"Kala" and "Chitta" are Punjabi words, meaning "black" and "white", respectively.

[1][2][3] Pakistan's Kuldana Formation is best known for its fossil Eocene mammals, including primitive cetaceans such as Pakicetus, Ambulocetus and Attockicetus.

[4] The Kuldana Formation is located in the Kala Chita hills and is a thin, 20-120 m thick tongue of low-lying continental red beds that lie within a much thicker sequence of foraminifera-rich marine formations.

Shallow planktonic and benthic foraminifera limit the age of the Kuldana Formation to the late early or early middle Eocene, and the current interpretation of global sea level stratigraphy favours the latter.

[5] The Kohat formation consists of calcareous shale and light grey limestone.