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Several magnetic measurements and theoretical development from different research groups have shown certain relationship with worldwide geological processes. Secular variation of geomagnetic cut off rigidity, magnetic frequencies, or magnetic anomalies have been linked with spatial properties of active convergent tectonic margin or earthquakes occurrences during recent years. These include the rise of similar fundamental frequencies in the range of micro hertz before Maule 2010, Japan 2011, and Sumatra 2004 earthquakes and the dramatic rise of the cumulative number of magnetic anomalous peaks before several earthquakes as Nepal 2015 and Mexico 2017, among others. Currently, all of these measurements have been physically explained by the microcrack generation due uniaxial stress change in rock experiments. The basic physics of these experiments have been used to describe the lithospheric behavior in the context of the seismo-electromagnetic theory. Due to the dramatic increase in experimental evidence, physical mechanism and theoretical framework, this paper analyses vertical magnetic behavior close to the latest three main earthquakes in Chile: Maule 2010 (Mw8.8), Iquique 2014 (Mw8.2), and Illapel 2015 (Mw8.3). The FFT, Wavelet transform and daily cumulative number of anomalies methods were used during quiet space weather time during one year before and after each earthquake in order to filter space influence. FFT Method confirm the raise of power spectral density in mHz range before one month each earthquake, which decrease to lower values after some months after earthquake occurrence. The cumulative anomalies method exhibited and increase previous to each Chilean earthquake (50-90 days prior earthquakes) similar to those found for Nepal 2015 and Mexico 2017. The wavelet analyses also show as similar properties as FFT analysis. However, the lack of physics-based constrain in the wavelet analysis do not allow conclusion as strong as FFT and cumulative methods. By using these results and previous research, it could be stated that these magnetic features could give seismic information from impending events. Additionally, these results could be related to the Lithosphere-Atmosphere-Ionosphere coupling (LAIC effect) and the growth of micro cracks and electrification in rocks described by the seismo-electromagnetic theory. [ABSTRACT FROM AUTHOR]