Constraining the long‐term variability and average of the Earth's magnetic field strength is fundamental to understanding the characteristics and behavior of the geomagnetic field. Questions remain about the strength of the average field, and the relationship between strength and reversal frequency, due to the dispersion of data from key time intervals. Here, we focus on the Cretaceous Normal Superchron (CNS; 121‐84 Ma), during which there were no reversals. We present new intensity results from 41 submarine basaltic glass (SBG) sites collected on the Nicoya Peninsula and Murcièlago Islands, Costa Rica. New and revised ⁴⁰Ar/³⁹Ar and biostratigraphic age constraints from previous studies indicate ages from 141 to 65 Ma. One site with an age of 135.1 ± 1.5 Ma (2σ) gave a reliable intensity result of 34 ± 8 µT (equivalent to a virtual axial dipole moment, VADM, value of 88 ± 20 ZAm²), three sites from 121 to 112 Ma, spanning the onset of the CNS, vary from 21 ± 1 to 34 ± 4 µT (53 ± 3 to 87 ± 10 ZAm²). These results from the CNS are all higher than the long‐term average of ∼42 ZAm² and data from Suhongtu, Mongolia (46–53 ZAm²) and are similar to the Troodos Ophiolite, Cyprus (81 ZAm², reinterpreted in this study). Together with the reinterpreted data, the new Costa Rica results suggest that the strength of the geomagnetic field was approximately the same both before and after the onset of the CNS. Therefore, the data do not support a strict correlation between polarity interval length and the strength of the magnetic field.

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地球磁场强度与白垩纪正常超时：哥斯达黎加的新数据

限制地球磁场强度的长期变化和平均值是理解地磁场的特征和行为的基础。由于关键时间间隔的数据分散，平均场的强度以及强度与反转频率之间的关系仍然存在问题。在这里，我们关注于白垩纪正时超同步（CNS； 121-84 Ma），在此期间没有逆转。我们提供了从尼科亚半岛和哥斯达黎加穆尔西拉戈群岛上收集的41个海底玄武玻璃（SBG）站点获得的新强度结果。新的和修订的⁴⁰ Ar / ³⁹先前研究的Ar和生物地层年龄限制表明年龄在141至65 Ma之间。年龄为135.1±1.5 Ma（2σ）的一个位置给出了可靠的强度结果34±8 µT（相当于虚拟轴向偶极矩VADM，值为88±20 ZAm ²），三个位置为121至112 Ma跨越CNS的发作时间，范围从21±1到34±4 µT（53±3到87±10 ZAm ²）。CNS的这些结果均高于〜42 ZAm ²的长期平均值和蒙古苏洪图（46-53 ZAm ²）的数据，与塞浦路斯Troodos蛇绿岩（81 ZAm ²）相似。，在本研究中进行了重新解释）。连同重新解释的数据，哥斯达黎加的新结果表明，中枢神经系统发作前后地磁场强度大致相同。因此，数据不支持极性间隔长度和磁场强度之间的严格相关性。