Raster Data
GIS data represented as a grid of cells (pixels), used for continuous surfaces like elevation, satellite imagery, and geological data.
Detailed Definition
Raster data is a type of GIS data that represents geographic information as a regular grid (matrix) of cells or pixels, where each cell contains a value representing a measurement or classification at that location. It is used for continuous surfaces and imagery.
Raster data characteristics: - Data organized in rows and columns of cells (pixels) - Each cell has a defined size (spatial resolution) - Each cell contains one or more values (bands) - Cell values can represent continuous (elevation, temperature) or categorical (land use, geology) data - Coordinate system defines the geographic position of the grid
Common raster data types
Elevation data: - Digital Elevation Models (DEMs) - Digital Terrain Models (DTMs) - Digital Surface Models (DSMs) - Used for slope, aspect, and viewshed analysis
Satellite imagery: - Multispectral imagery (Landsat, Sentinel) - High-resolution imagery (WorldView, Planet) - Radar imagery (SAR) - Used for land cover, change detection, and mineral mapping
Derived surfaces: - Geochemical interpolation grids - Geophysical survey data (magnetics, gravity) - Grade models and ore body surfaces - Mineral prospectivity maps
- GeoTIFF: Most common georeferenced raster format
- JPEG2000: Compressed imagery format
- Esri Grid: Esri proprietary raster format
- Cloud Optimized GeoTIFF (COG): Optimized for web access
- NetCDF/HDF: Scientific data formats
Applications in mining: - Terrain analysis for mine site planning - Satellite-based mineral alteration mapping - Volumetric calculations for stockpiles and excavations - Environmental baseline documentation - Grade modeling and resource estimation
Related Terms
GIS
Geographic Information System - software and technology for capturing, storing, analyzing, and displaying geographically referenced data.
Spatial Data
Data that describes the location, shape, and relationship of geographic features, including vector and raster formats.
Vector Data
GIS data representing geographic features as points, lines, and polygons with associated attributes, used for discrete features.
DEM
A Digital Elevation Model -- a digital representation of ground surface topography stored as raster data, used for terrain analysis and visualization.