Enhancements to the OOI Cabled Array at Axial Seamount

海洋观测站倡议(OOI)的一部分是位于太平洋东北部的一个电缆观测站，该观测站近海延伸到轴海山，轴海山是一座活跃的海底火山，经常喷发，有热液喷发场和独特的深海生态系统。由于它是如此活跃和容易接近，轴海山一直是一个长期的研究地点，监测揭示了火山膨胀和通货紧缩的周期，这种周期被用来预测喷发的准确性越来越高。该项目将通过增加能够探测峰顶破火山口热液产出变化和火山地面运动的仪器，来加强轴海山的OOI电缆阵列，这反过来又将改善喷发预报。对轴海山监测工作的这些改进将有助于增进我们对活火山的岩浆储存系统、导致和触发喷发的过程以及海底喷发对热液系统及其维持的深海生态系统的影响的了解。教师将参与研究巡游以部署仪器，教师将在研究巡游之前、期间和之后与教室进行互动。在纽波特的哈特菲尔德海洋科学游客中心的公开讲座，或将包括该项目的结果。2015年的轴海火山喷发是OOI有线阵列首次实时探测到的。尽管它以前所未有的细节捕捉到了这一事件，但它也表明，仪器网络中缺少一些关键观测数据，限制了人们对火山喷发及其后果的了解。该项目将对有线观测站进行以下有针对性的、及时的补充：(1)一台新的海底CTD(电导率、温度、深度)仪器，用于增加临界盐度测量，目前尚缺乏这种仪器，但需要这些仪器来验证海底喷发期间从地壳释放热液卤水的假设，以及(2)已经建造并支付费用的一台海底压力/倾斜仪。此外，将建造四个自动(非电缆)微型压力记录器，并将购买一个声波释放换能器，用于现有的自动海底压力记录系泊设备。这些仪器将加强对海底火山变形的空间和时间监测，并加强对其地下成因的模拟。

Part of the Ocean Observatories Initiative (OOI) is a cabled observatory in the northeast Pacific Ocean that extends offshore to Axial Seamount, an active submarine volcano that has frequent eruptions, hydrothermal vent fields, and unique deep-sea ecosystems. Because it is so active and accessible, Axial Seamount has been a long-term study site and monitoring has revealed a cycle of volcano inflation and deflation that has been used to forecast eruptions with increasing accuracy. This project will enhance the OOI Cabled Array at Axial Seamount by adding instruments with the capability to detect changes in hydrothermal output in the summit caldera, and to ground movements at the volcano, which will in turn improve eruption forecasts. These enhancements to the monitoring effort at Axial Seamount will help to increase our understanding of magma storage systems at active volcanoes, the processes that lead to and trigger eruptions, and the impacts of submarine eruptions on hydrothermal systems and the deep-sea ecosystems they sustain. A teacher will participate on the research cruise to deploy the instruments, and the teacher will interact with classrooms before, during, and after the research cruise. Public lectures at the Hatfield Marine Science Visitor Center in Newport, OR will include results from this project. The 2015 eruption at Axial Seamount was the first detected in real time by the OOI Cabled Array. Although it captured the event in unprecedented detail, it also showed that there are some key observations missing from the instrument network that limited understanding of the eruption and its consequences. This project will make the following targeted and timely additions to the cabled observatory: (1) one new seafloor CTD (Conductivity, Temperature, Depth) instrument to add critical salinity measurements, which are currently lacking but are needed to test the hypothesis that hydrothermal brine is released from the crust during seafloor eruptions, and (2) one bottom pressure/tilt instrument that has already been built and paid for. In addition, four autonomous (non-cabled) miniature pressure recorders will be built and an acoustic release transducer will be purchased to be used on an existing autonomous bottom pressure recording mooring. These instruments will enhance the spatial and temporal monitoring of volcanic deformation of the seafloor and the modeling of its causes in the subsurface.