Besides the direct effect of asteroid impacts on a planet's surface topography, global climate and life, recent studies have shown that several consecutive impacts might have an effect on the dynamo mechanism at a planet's core responsible for maintaining the magnetic field of the planet, and may have contributed to Mars' lack of current magnetic field. An impact event may cause a mantle plume (volcanism) at the antipodal point of the impact. The Chicxulub impact may have increased volcanism at mid-ocean ridges and has been proposed to have triggered flood basalt volcanism at the Deccan Traps.