In this slice of sandstone there are many gaps between the sand grains, making the rock porous. As the gaps are connected, the sandstone is also permeable: any liquid or gas held in the rock can move through it. Rocks that are both porous and permeable are ideal reservoirs for storing oil and gas underground.
Using this item
Photograph by Nick Mortimer
Permission of GNS Science must be obtained before any use of this image.