[1] The middle part of the formation has been dated to about 69 million years ago plus or minus 1 million years and the top situated near the Cretaceous–Paleogene boundary (in the overlying Black Peaks Formation[1]), dated to 66 Ma ago.

[3] The typical age range of the Javelina Formation has been difficult to determine.

[4] Only one geological site in the Javelina Formation has thus far yielded the correct rock types for radiometric dating.

The outcrop, situated in the middle strata of the formation about 90 meters below the K-Pg boundary and within the local range of Alamosaurus fossils and below two sites that have yielded Quetzalcoatlus fossils, was dated to 69.0 plus or minus 0.9 million years old in 2010.

[5] Woody dicots and angiosperms have been unearthed in this formation.