Scientists have discovered levels of iridium 30 times greater than average in the Cretaceous/Tertiary (KT) boundary, the layer of sedimentary rock laid down at the time of the dinosaur extinction.

For decades, the prevailing theory behind the mass extinction that ended the reign of the dinosaurs has pointed to a ...

The extinction of the dinosaurs has been a hotly debated ... Researchers have found plenty of stuff in the K-Pg layer, including iridium and chromium. Iridium is rare on Earth but common on ...

The dinosaurs were not in decline before the asteroid hit, a new study finds. Instead, poor fossilization conditions and ...

(CNN) --Scientists have long thought that a massive asteroid strike some 65 million years ago doomed the dinosaurs ... of an element called iridium in earth's sediment layers dating back about ...

Ruben, age 5, wants to know if dinosaurs still exist ... There, he found a thin layer of clay with an unusual amount of a metal called iridium in it. The clay was in between rocks from the ...

Some scientists think the presence of high concentrations of iridium at the geological layer associated with the dinosaur extinction could be the result of extremely large-scale volcanic activity.