A comparison was made between geologic, radiometric and paleomagnetic methods of dating and stratigraphic correlation on the Pribilof Islands of Alaska.[Reference: Cox, Allan, Hopkins, D.M., and Dalrymple, G.B., 1966, Geomagnetic polarity epochs, Pribilof Islands, Alaska: Geological Society of America Bulletin, v. 77, no. 9, p. 883-909.]

Data Type: Exxon Valdez Oil Spill; This database was developed to track daily shoreline assessments done by ADEC monitors following beach treatment. Data is referenced to beach segment and subdivision and includes treatment type, condition after treatment, oiling observed, equipment used, and names of agency representatives present. This database could be linked to ADEC's GIS system.

Data Type: Exxon Valdez Oil Spill; Shoreline oiling for spring 1991 at a scale of 1:63,360. GIS database produced as a result of the Exxon Valdez Oil Spill (EVOS) for Natural Resources Damage Assessment (NRDA). Data was collected under the supervision of the Alaska Department of Environment Conservation (ADEC) with the goal to map and monitor all know locations of beached oil. The 1990 shoreline oiling ADEC used low-altitude aerial observations. The scale is 1:63,360. The intended purpose of this database is to provide a resource for use in the oil spill damage identification, oil spill response, habitat restoration activities.

Data Type: Rivers/Streams; This hydrographic coverage was extracted from an image processing system that uses rivers from the Digital Chart of the World for georeferencing satellite images. The data have a scale of 1:1000000. The vectors pertaining to the greater Arctic Refuge and portions of Canada were extracted, rebuilt with line topology and projected into Albers Conic Equal Area projection.

Data Type: Exxon Valdez Oil Spill; The 1990 spring survey was conducted between March 23, 1990 and June 7, 1990. Surveys were conducted by representatives from the State of Alaska, U.S. Coast Guard, local landowners, and Exxon Corporation. Typical crew size was six members. The survey was intended to include all areas of shoreline oiling. Exxon provided for timely automation and delivery of these data. The intended use of this database is to provide a resource for use in the oil spill damage identification, oil spill response, habitat restoration activities.

Data Type: Oceans/Coasts; This is the most detailed digital coastline coverage which is currently available for the entire state.

Data Type: Vegetation/Land Cover/Soils; Pacific GIS used several different full resolution vegetation datasets organized by 1:250,000 scale USGS quadrangles to cover the Prince William Sound - Copper River ecosystem. Pacific GIS based this merged layer on the Chugach NF Timber Type data but augmented it with information from the Interim Land Cover layer in areas where there are holes in the Timber Type layer. Please refer to the documentation for veg_tt and veg_ifc for a complete discussion of datasets used to create this hybrid data layer.

Data Type: Freshwater Systems; This composite stream data layer covers the Prince William Sound and Copper River region. Pacific GIS developed this layer by merging data from the Chugach National Forest Channel Type database, the Alaska Department of Natural Resources (DNR) Exxon Valdez Oil Spill and Alaska Land and Resource Mapping Program databases, and the USGS Digital Line Graph (DLG) database. The most detailed stream coverage is for Prince William Sound and is taken largely from the Chugach NF Channel Type Database. Pacific GIS filled gaps in the Channel Type Database with stream information from the DNR Oil Spill Database. Stream data for areas outside Prince William Sound was drawn largely from the Alaska DNR ALARM Database. Data obtained from the USGS DLG data is very small scale (1:2,000,000 scale) and is suitable only for an overview of streams within the region. All stream data except that obtained from the Chugach NF Channel Type database include information on presence of anadromous fish, although this information is variable in age and not documented as to source. Related data layers include polygonal hydrologic features (hydro_pl)

Data Type: Minerals; Mineralized zones from U.S. Department of Interior Bureau of Mines including mineral identification and level of mineralization. Scale is 1:250,000.

This dataset contains the longitude lines which define the Alaska Coordinate System of 1927, state plane zones 1 through 10. The system of rectangular plane coordinates is established by the National Geodetic Survey, National Ocean Service, for defining and stating the positions of points on the surface of the earth for the state of Alaska.