Water column geochemistry data from REVOSIMA MAYOBS15 Cruise

the mayotte volcanological and seismological monitoring network (revosima) was created in response to the sub-marine eruption that started in may 2018. composed by ipgp, brgm, ifremer and cnrs, its main missions are: 1) to observe and study volcanic phenomena through real-time volcano monitoring, 2) to conduct research programs, 3) to communicate, disseminate and inform authorities and civil society.these real-time observations and research can contribute to the prevention, and mitigation of seismic and volcanic risks. the main objective is to collect geological, geophysical and geochemical data over long periods of time to improve the understanding and modeling of volcanic processes at active volcanoes, to allow the systematic elaboration of long-term multi-parameters databases available to the scientific community, and to inform the authorities in charge of civil protection of any change in the volcano activity and after periods of local and regionally felt earthquakes.the mayobs campaigns are carried out to monitor the evolution of the seismic and volcanic phenomenon which has affected the island of mayotte since may 2018. they are carried out as part of an action program financed by the ministry of research, the general directorate of prevention and risks of the ministry of ecological and inclusive transition, with the support of the interministerial delegate for major risks overseas and in conjunction with the other ministries and institutes involved (ipgp, ipgs, brgm, ifremer). they focus on the region east of mayotte. the bathymetric surveys carried out by shom in the volcano area also contribute to the mayobs project.ifremer carried out water column geochemistry measurements during md242 / mayobs25 cruise. in the present database, 9 stations were investigated between the 6th and 22nd october 2020 using in situ measurements embedded in a ctd-rosette. samples (max. 16 bottles per station) were anaylized onboard and onshore depending on the parameters. the quality controlled and process data are: in situ: salinity (conductivity), temperature, depth, dissolved oxygen, turbidity onboard: ph, alkalinity, dissolved inorganic carbon, dissolved ch4 co2 h2 onshore: silicates, d13c ch4, d13c co2, he, ne, 3he, 4he

为应对2018年5月开始的海底火山喷发，马约特火山地震监测网络（Revosima）应运而生。该网络由法国国家地球物理研究所（IPGP）、法国地质与矿业研究所（BRGM）、法国海洋研究发展研究所（IFREMER）及法国国家科学研究中心（CNRS）共同组成，其主要任务包括：1）通过实时火山监测，观察和研究火山现象；（2）开展研究项目；（3）向政府和民间社会传达、传播和提供信息。这些实时观测和研究有助于预防和减轻地震及火山风险。其主要目标是长期收集地质、地球物理和地球化学数据，以提升对活跃火山火山过程的理解和建模，允许科学界系统地编制长期多参数数据库，并向负责民防的当局通报火山活动及其后的局部和区域性地震活动变化。马约特观测（Mayobs）活动旨在监测自2018年5月起影响马约特岛的地震和火山现象的演变。这些活动作为由研究部、生态包容性转型部预防与风险总司资助的行动计划的一部分实施，得到海外重大风险部际代表的支持，并与相关部门（IPGP、IPGS、BRGM、IFREMER）合作。它们专注于马约特岛东部地区。法国海洋水文局（SHOM）在火山区域进行的海洋地形测量也为马约特观测项目做出了贡献。在MD242/马约特25巡航期间，IFREMER进行了水柱地球化学测量。在当前数据库中，2020年10月6日至22日间，利用嵌于CTD-罗斯特（CTD-Rosette）中的原位测量，对9个站点进行了调查。每个站点的样品（最多16瓶）根据参数在船上和岸上进行分析。质量控制和处理数据包括：原位：盐度（电导率）、温度、深度、溶解氧、混浊度；船上：pH值、碱度、溶解无机碳、溶解甲烷、二氧化碳、氢气；岸上：硅酸盐、碳同位素D13C、甲烷、二氧化碳、氦、氖、三氦、四氦。