{"thcode":2,"term":{"code":2062,"name":"piston coring","parent":281,"scope":"Use of a piston mechanism and a weight with a triggering mechanism to drive a coring tube deep into underwater sediments for extraction and study."},"uf":[],"bt":[{"code":281,"name":"drilling and coring","parent":379,"scope":"Cutting into the subsurface, for example into underground strata, ice, or a tree trunk, to remove material for examination. Intended for broad use wherever coring is done. The combination of this term with other terms will convey the context of the activity."},{"code":379,"name":"field sampling","parent":376,"scope":"Collecting pieces or specimens or making measurements or observations at determined intervals or areas.  Results may be used as representative of the whole research area or population."},{"code":376,"name":"field methods","parent":734,"scope":"Research procedures and instrumental means to measure, collect data and samples, and observe in the natural areas where the materials, phenomena, structures, or species being studied occur."},{"code":734,"name":"methods","parent":1,"scope":"Techniques, methods, procedures, or strategies for research, management, collection, or analysis of scientific information in USGS."},{"code":1,"name":"Categories","parent":null,"scope":"Thematic terms for categorizing information resources.  This thesaurus is intended to support finding and understanding scientific information."}],"nt":[],"rt":[]}