Eckerd College 1 article published in JoVE Chemistry Sediment Core Extrusion Method at Millimeter Resolution Using a Calibrated, Threaded-rod Patrick T. Schwing1, Isabel C. Romero1, Rebekka A. Larson2, Bryan J. O'Malley1, Erika E. Fridrik1, Ethan A. Goddard1, Gregg R. Brooks2, David W. Hastings2, Brad E. Rosenheim1, David J. Hollander1, Guy Grant1, Jim Mulhollan1 1College of Marine Science, University of South Florida, 2Marine Science and Chemistry, Eckerd College An extrusion method using a calibrated threaded-rod is presented, which allows for mm scale subsampling of aquatic sediment cores. Millimeter-scale sampling is necessary to fully characterize recent event stratigraphy in sediment records.