s1c08sc_video_observations

This part of DS 781 presents video observations from cruise S1C08SC for the Santa Barbara Channel region and beyond in southern California. The vector data file is included in "s1c08sc_video_observations.zip," which is accessible from http://pubs.usgs.gov/ds/781/video_observations/data_catalog_video_observations.html. Some of the video observations from cruise S1C08SC are published in Scientific Investigations Map 3225, "California State Waters Map Series--Hueneme Canyon and Vicinity, California" (see sheet 6). In addition, some of the video observations will be published in eight future California State Waters Map Series SIMs of the region (namely, the Mugu Canyon and Vicinity, Offshore of Ventura, Offshore of Carpinteria, Offshore of Santa Barbara, Offshore of Coal Oil Point, Offshore of Refugio Beach, Offshore of Gaviota, and Offshore of Point Conception map areas) [note that, at the time of this writing, two of the other eight SIMs have been published: the Offshore of Ventura map area (SIM 3254), and the Offshore of Carpinteria map area (SIM 3261)]. Between 2006 and 2007, the seafloor in the Mugu Canyon and Vicinity, Hueneme Canyon and Vicinity, Offshore of Ventura, Offshore of Carpinteria, Offshore of Santa Barbara, Offshore of Coal Oil Point, Offshore of Refugio Beach, Offshore of Gaviota, and Offshore of Point Conception map areas in southern California was mapped by California State University, Monterey Bay, Seafloor Mapping Lab (CSUMB) and by the U.S. Geological Survey (USGS), using both multibeam echosounders and bathymetric sidescan sonar units (for example, see sheets 1, 2, and 3, SIM 3225, for details). These mapping missions combined to collect bathymetry and acoustic-backscatter data from about the 10-m isobath to out beyond the 3-nautical-mile limit of California's State Waters. To validate the interpretations of sonar data in order to turn it into geologically and biologically useful information, the USGS ground-truth surveyed the data by towing camera sleds over specific locations throughout the region. During the 2008 ground-truth cruise, the camera sled housed two video cameras (one forward looking and the other vertical looking), a high-definition video camera, and an 8-megapixel digital still camera. The video was fed in real time to the research vessel, where USGS and NOAA scientists recorded both the geologic and biologic character of the seafloor into programmable keypads once every minute. In addition to recording the seafloor characteristics, a digital still photograph was captured once every 30 seconds. This ArcGIS shape file includes the position of the camera, the time each observation was started, and the visual observations of geologic and biologic habitat.本数据集DS 781的此部分收录了针对加利福尼亚南部圣巴巴拉海峡及周边海域的S1C08SC航次视频观测数据。矢量数据文件打包于"s1c08sc_video_observations.zip"压缩包中，可通过链接http://pubs.usgs.gov/ds/781/video_observations/data_catalog_video_observations.html获取。 部分S1C08SC航次的视频观测数据已发表于《科学调查图集（Scientific Investigations Map）3225：加利福尼亚州水域图集系列——加利福尼亚州休尼梅峡谷及周边区域》（参见第6幅图幅）。此外，部分视频观测数据将刊载于该区域后续的8幅加利福尼亚州水域图集系列科学调查图集（SIMs），覆盖区域分别为：穆古峡谷及周边、文图纳近海、卡皮特里亚近海、圣巴巴拉近海、科伊尔角近海、雷富吉奥海滩近海、加维奥塔近海以及康塞普西翁角近海海域【注：本文撰写时，8幅待刊图集中已有2幅正式刊行：文图纳近海图集（SIM 3254）与卡皮特里亚近海图集（SIM 3261）】。 2006年至2007年间，加利福尼亚州立大学蒙特雷湾分校海底测绘实验室（CSUMB）与美国地质调查局（U.S. Geological Survey, USGS）采用多波束回声测深仪（multibeam echosounders）及测深侧扫声呐设备（bathymetric sidescan sonar units），对加利福尼亚南部上述8幅图集覆盖的海底区域开展了测绘工作（详细信息参见科学调查图集3225的第1、2、3幅图幅）。本次联合测绘任务采集了从约10米等深线（isobath）至加州州属水域3海里界限以外区域的水深测量数据（bathymetry）与声学背散射数据（acoustic-backscatter data）。为验证声呐数据解译结果，将其转化为具备地质与生物学应用价值的信息，美国地质调查局开展了地面验证调查：在区域内指定点位拖曳摄像雪橇进行实地观测。在2008年的地面验证航次中，摄像雪橇搭载了两台摄像机（一台朝前拍摄，一台垂直向下拍摄）、一台高清摄像机以及一台800万像素数码相机。视频信号被实时传输至研究船，美国地质调查局与美国国家海洋和大气管理局（NOAA）的科研人员每分钟通过可编程键盘记录一次海底的地质与生物特征。除记录海底特征外，系统还每30秒拍摄一张数码静态照片。本ArcGIS形状文件包含了摄像机位置、每次观测的起始时间以及地质与生物栖息地的目视观测结果。