Major and trace element chemistry of volcanic tephra deposits at IODP Expedition 341 sites U1417 and U1418 (Gulf of Alaska)

During and after International Ocean Discovery Program (IODP) Expedition 341 to the Gulf of Alaska, >100 macroscopic volcanic glass-rich tephra deposits were identified in the scientific marine drill cores recovered at Sites U1417 and U1418. After confirmation using smear slide optical analysis techniques, bulk sediment samples were collected, the glass shards were concentrated, and prepared as grain-mount thin sections for in situ geochemical characterization using electron probe microanalyzer (EPMA) and laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) methods. This data release contains the following major element concentrations for 178 tephra layers from IODP Expedition 341 Sites U1417 and U1418: Na2O, MgO, Al2O3, SiO2, P2O5, Cl, K2O, CaO, TiO2, MnO, FeOt. It also contains the following trace element concentrations for 44 tephra layers: Li, P, Ca, Sc, Ti, V, Mn, Cu, Zn, Rb, Sr, Y, Zr, Nb, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Er, Yb, Hf, Ta, Pb, Th, U. Major and trace element data can be linked to samples, and their metadata, using IGSN numbers. We also provide concentrations for standard reference materials analyzed during analytical sessions as well as tables reporting their overall accuracy and precision.