Motion and pressure data recorded with Benthic Event Detectors (BEDs) in Monterey Canyon, offshore California

Benthic Event Detectors (BEDs) were placed in Monterey Canyon as part of the Monterey Canyon Coordinated Canyon Experiment (CCE). The CCE was set up to measure the passage of sediment gravity flows down Monterey Canyon. BEDs are "smart boulders" that record time-stamped acceleration, rotation, and ambient pressure data. Each BED device is a 43 cm diameter sphere with 1.8 g/cc density in air, weighing 81.5 Kg in air and 35 Kg in water. The experimental design of the CCE called for having BEDs on the canyon floor at 200, 300 and 400 m water depth. Within logistical constraints, after BEDs moved during sediment flows, these depths were repopulated with newly-deployed BEDs. A total of 11 BEDS and two AMT/BED deployments took place during the CCE. BEDs deployed multiple times are denoted with A, B and C for each deployment. CU indicates a cubic-shaped bed. BED deployment locations are listed under the station Acquisition Information tab. There are two types of data files presented here. The pressure data file, called MBCCE_BED_Depths_Time.xlsx, is an Excel spreadsheet that includes tide-adjusted depth of the BEDs during sediment gravity flows. The rotational data files are Excel spreadsheets that contain the raw quaternion data recorded by the inertial motion unit once the BED started to move due to the arrival of a sediment gravity flow. The four columns in each of the rotational data files are the quaternion components: quaternion component 1 (rotation angle parameter), quaternion component 2 (vector coordinate), quaternion component 3 (vector coordinate), and quaternion component 4 (vector coordinate). BED rotational data retrieved wirelessly from BEDs deployed on the seafloor have a sample resolution of 5 samples per second. The resolution of rotational data from BEDs that were physically recovered is 50 samples per second, except for BED05. Pressure changes were recorded 5 seconds after the initiation of motion. Thus, there is no depth information for the first 5 seconds of rotational motion. The rotational data file names are structured as BED ID_date of event (yyyymmdd)_sampling rate (5 Hz or 50 Hz)_optional (segment of the event or none if full event). For additional information about the BEDs, review the "Science Report" and download the file "CCE BED Deployment Locations" under the Documents tab. Funding for the project was provided by The David and Lucile Packard Foundation, Natural Environment Research Council (NE/K011480/1), U.S. Geological Survey, Ocean University of China, and Qingdao National Laboratory for Marine Science and Technology.

底栖事件探测器（Benthic Event Detectors，BEDs）作为蒙特雷峡谷协同峡谷实验（Coordinated Canyon Experiment，CCE）的一部分，被部署于蒙特雷峡谷中。该实验旨在监测沉积物重力流沿蒙特雷峡谷的运移过程。BEDs属于"智能巨石"，可记录带时间戳的加速度、旋转姿态与环境压力数据。单台BED设备为直径43厘米的球形装置，空气中密度为1.8 g/cc（克每立方厘米），空气中重量为81.5千克，水中重量为35千克。CCE的实验设计要求在水深200米、300米与400米的峡谷底部署BEDs。受后勤条件限制，当BEDs在沉积物重力流活动中发生位移后，研究团队会重新在对应水深位置部署新的BEDs以补足测点。本次CCE期间共计开展了11次BEDs部署与2次AMT/BED联合部署。多次部署的BEDs会以A、B、C分别标记其不同部署批次。CU标记的为立方形状的探测装置。BEDs的部署位置可在「测点采集信息」标签页下查看。本次公开的数据文件共分为两类。压力数据文件名为MBCCE_BED_Depths_Time.xlsx，为Excel表格格式，记录了沉积物重力流活动期间BEDs经过潮汐校正后的水深数据。旋转姿态数据文件同样为Excel表格格式，存储了BEDs因沉积物重力流抵达而发生位移时，惯性运动单元记录的原始四元数数据。每份旋转姿态数据文件均包含四列数据，对应四元数的四个分量：四元数分量1（旋转角度参数）、四元数分量2（矢量坐标）、四元数分量3（矢量坐标）与四元数分量4（矢量坐标）。通过无线方式从海底部署的BEDs中获取的旋转姿态数据，采样分辨率为每秒5个样本。通过物理回收获取的BEDs旋转姿态数据，采样分辨率为每秒50个样本，BED05除外。压力变化数据会在运动启动5秒后开始记录，因此旋转姿态数据的前5秒无对应水深信息。旋转姿态数据文件的命名格式为：BED编号_事件日期（格式为yyyymmdd）_采样率（5 Hz或50 Hz）_可选字段（事件片段，若为完整事件则无此字段）。如需获取BEDs的更多相关信息，请查阅"Science Report"，并在「文档」标签页下下载文件"CCE BED Deployment Locations"。本项目的资助方包括大卫与露西·帕卡德基金会、自然环境研究委员会（编号NE/K011480/1）、美国地质调查局、中国海洋大学以及青岛海洋科学与技术试点国家实验室。