Use a core extruder to gently and slowly force core material out of the corer or core liner. If a core liner is used, visually inspect before extruding, sectioning, or slitting liner and core. Record features observed in field notes. Remove core catcher and check valve before extrusion process. Begin extrusion process from cutting end of barrel.
Vertical extrusion is recommended.
Note deformation and compaction. Note sloping layers, indicating possible nonperpendicular penetration of bottom. Note changes in stratigraphy, such as color and texture. Transfer only material that meets project and sampling objectives. If compositing core material or segments, follow procedures listed above for the grab sampler.