Abstract Historical documents, archives and old photographic collections allowed to analyze 877 direct geomagnetic measurement data obtained by sailors (including pirates), United States Coast and Geodetic Survey and National Astronomical Observatory since 1587. The updated catalogue includes 844 values of magnetic declination, 495 of inclination, 467 of the horizontal intensity component (H) and 455 of the vertical intensity component (Z). All data were relocated to Mexico City through the pole conversion method in order to build a reference secular variation curve for Mexico and surrounding area using bootstrap method to mitigate the effect of outliers and estimate the probability of density functions. The directional variation patterns obtained in this investigation were compared to the curves retrieved from Sha.Dif.14k, GUFM1and IGRF-12 models while VADM fluctuations were confronted to similar quality determinations from other localities worldwide as well as archaeomagnetic curves from Mesoamerica.

中文翻译：

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档案文件揭示了自 1587 年以来墨西哥地球磁场元素的波动

摘要 历史文件、档案和旧照片收藏允许分析自 1587 年以来由水手（包括海盗）、美国海岸和大地测量局和国家天文台获得的 877 个直接地磁测量数据。更新的目录包括 844 个磁偏角值，495 个倾斜度，水平强度分量 (H) 为 467，垂直强度分量 (Z) 为 455。所有数据通过极点转换方法重新定位到墨西哥城，以便使用引导法构建墨西哥及周边地区的参考长期变化曲线，以减轻异常值的影响并估计密度函数的概率。在本次调查中获得的方向变化模式与从 Sha.Dif.14k 中检索到的曲线进行了比较，