Drill cuttings

Drill cuttings refers to any material (typically called solids) removed from a borehole while drilling petroleum wells. Although sand and shale make up the majority of the cuttings encountered while drilling a well, depending on the location, any number of formations will actually be encountered. These include but are not limited to: anhydrite, calcite, coal chalk, chert, clay, dolomite, feldspar, glauconite, granite, gypsum, hematite, iron, kaolinite, lime, marlstone, mica, mudstone, pisolite, pyrite, quartz, sand, sandstone, shale, silica, silt and sulfur. Drill cuttings are usually removed by circulating the drilling fluid over shale shakers.

References

nl:Boorgruis