Small and large particle concentrations of total carbon, total nitrogen, and inorganic carbon, and particulate thorium-234 and RAP234 from large volume pump profiles collected on R/V Endeavor cruise EN665 in the Gulf of Maine in April 2021

Sample collection took place at two primary stations within the Gulf of Maine's Wilkinson and Jordan basins from the R/V Endeavor in April 2021. McLane pumps were deployed at eight depths throughout the water column from near the sea surface (~14 meters) to near the seafloor (~250 meters). The first deployment occurred in the Wilkinson Basin and the second occurred in the Jordan Basin. Small (1-51 micrometer (µm)) and large particle (>51 µm) concentrations of total carbon, total nitrogen, and inorganic carbon (PC, PN, and PIC, respectively) are presented, along with small particle isotopic compositions (13C, 15N) of these phases, particulate thorium-234, and RAP234 (a resuspension proxy associated with particulate thorium-234). Depth profiles demonstrate typical particulate carbon shapes. The PIC demonstrates a peak near the seafloor, indicating the potential presence of a nepheloid layer. This feature does not appear in the PC data. The isotopic composition of the PIC demonstrates uniquely negative values throughout the water column. Small particle thorium-234 activities were consistently larger than the large particle activities at all depths and small particle RAP234 activities indicate possible resuspension in the bottom ~50 m of the water column. These data were collected by Drs. Adam Subhas (WHOI) and Erin Black (UR). Data processing and preparation were completed by Dr. Subhas, Dr. Black, and Karine Holmes (UR).

本数据集的样品采集工作于2021年4月依托“奋进号”（R/V Endeavor）科考船，在缅因湾（Gulf of Maine）的威尔金森盆地（Wilkinson Basin）与约旦盆地（Jordan Basin）两个主要站位开展。研究团队采用麦克莱恩泵（McLane pumps），在全水柱范围内设置8个采样深度，覆盖范围从近海面（约14米）至近海底（约250米），其中首次采样部署于威尔金森盆地，第二次部署于约旦盆地。本数据集包含细颗粒（1~51 µm）与粗颗粒（>51 µm）的总碳（total carbon）、总氮（total nitrogen）及无机碳（inorganic carbon，分别对应PC、PN、PIC）浓度数据，同时涵盖上述组分的细颗粒同位素组成（13C、15N）、颗粒态钍-234（particulate thorium-234）以及RAP234——一种与颗粒态钍-234相关的再悬浮替代指标——的相关数据。深度剖面呈现出典型的颗粒碳分布形态。无机碳颗粒（PIC）在近海底区域出现浓度峰值，指示研究区域可能存在雾状层（nepheloid layer），但该特征并未在细颗粒总碳（PC）数据中体现。全水柱范围内的PIC同位素组成均呈现出独特的负值特征。各采样深度下，细颗粒态钍-234的活度始终高于粗颗粒态钍-234；细颗粒态RAP234活度则指示水柱底部约50米范围内可能存在沉积物再悬浮现象。本数据集由亚当·苏巴斯博士（Adam Subhas，WHOI）与艾琳·布莱克博士（Erin Black，UR）完成样品采集，数据处理与整理工作由苏巴斯博士、布莱克博士以及卡琳·霍姆斯（Karine Holmes，UR）共同完成。