10.1594/PANGAEA.972120Khim, Boo-KeunBoo-KeunKhimPusan National UniversityKim, SunghanSunghanKim0000-0003-4245-8389Korea Polar Research InstituteAsahi, HirofumiHirofumiAsahi0000-0002-3803-7832Fukui Prefectural Satoyama-Satoumi Research InstitutePANGAEA2024biogenic opalearly PleistoceneGulf of AlaskaIODP 341Late MioceneU1417Event labelSample code/labelDEPTH, sediment/rockDepth, compositeOpal, biogenic silicaLithologic unit/sequenceDrilling/drill rigDSDP/ODP/IODP sample designationExp341Joides ResolutionIntegrated Ocean Drilling Program / International Ocean Discovery Program (IODP)2013-06-13T00:00:00/2013-06-17T00:00:00Dataset10.1029/2025GC01217310.2204/iodp.proc.341.103.20141764 data pointstext/tab-separated-valuesCreative Commons Attribution 4.0 InternationalInternational Ocean Discovery Program Site U1417 in the Surveyor (Gulf of Alaska) preserves the hemi-pelagic sediments influenced by the glacial and fluvi-al depositional from the Cordilleran Ice Sheet at the Chugach–St. Elias Mountains and Coast Ranges. A total of 441 samples covering the late Miocene to early Pleistocene were used to measure the biogenic opal content to trace the degree of diatom productivity in the surface water. In general, the biogenic opal content, fluctuating from less than 1% to a maximum of 48.6%, confirms the division of lithostratigraphic units and subunits: diatom-bearing clay-rich intervals vs clast-rich terrigenous intervals. The dataset presents Biogenic opal contents at U1417 from the Late Miocene to the Late Pleistocene, along with lithological units defined in the proceeding of IODP Expeition 341 (Jaeger et al., 2014). Biogenic opal contents at U1417 from the Late Miocene to the Late Pleistocene, along with lithological units defined in the proceeding of IODP Expeition 341 (Jaeger et al., 2014).-147.1099750000000256.95983Southern Alaska Margin