The 6.8-magnitude earthquake in Morocco, that has killed over 2,800 people, resulted from a geological phenomenon called a 'reverse fault', according to geologist Jesús Galindo-Zaldivar. The phenomenon occurs when tectonic plates collide, causing the Earth's crust to thicken. The stress along the fault lines can induce earthquakes as rocks abruptly shift to release accumulated stress, Jesús added.