 The dissolved organic carbon, DOC, and volatile fatty acid, VFA, levels in marine sediments are affected by microbial activity, which can be observed through the mixing of seawater and deep-sourced fluids in a subsurface environment. This study used a submarine mud volcano, SMV, to examine the distribution of DOC in VFA levels and sediments and found that bulk DOC concentrations fluctuate with depth likely due to insidium microbial processes. Additionally, lactate, formate, acetate, propionate, and butyrate were detected in some samples, while acetate and formate concentrations were consistent in uniform throughout the biogeochemical zones, indicating that these compounds are being actively utilized and broken down by microorganisms. Furthermore, numerical modeling suggested that the majority of DOC patterns were primarily influenced by in situ organic matter degradation, while the impact of upward migrating fluid becomes more significant at center sites. This article was authored by Nichen Chen, Nichen Chen, Tsanio Frank Yang, and others. We are article.tv, links in the description below.