Did the Chicxulub  Asteroid have a Companion? 

Soon after I noticed THIS ARTICLE on the BBC website, several people also mentioned it. It tells us about the discovery, off the west coast of North Africa, of a meteor crater which has an age similar to that at Chicxulub - the one that killed off the dinosaurs! (allegedly). You can read more about the discovery HERE. Both stories are based on THIS ACADEMIC PAPER.

The techniques used to find the crater are far from simple but we end up with a simple story. A smaller asteroid hit the Earth about the same time (geologically speaking) as the asteroid which marked the demise of the dinosaurs and other creatures. Was there a connection? - We do not know. 

The three papers discuss the possibilities in ever increasing detail but we may never have a definitive answer. But we do have a nice story.

Seismic characteristics of the Nadir Crater.

(A) Seabed depth map of crater showing seismic line locations and the mapped extent of the crater rim and damage zone. (B) W-E seismic section (pre-stack depth migration – depth domain) across the crater, highlighting the crater morphology and damage zone, and the extent of subsurface deformation. Data courtesy of the Republic of Guinea, TGS and WesternGeco. Stratigraphic key is on Fig. 1. (C) Detailed seismic stratigraphic and structural elements of the crater. KP, Cretaceous-Paleogene sequence (KP1 equivalent to Top Maastrichtian); KU, Upper Cretaceous seismic horizons. KU1 and KP1 “regionals” are schematic reconstructions of these seismic horizons before formation of the crater at the end of the Cretaceous and are used to reconstruct a conceptual model of crater formation (Fig. 5). (D) SW-NE seismic section (pre-stack time migration – time domain) across the crater, showing crater morphology and seismic facies outside the crater, including high-amplitude seismic facies sitting above a ~100-ms-thick unit of chaotic reflections, interpreted to have formed as a result of seismic shaking following the impact event. Data courtesy of the Republic of Guinea and WesternGeco Multiclient.