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North Pacific Ocean sediments are important archives of geomagnetic field and paleoenvironmental evolutions, yet late Quaternary sedimentary sequences in the North Pacific Ocean are less explored because of generally low sedimentation rates and the challenge of dating sediments deposited below the calcite compensation depth. Core NP02 sediments from the North Pacific Ocean contain three visible tephra layers, which are identified as the To‐Of, Spfa‐1, and Kt‐3 tephra, respectively. An age model for core NP02 is established based on tephra correlation and one radiocarbon date, which gives a mean sedimentation rate of ∼11.6 cm/kyr. Magnetic analyses suggest the dominance of two remanence carriers; detrital vortex state and biogenic single domain magnetite. Variable depth offsets between the relative paleointensity (RPI) signals carried by the two remanence carriers adds a negligible age error (<0.5 kyr) to the core NP02 RPI record. Pronounced RPI amplitude variations are observed, and the Rockall and Laschamp excursions are identified in the core NP02 RPI record based on the age model. The fidelity of the core NP02 RPI record is further verified by comparison with other RPI stacks and records, and we demonstrate that the RPI variations can assist in chronology refinement. Plain Language Summary: The North Pacific Ocean is too deep to preserve materials effectively for the oxygen isotope chronology, and sediments deposit slowly in this region. Therefore, dating is a big problem for late Quaternary sedimentary cores. In this study, core NP02 sediments from the North Pacific Ocean are studied. The To‐Of, Spfa‐1, and Kt‐3 tephra layers are identified in core NP02 sediments based on the geochemical features. An age model for this core is reconstructed with the aid of tephra ages and one radiocarbon date. Magnetic analyses suggest that both small biogenic and relatively large detrital magnetite record geomagnetic information, and the two groups of magnetite deposit at about the same time. Based on the age model, core NP02 RPI record preserves the Rockall and Laschamp excursions, and the RPI pattern is consistent with other RPI stacks and records, which verifies core NP02 RPI fidelity. Therefore, we demonstrate that RPI variations is a promising dating tool for North Pacific Ocean sediments. Key Points: We use an age model based on tephra correlation and one radiocarbon date to assess the fidelity of relative paleointensity variationsDetrital vortex state and biogenic single domain magnetite are the dominant remanence carriers, and they introduced <0.5 kyr age errorAssessment of component‐specific magnetic properties should be considered to ensure the reliability of relative paleointensity variations [ABSTRACT FROM AUTHOR]

Abstract: Prehistoric Holocene eruptions of Changbaishan volcano in Northeast China are poorly dated, with the exception of the 946 CE Millennium eruption. Poorly refined age estimates for the earlier eruptions present problems for the reconstruction of the eruptive history of the volcano. The Qixiangzhan eruption (QE) is a major controversial event in terms of its eruptive timing (ranging from ~88 to ~4 kyr) and style (effusive or explosive). As a result of the imprecise age estimates for the eruption, a geomagnetic field excursion recorded within the QE comendite has been variably correlated with a number of different excursion events observed elsewhere. In this study, a visible early Holocene tephra was identified in Yuanchi Lake, ~30 km east of the Changbaishan volcanic vent, and was dated to 8831‐8100 cal yr BP using Bayesian age modelling. Glass shard compositions enable the correlation of this tephra with the poorly dated QE, as well as with a tephra (SG14‐1058) recorded in Lake Suigetsu, in central Japan. These correlations confirm that the QE was explosive and that the ash from the QE can serve as an important early Holocene marker bed across East Asia. In addition, we propose an age of ~8100 cal yr BP for the QE based on the precise date of the Suigetsu SG14‐1058 tephra. Our results also confirm that the geomagnetic field excursion recorded in the Qixiangzhan comendite dates to ~8100 cal yr BP. [ABSTRACT FROM AUTHOR]