GAK_Q39.TIF - Gulf of Alaska U.S. EEZ GLORIA sidescan-sonar data mosaic (9 of 30) (LCC, 50 m, WGS84)

GLORIA data for the Gulf of Alaska Exclusive Economic Zone (EEZ) were acquired during five cruises over a four year period. The first cruise conducted in 1986 (F-1-86-GA) surveyed an area of the north-central mosaic area and covered an area of approximately 40,000 square kilometers (sq km). The second two cruises (F-8-88-AA, F-9-88-WG) were conducted in 1988. One of the 1988 cruises (F-8-88-AA) focused on a survey of the Aleutian Arc. The eastern most portion of that survey extended outside of the Aleutian Arc survey area and covered an area of approximately 52,000 square kilometers (sq km) of seafloor on the western edge of the Gulf of Alaska. The final two cruises (F-6-89-GA, F-7-89-EG) were completed in 1989. As in earlier EEZ reconnaissance surveys, the USGS utilized the GLORIA (Geological LOng-Range Inclined Asdic) sidescan-sonar system to complete the geologic mapping. The collected GLORIA data were processed and digitally mosaicked to produce continuous imagery of the seafloor. Thirty digital mosaics with a 50-meter pixel resolution were completed for the region.阿拉斯加湾专属经济区（Exclusive Economic Zone，EEZ）的GLORIA数据，系在四年间的五次科考航次中采集所得。首次航次于1986年实施（编号F-1-86-GA），测绘了北中部镶嵌区域，覆盖面积约4万平方千米。1988年共开展两次航次（F-8-88-AA、F-9-88-WG），其中F-8-88-AA航次以阿留申弧（Aleutian Arc）测绘为核心任务，该航次的最东端测绘范围延伸至阿留申弧测绘区之外，覆盖了阿拉斯加湾西缘约5.2万平方千米的海底区域。1989年完成最后两次航次（F-6-89-GA、F-7-89-EG）。与早期专属经济区普查航次一致，美国地质调查局（USGS）采用GLORIA（Geological LOng-Range Inclined Asdic）侧扫声呐（sidescan-sonar）系统完成地质填图工作。所采集的GLORIA数据经处理与数字镶嵌，生成了连续的海底影像。该区域共计完成30幅像素分辨率为50米的数字镶嵌影像。