Geomagnetic secular variations over the last 23 ka recorded in Lake Chala, eastern equatorial Africa

<p>Documenting the Earth&#8217;s magnetic field variations through time is fundamental for several disciplines. However, current geomagnetic models heavily rely on datasets biased towards mid- and high northern latitudes, whereas data from Africa and surrounding oceans are particularly underrepresented. In this study, we present a new record of paleo-secular variations (PSV) in geomagnetic field inclinations during the last 23 ka from Lake Chala, situated at 3&#176; S near Mt Kilimanjaro in eastern equatorial Africa. This deep groundwater-fed crater lake is characterized by a high sedimentation rate (<em>ca.</em> 1 cm/10 years) and a particularly well-constrained age model based on ²¹⁰Pb and ¹⁴C dating; and rock magnetic analyses have demonstrated the magnetic stability of the sediments. The Chala dataset is linked to PSV records from Lake Malawi and Lake Victoria using a sequence slotting technique to generate a composite PSV record for East Africa. The Lake Chala PSV record not only represents an important contribution toward a better understanding of local and global features of the Earth&#8217;s magnetic field, but also expands the utility of paleomagnetism as a key tool for dating of, and cross-correlation between, lake-based paleoenvironmental records and archeological sites throughout eastern tropical Africa.</p>