Select the statements about the K-T boundary that are true.
- The K-T boundary in Zumaia, Spain is sharp--representing an abrupt change in the marine ecosystem.
- The K-T boundary separates rock layers of the Cretaceous period from those of the Tertiary period.
- The K-T boundary dates to 65 million years ago (when the dinosaurs disappeared).
- The K-T boundary is a layer of debris ranging from large chunks of fractured rock to thin clay deposits and it is found in many different parts of the world. It separates rock layers from the end of the Cretaceous period from those beginning of the Tertiary period. It coincides with an abrupt loss of biodiversity.