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    A small ice cap (covering about 12 square kilometers) and at least two-probably four- cirque glaciers (each covering less than 1 square kilometer) occurred on St. George Islands, Pribilof Islands, probably during the Illinoian Glaciation, Snowbanks persisted during a later cold cycle, probably during the Wisconsin Glaciation with no glaciers existing. We found no evidence of glaciation on other Pribilof Islands.[Reference: Hopkins, D.M., and Einarsson, Thorleifur, 1966, Pleistocene glaciation on Saint George, Pribilof Islands: Science, v. 152, no. 3720, p.343-345.]

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    The National Oceanic and Atmospheric Administration's Ocean Environment Research Division established a geographic information system (GIS) for integrating multidisciplinary oceanographic data collected throughout the eastern North Pacific Ocean. Data collected by remote-sensing techniques include satellite imagery of sea surface temperature, seafloor bathymetry derived from multibeam sonar systems, and environmental acoustic signals from bottom-mounted and portable hydrophone arrays. Acoustic monitoring is directed at the detection and location of water-borne signals of seafloor earthquakes (T-waves) and whales. Field observations include seafloor geologic mapping and whale sightings. Seafloor mapping information is gathered using submersibles, towed-camera systems, and other towed water-sampling devices. A GIS allows the integration and analysis of these diverse and various spatial data and formats within a single computer architecture accessible through an easy-to-use graphical user interface. The GIS system described here has combined earthquake-source parameter information with acoustic locations and seafloor bathymetric data to provide new tectonic models of NE Pacific oceanic plate boundaries. Similarly, whale locations are mapped and compared to oceanographic features such as bathymetry and sea surface temperatures using GIS.