The fate of carbon while passing through the rocky subseafloor of the ocean has direct implications on the global carbon cycle now and over geologic time, as well as the abundance and distribution of subseafloor life. Many organic geochemical studies require larger volumes of fluids than traditional hydrothermal samplers can provide, and also require rigorous steps to be taken to prevent contamination. The Hydrothermal Organic Geochemistry (HOG) sampler is designed to collect large volume (2–9 L) fluid samples with minimal introduction of organic or microbial contamination, and to be powered and deployed in real time from a submersible. Additional design constraints include utilizing materials appropriate for sampling fluids with elevated temperatures, fitting the sampler into the space available on the submersible, and minimizing the time needed to remove samples and prepare the sampler for re-deployment between dives. It utilizes two inlets, one devoted to natural abundance geochemistry and one that can be used for samples pre-dosed with isotopic labels or preservatives. Temperature probes providing real-time data are incorporated into each inlet to facilitate positioning the intake in areas of the hottest fluid flow, thereby minimizing entrainment of ambient bottom seawater while sampling. Fluids are shunted through two main conduits by a large volume pump. Smaller ports stemming off the main conduit connect to positive displacement fluid sample chambers and in situ filters. The outlets of these chambers and filter holders are connected to a 24-port valve, which in turn is connected to a small volume pump. The HOG sampler has successfully collected over 100 high purity fluid samples and 50 in situ filters during two expeditions to deep sea hydrothermal fields.

碳通过海洋的岩石海底时的命运直接影响着现在和整个地质时期的全球碳循环，以及海底生物的丰富和分布。许多有机地球化学研究要求的流体量比传统的水热采样器所能提供的流体大，并且还需要采取严格的步骤来防止污染。热液有机地球化学（HOG）采样器设计用于在不引入有机或微生物污染的情况下收集大体积（2–9 L）流体样品，并通过潜水器实时供电和部署。其他设计限制包括：利用适合于对高温流体进行采样的材料，将采样器安装到潜水器上可用的空间，并最大程度地减少了取出样品和准备取样器以在两次潜水之间重新部署所需的时间。它利用两个进样口，一个进样口用于自然丰度地球化学，一个进样口可用于预先添加了同位素标记或防腐剂的样品。提供实时数据的温度探头被集成到每个入口中，以方便将入口放置在最热的流体流区域，从而最大程度地减少采样时对周围底部海水的夹带。大型泵将流体通过两个主管道分流。从主导管上抽出的较小端口连接到容积式流体样品室和原位过滤器。这些腔室的出口和过滤器支架连接到24通阀，而24通阀又连接到小容量泵。