K-T and Caves

Today was our first day out in the field with Sandro. He walked us through the geology of the area and the rocks we would be seeing. We stopped at a special outcrop, one that contains the K-T boundary (now renamed K-Pg for Cretaceous–Paleogene). This was a huge mass extinction event that led to the end of the dinosaurs, as well as a lot of other species. This event is recorded in a small clay layer amidst the limestones--a layer which has a high Iridium content. Iridium is an element that, in excess of background levels, points to extraterrestrial impact: big meteor, big crash, fire, brimstone, tsunamis, dino death, and the rise of the mammals, so us!

The K-Pg boundary is the dark bedding plane below Sandro's hand.

In the evening, Sandro took us inside the Grotte di Frasassi (Frasassi Caves), some of the most famous show caves in Italy. It is in these caves that Sandro studies uplift rates based on the features, such as stalagmites and stalactites. The biggest cavern was nearly 800ft high, though it is hard to fully grasp the immensity because of the lack of light. All in all, it was quite an experience.

You can see the ridge that contains the Frasassi caves. The river has cut through the ridge due to uplift.

The stalagmites and stalactites of the Frasassi caves.