This voxel layer is the GeoTOP model from the Geological Survey of the Netherlands. This data shows the permeability of the ground.
Voxel layers can be used to visualize atmospheric or oceanic data, a geological underground model, or space-time cubes as voxel layers. You can use them to explore spatial relationships with other content by visualizing them together. For example, you might want to view an underground geological model with boreholes or construction that is planned in an area. Upcoming releases will add support for explorative tools and popups to inspect individual voxels, so the current use is for visualizing only.
For more information on voxel layers, please see the What is a voxel layer? help. Visualizing a voxel layer provides information on creating and sharing voxel scene layer packages (SLPKs). To understand how to manipulate your multidimensional data for voxel layers, please check this article describing a real use case from source data to voxel layer.
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