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The Cretaceous Normal Superchron (CNS, 84–121 Ma) is a singular period of the geodynamo's history, identified by a prolonged absence of polarity reversals. To better characterize the paleosecular variation (PSV) of the geomagnetic field at the end of this interval, we sampled seven continuous sequences of lava flows from the Okhotsk‐Chukotka Volcanic Belt, emplaced 84–89 Ma in the vicinity of the Kupol ore deposit (NE Russia). From a collection of 1,024 paleomagnetic cores out of 82 investigated lava flows, we successfully determined the paleodirections of 78 lava flows, which led to 57 directional groups after removing the serial correlations. The resulting paleomagnetic pole is located at 170.0°E, 76.8°N (A95 = 5.2°, N = 57), in good agreement with previous estimates for north‐eastern Eurasia. Aiming at quantifying PSV at a reconstructed paleolatitude (λ) of ∼80°N, we obtained a virtual geomagnetic pole (VGP) scatter Sb=21.5°|19.3°24.0°(N=57) ${{S}_{\mathrm{b}}=21.5{}^{\circ}\vert }_{19.3{}^{\circ}}^{24.0{}^{\circ}}\,(N=57)$, the value of which was corrected for within‐site dispersion and is little dependent on the choice of the selection criteria. Compared to previous paleodirectional data sets characterizing PSV at various paleolatitudes during the CNS, our Sb estimate confirms a relative latitudinal increase Sb(λ = 90°)/Sb(λ = 0°) on the order of 2–2.5. Focusing on PSV at high paleolatitude within the 70°–90° range, we show that Sb was ∼15% lower at the end of the CNS than during the past 10 Myr, confirming that the singular polarity regime of the geodynamo observed during the CNS is likely accompanied with reduced PSV. Plain Language Summary: Compared to the last 10 million years during which Earth's magnetic field stochastically reversed its polarity ∼4 times per million year, the Cretaceous Normal Superchron (CNS, 84–121 Ma) represents an anomalously long period of stable polarity, the understanding of which is crucial to constrain the working of the geodynamo. In this effort to better characterize the paleosecular variation (PSV) of the geodynamo, we investigated the paleomagnetic record of lava flow sequences from the Okhotsk‐Chukotka Volcanic Belt (NE Russia) emplaced 84–89 Ma at high paleolatitude. First, we obtained that the dispersion of virtual paleomagnetic poles (VGP), used as a proxy for PSV, is 2–2.5 times as high at the paleopole as at the paleoequator. Second, we showed that VGP scatter at high paleolatitude was ∼15% lower at the end of the CNS than during the last 10 million years, confirming a potential link between polarity regime and PSV. Key Points: We investigate geomagnetic field behavior at high paleolatitude (∼80°N) at the end of the Cretaceous Normal Superchron (CNS)We present a paleodirectional data set from 78 lava flows (resp. 57 directional groups), emplaced 84–89 Ma in north‐eastern EurasiaWe show that the dispersion of virtual geomagnetic poles at high latitude is ∼15% lower during the CNS than for the past 10 Myr [ABSTRACT FROM AUTHOR]

We conducted an absolute paleointensity survey on 74 lava flows from the Okhotsk–Chukotka Volcanic Belt (NE Russia), emplaced 90–83 Ma toward the end of the Cretaceous Normal Superchron (CNS, 121–84 Ma). Relying on preliminary results, we restricted our analysis to eight lava flows (140 Thellier–Coe experiments), two of which also yielded successful Wilson determinations. A detailed analysis of the magneto‐mineralogy—based on X‐ray structural analysis, reflected‐light microscopy, and thermomagnetic curves—indicates that the determinations from solely two lava flows can be fully trusted, with remanence carriers (a) dominated by low‐titanium titanomagnetite, (b) showing unambiguous traces of high‐temperature oxidation, and (c) yielding partial thermoremanent magnetization (pTRM) tails representative of pseudo‐single‐domain grains. Recalculated in terms of geomagnetic dipole strength, our two successful flow‐mean determinations yield virtual dipole moments of 4.76 ± 0.26 × 1022 Am2 (N = 7) and 9.07 ± 0.84 × 1022 Am2 (N = 8). Using an updated version of the paleointensity database for the Cretaceous epoch, we stress that determinations based on nonglassy whole rocks, submarine basaltic glasses, and single crystals are mutually inconsistent, suggesting a separate analysis of their distributions is more appropriate. Despite statistically indistinguishable estimates of dipole strength before and after the onset of the CNS—in accord with recent studies refuting the existence of a strict correlation between chron duration and dipole moment—we found that the distribution of dipole moments during the CNS is slightly bimodal with a leptokurtic dominant mode, thus more inclined to produce outliers and suggesting distinct geomagnetic field behavior during the CNS. Plain Language Summary: The Cretaceous Normal Superchron (CNS, 121–84 Ma) is a salient feature of the geomagnetic field during the Phanerozoic, characterized by an anomalously long period of stable polarity whereas Earth's magnetic field stochastically reversed its polarity approximately 4 times per Myr during the last 5 million years. Deciphering the geomagnetic behavior during the CNS, in terms of average dipole strength and variability, is thus essential to better understand the modus operandi of the geodynamo and better constrain numerical models. To this end, we conducted absolute paleointensity (API) experiments on lava flows from the Okhotsk–Chukotka Volcanic Belt (NE Russia), yielding two estimates of the geomagnetic dipole strength toward the end of the CNS. Using an updated version of the API database, we show that average dipole strength is statistically indistinguishable before and after the onset of the CNS, suggesting the absence of a strict correlation between duration of polarity intervals and average dipole strength. In contrast, we also show that the distribution of dipole strength estimates is slightly bimodal, with the dominant mode being more peaked than a normal distribution. This feature may point to a higher propensity of the geodynamo to produce outliers and thus distinct geomagnetic behavior during the CNS. Key Points: We investigate geomagnetic field behavior during the Cretaceous Normal Superchron (CNS), a ∼40 Myr interval of stable polarityWe present new absolute paleointensity data from Chukotka (NE Russia) emplaced at high latitude toward the end of the CNS (∼87 Ma)We show that geomagnetic dipole strength during the CNS may be bimodal, yet with a similar average than during the whole Cretaceous epoch [ABSTRACT FROM AUTHOR]