A portable extruder for accurate and precise high-resolution subsampling of unconsolidated sediment cores

We developed a portable extruder for precise and accurate high-resolution subsampling of unconsolidated sediment cores. This extruder is capable of producing subsamples at a minimum 1-mm resolution and is designed for easy operation and maintenance in the field. Movement of the threaded extruder rod (½” 8 start acme thread) through the core barrel is driven by a crank wheel graduated in 1-mm increments. This extruder design is particularly useful for obtaining incremental subsamples for applications where high-resolution subsamples of identical size are required (e.g. time series analysis, climate variability, land use change, contamination), and for use in field settings where it is impractical to deploy a freeze corer.