magnetoestratigrafías

Magnetoestratigrafías is a dating method used in geology and paleontology that utilizes the Earth's magnetic field reversals recorded in rocks. The Earth's magnetic field has periodically reversed its polarity throughout geological history, meaning the North magnetic pole has switched places with the South magnetic pole. These reversals are recorded as permanent magnetic signatures within igneous and sedimentary rocks as they form.

The study of these magnetic signatures is called paleomagnetism. When rocks cool from a molten state or when sediments are deposited, magnetic minerals within them align with the Earth's prevailing magnetic field at that time. This alignment is preserved as the rock solidifies or compacts. By analyzing the direction and intensity of the remnant magnetism in rock samples, geologists can determine the orientation of the Earth's magnetic field when the rock was formed.

Magnetoestratigrafías involves correlating patterns of magnetic reversals observed in a rock sequence with a globally established timescale of these reversals, known as the Geomagnetic Polarity Timescale (GPTS). This timescale has been built over decades by studying rocks of known absolute ages from various locations worldwide. By matching the observed polarity sequence in a particular stratigraphic section to the GPTS, geologists can assign ages to the rock layers, even in the absence of other fossil or radiometric dating evidence. This technique is particularly valuable for dating sedimentary sequences where other methods may be limited.