Vestfold Hills 1:25000 Topographic GIS Dataset

Full description

The Vestfold Hills Topographic GIS Dataset includes features along the Ingrid Christensen Coast, Antarctica from the Sorsdal Glacier to the Wyatt Earp Islands.
Feature types include coastline, contours (5 metre interval), hypsometric areas, spot heights, cliffs, crevasses, water bodies, areas of exposed rock, moraines, dykes, areas of blue ice, glacier flow lines, drift tails, ice cracks and penguin colonies.
The data were originally formatted according to the Australian Antarctic Spatial Data Model and are included in the GIS data for the Vestfold Hills available for download from a Related URL.
The data has been reformatted according to the SCAR Feature Catalogue which superseded the Australian Antarctic Spatial Data Model.
Data that are part of this dataset have Dataset_id = 54 in the SCAR Feature Catalogue format.
Data quality information for each feature is located in the attribute table.

Lineage

Progress Code: completed

Statement: This dataset was originally compiled from 1:45000 scale aerial photography flown on 2/11/1994 (film ANTC 1011) and 10/4/1996 (film ANTC1030). The photography was done using a Zeiss UMK camera. The value tests for the dataset included a test for spatial accuracy and data completeness, including line and polygon errors. The layers were also checked to ensure that they overlaid and abutted as appropriate. A test of valid features against the Australian Antarctic Spatial Data Model and a visual check against all hard copy material were also carried out. Horizontal accuracy of well defined features was estimated to be better than 2 metres. Vertical accuracy of spot heights was estimated to be better than 1 metre. Vertical accuracy of contours was estimated to be better than 2 metres. Contour elevation errors in excess of 1 contour interval are known to exist on the southern margin of the dataset, specifically over the Sorsdal Glacier. April 1998 - March 1999 ----------------------- The dataset was updated from 1:45000 scale aerial photography flown on 11/2/1997 (film ANTC 1045). The photography was done using a Zeiss UMK camera. The updating was done for areas that were snow free when the 1997 photography was flown. Plotting was done at 1:25000. All lake boundaries and the entire coastline were mapped. All other exposed visible listed features, which had been previously covered by snow and ice, in the vicinity of the Vestfold Hills were captured. Features include boundaries of exposed rock, scree, continental ice, rock and ice cliffs, streams, lakes, melt lakes, melt streams, refuges, ridge lines, spot heights and snow covered areas. The February 1997 photography was controlled from previous photography obtained in November 1994 and April 1996. Photo Control accuracy varies between regions but is all better than 3 metres. The data were captured using a Zeiss P2 analytical stereo plotter and Microstation version 5 on a Universal Transverse Mercator grid. The polygon data were edited, cleaned and polygonized using Arc/Info. Maximum fuzzy tolerance for cleaning was 0.01 metres. The data were also generalised using a tolerance of 0.1 metres. The value tests for the dataset include a test for spatial accuracy and data completeness, including line and point errors a test of valid values against the data model a visual check to hard copy material plus or minus 2.5 metres. The horizontal accuracy of the updated features (Qinfo = 115) was estimated to be 12 metres. 2001 ---- Aerial photography flown in 2/11/1994 (ANTC1011, ANT1012) and 11/2/1997 (ANTC 1045) was used for further mapping and edits of the dataset. Plotting was done at 1:25000. The coastline on the Sorsdal Glacier was remapped using both 1994 and 1997 aerial photography. The coastline of Four islands off the coast of the Sorsdal Glacier were remapped using 1997 aerial photography due to the limited amounts of snow and ice coverage. The coastline in Tryne Bay was remapped using 1994 aerial photography. The 5 metre contour was adopted as the coast along the Sorsdal Glacier in areas where the 5 metre contour overlapped the remapped coastline. A new extent line was provided by the Australian Antarctic Data Centre. After the remapping of the coastline, existing continental Ice, crevasse field, glacier tongue, water body, moraine and snow features were merged with the new coastline to create a new Topopoly dataset. The remaining areas on land not covered by the existing features from the Topopoly dataset were classified as rock. Using 1997 (ANTC 1045) aerial photography: the water bodies were remapped in five different areas, including near the Sorsdal Glacier; some ice cliff features were added to the dataset; the contours were remapped in five areas and on four islands off the coast of the Sorsdal Glacier; additional dykes were mapped. All remapping work was captured using a Zeiss P2 analytical stereo plotter and Microstation version 5 on a Universal Transverse Mercator grid. The polygon data were edited, cleaned and polygonized using Arc/Info. Maximum fuzzy tolerance for cleaning was 0.01 metres. The data were also generalised using a tolerance of 0.1 metres. Polygon attributes were assigned using arc attributes in ArcView. The value tests for the dataset include a test for spatial accuracy using GPS data supplied by the Australian Antarctic Data Centre, a test for data completeness including line and point errors, a test of valid values against the Australian Antarctic Spatial Data Model by sampling features and checking against the model, and a visual check to hard copy material. All attributes (feature classifications and elevations) were derived from the aerial photography. The horizontal accuracy of the updated line features was estimated to be 12m and the vertical accuracy 5m, except for where: (i) contours were edited to correct intersections, the accuracy is variable; (ii) the 5 metre contour was adopted as the coast along the Sorsdal Glacier, the horizontal accuracy is that of the contour line features. Note: In mid 2014, 4 rock polygons were updated. These polygons were found to have overlap with the coastline and were clipped to the coastline. These were located at 78 degrees 19'50"E 68 degrees 26'7"S, 78 degrees 16'5"E 68 degrees 25'55"S, 78 degrees 17'55"E 68 degrees 26'22"S, 78 degrees 21'19"E 68 degrees 26'43"S, 78 degrees 22'2"E 68 degrees 26'43"S, 78 degrees 23'8"E 68 degrees 26'0"S