Start:

Graptolites, lowest occurrences of Parakidograptus acuminatus and Akidograptus ascensus.

Index Fossils:

Trilobites, Graptolites, Coral and Nautiloid Cephalopod

Evolution:

Coral reefs; giant scorpions; first jawed fish

Geography:

Rising mountains, continent fragmenting resulting in six continents, deeper seas

Rocks:

limestone, dolomite and salts