The Fenambosy Chevron is one of four chevron-shaped land features on the southwest coast of Madagascar, near the tip of Madagascar, 180 metres high and 5 km inland. It is composed mainly of material found on the ocean. Chevrons such as Fenambosy have been hypothesized as providing evidence of "megatsunamis" caused by comets or asteroids crashing into Earth. About 900 miles southeast from the Madagascar chevrons, in deep ocean, is Burckle crater, which Dallas Abbott discovered in 2005.[1] Although its sediments have not been directly sampled, cores from the area contain high levels of nickel and magnetic components associated with impact ejecta. Burckle crater has not been dated, but Abbott estimates that it is 4,500 to 5,000 years old.