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.

layer—the geologic boundary zone that seems to cap any known rock layers containing dinosaur fossils. Iridium is relatively rare in Earth's crust but is more abundant in stony meteorites ...

Hammond’s fascination and desire to revive dinosaurs backfires when many ... scientists developed this idea due to high amounts of iridium in the K-Pg layer of the geological boundary zone ...

The rock and sediment there had a similar composition to the iridium layers ... the early Jurassic, … the dinosaurs really took off.” Deeper in time, a mass extinction event that ended ...

The extinction of the dinosaurs has been a hotly debated ... Researchers have found plenty of stuff in the K-Pg layer, ...

The aftereffects of the collision resulted in the extinction ... death of the dinosaurs. Back then, the researchers didn’t find the asteroid itself; instead, they found a thin layer of the ...

Hammond's fascination and desire to revive dinosaurs backfires when many ... scientists developed this idea due to high amounts of iridium in the K-Pg layer of the geological boundary zone where ...