination of the two, can be collected as part of each sample set. The system is constructed of plastics with titanium fasteners and nickel alloy spring loaded seals. There are no ferrous alloys in the sampling system. Individual sample lines are prefilled with filtered, deionized water prior to deployment and remain sealed unless a sample is actively being collected. This system is intended to facilitate studies concerning the relationship between marine microbiology and ocean biogeochemistry.

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We have developed and are building a new oceanographic tool, a SUspended Particulate Rosette (SUPR) sampling system. The SUPR sampler is capable of rapidly filtering 25 large water volume samples (30 to 100 liters per sample) for suspended particulates during a single deployment. In addition, the SUPR sampler is designed to be compatible with in situ optical analysis methods. We are developing the SUPR sampler to investigate these fundamental questions, "How do ironand manganese-rich, hydrothermal plume particles affect seawater chemistry and to what extent do these paiticles fuel microbial activity in deep-sea hydrothermalplumes?" While past studies have determined the average chemical composition of hydrothermal plumes we lack the detailed information we need to understand the complete formation process and to what extent plume particle chemistry is modified by reactions with seawater and chemosynthetic organisms. Key to answering these questions is understanding the spatial and temporal variability of plume particle composition and mineralogy. Examination of this complex system requires the collection of numerous, spatiallydiscrete particle samples from hydrothermal plumes. Existing systems collect only a single combined sample -this has been the major obstacle to addressing our research questions.The SUPR sampler is designed to address this sampling need. It consists of a custom filtering head capable of sequentially collecting 25 discrete samples or 10 replicate pairs. This filtering head is interfaced with an 8 to 30 liter per minute pumping system. It can be deployed on a CTD rosette for spatially-discrete tow-yo sampling of non-buoyant hydrothermal plumes, on an ROV (e.g. Jason) for sampling rising plumes, or mounted on a fixed mooring in a hydrothermal vent field for time series sampling. In addition the SUPR sampler is designed with a long-term perspective for seafloor observatory deployments where it can be used to collect particulate samples as time series and in response to tectonic (or other) events. We see an increasing demand for this capabilityenabling both spatially-resolved and, importantly, temporallyresolved sampling of suspended particulates or microbes from a range of dynamic biogeochemical environments, not just hydrothermal systems. With such future applications in mind, and because many particle characteristics are short lived, the SUPR sampler has been designed to be compatible with in situ optical sensors based on visible and laser spectroscopy.

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