/* DATA DESCRIPTION: Citation: Ota, Hayu; Kuroda, Junichiro; Orihashi, Yuji; Schmitz, Mark D; Takashima, Reishi (2026): Major element compositions of the sample series KWR4 from the Kawaruppu section [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.994131 Abstract: This dataset contains major element compositions of the KWR4 sample series collected from the high-resolution interval of the Kawaruppu section, Nemuro Group, Hokkaido, Japan. These data were obtained to evaluate whether the osmium isotope ratios and platinum group element concentrations of the same samples were affected by diagenetic alteration. Major element compositions were measured by a RIGAKU ZSX Primus II X-ray fluorescence (XRF) spectrometer at Atmosphere and Ocean Research Institute (AORI), the University of Tokyo (Kashiwa). Keyword(s): Cretaceous-Paleogene boundary; East Asia; IODP³; Osmium; zircon U-Pb geochronology Supplement to: Ota, Hayu; Kuroda, Junichiro; Hayashi, Keiichi; Hoshi, Hiroyuki; Sawada, Ken; Hosogaya, Kohei; Nishi, Hiroshi; Ishikawa, Akira; Suzuki, Katsuhiko; Ikeda, Masashi A; Orihashi, Yuji; Schmitz, Mark; Gyawali, Babu Ram; Matsumoto, Hironao; Takashima, Reishi (2026): The Chicxulub impact signature in East Asia. Communications Earth & Environment, https://doi.org/10.1038/s43247-026-03602-z Funding: Japan Society for the Promotion of Science (JSPS) (URI: https://www.jsps.go.jp/english/), grant/award no. 17K05674: High resolution age model and paleoenvironmental change for K/Pg boundary (URI: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17K05674/) Japan Society for the Promotion of Science (JSPS) (URI: https://www.jsps.go.jp/english/), grant/award no. 18KK0091: Improvement of Cretaceous Geologic Time Scale (URI: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-18KK0091) Japan Society for the Promotion of Science (JSPS) (URI: https://www.jsps.go.jp/english/), grant/award no. 21H04503: Environmental changes during the Latest Cretaceous Mass Extinction Event recorded in the complete K/Pg boundary sequence discovered firstly in East Asia (URI: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-21H04503) Japan Society for the Promotion of Science (JSPS) (URI: https://www.jsps.go.jp/english/), grant/award no. 22H01342: The Cretaceous-Paleogene Boundary in the Southern Hemisphere: Osmium isotopic record to fingerprint flood basalt volcanism (URI: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-23K22613/) Japan Society for the Promotion of Science (JSPS) (URI: https://www.jsps.go.jp/english/), grant/award no. 22K18426: Linkage of the Earth's tipping points and the subseafloor biosphere (URI: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-22K18426/) Japan Society for the Promotion of Science (JSPS) (URI: https://www.jsps.go.jp/english/), grant/award no. 23H00153: Analysis of internal Earth nitrogen using pupulin nitrogen isotope ratio (URI: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-23H00153/) Japan Society for the Promotion of Science (JSPS) (URI: https://www.jsps.go.jp/english/), grant/award no. JPJSCCA20250004: Warm-period Climate Change Research Center with the International Ocean Drilling School [WarmCCR] (URI: https://sites.google.com/view/kochi-jsps-core2core/english?authuser=0) Parameter(s): Sample code/label (Sample label) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) SECTION, height [m] (Section) * GEOCODE * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * COMMENT: Stratigraphic levels are given in meters from the base of the Kawaruppu section, which is defined as 0 m. Main Lithology (Main lith) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) Sodium oxide [%] (Na2O) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Magnesium oxide [%] (MgO) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Aluminium oxide [%] (Al2O3) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Silicon dioxide [%] (SiO2) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Phosphorus pentoxide [%] (P2O5) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Potassium oxide [%] (K2O) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Calcium oxide [%] (CaO) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Titanium dioxide [%] (TiO2) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Chromium(III) oxide [%] (Cr2O3) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Manganese oxide [%] (MnO) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Iron oxide, Fe2O3 [%] (Fe2O3) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Nickel oxide [%] (NiO) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II * COMMENT: mass% Loss on ignition [%] (LOI) * PI: Ota, Hayu (https://orcid.org/0009-0001-7029-2067, h-ota@g.ecc.u-tokyo.ac.jp) * METHOD/DEVICE: X-ray fluorescence spectrometer (XRF), Rigaku Holdings Corporation, ZSX Primus II License: Creative Commons Attribution 4.0 International (CC-BY-4.0) (URI: https://creativecommons.org/licenses/by/4.0/) Status: Curation Level: Enhanced curation (URI: https://wiki.pangaea.de/wiki/Curation_levels) Size: 105 data points */ Sample label Section [m] Main lith Na2O [%] MgO [%] Al2O3 [%] SiO2 [%] P2O5 [%] K2O [%] CaO [%] TiO2 [%] Cr2O3 [%] MnO [%] Fe2O3 [%] NiO [%] LOI [%] KWR4-01 173.00 mudstone 2.693 2.198 16.954 65.207 0.159 3.051 0.743 0.741 0.020 0.042 6.575 0.004 3.592 KWR4-03 173.20 mudstone 2.542 2.206 16.744 65.340 0.154 3.170 0.712 0.728 0.020 0.044 6.877 0.004 3.699 KWR4-04 173.30 mudstone 2.434 2.273 18.076 63.926 0.160 3.501 0.886 0.734 0.019 0.042 6.606 0.004 4.038 KWR4-04'' 173.32 mudstone 2.405 2.249 17.704 63.675 0.154 3.416 0.898 0.707 0.020 0.041 6.873 0.005 4.152 KWR4-05 173.40 mudstone 2.514 2.189 17.014 64.904 0.154 3.231 0.758 0.760 0.021 0.038 6.673 0.004 3.827 KWR4-06 173.48 mudstone 2.539 2.207 17.129 64.972 0.157 3.269 0.741 0.762 0.023 0.040 6.623 0.004 3.769 KWR4-07 173.55 mudstone 2.774 2.194 17.303 64.429 0.162 3.211 0.747 0.767 0.021 0.041 6.705 0.003 3.800