What age range does the tertiary period of geologic time refer to?

The tertiary period of geologic time indeed refers to the time span that comes immediately before the Quaternary period. The Tertiary period itself is part of the Cenozoic era and encompasses a significant period in Earth's history, marked by the development and evolution of mammals and the rise of flowering plants.

To provide some context, the Tertiary is notable for its warm climates and various geological and biological changes that set the stage for the conditions we observe today. Understanding this sequence of geological time is crucial because it helps depict the progression of life forms and the Earth's climatic changes through eons, leading up to the Quaternary period, which we are currently in.