The Javelina Formation is a geological formation in Texas. Dating has shown that the strata date to the mid-late Maastrichtian

Maastrichtian

The Maastrichtian is, in the ICS' geologic timescale, the latest age or upper stage of the Late Cretaceous epoch or Upper Cretaceous series, the Cretaceous period or system, and of the Mesozoic era or erathem. It spanned from 70.6 ± 0.6 Ma to 65.5 ± 0.3 Ma...

 stage of the Late Cretaceous

Late Cretaceous

The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...

, with the middle part of the formation dated to about 69 million years ago plus or minus 1 Ma and the top situated near the K-Pg boundary, dated to 65.5 Ma ago. Dinosaur remains are among the fossils that have been recovered from the formation.

Vertebrate paleofauna

• Alamosaurus sanjuanensis
• cf. Edmontosaurus
  Edmontosaurus
  Edmontosaurus is a genus of crestless hadrosaurid dinosaur. It contains two species: Edmontosaurus regalis and Edmontosaurus annectens. Fossils of E. regalis have been found in rocks of western North America that date from the late Campanian stage of the Cretaceous Period 73 million years ago,...
  
  sp.
• Quetzalcoatlus northropi
• cf. Torosaurus latus
• Torosaurus utahensis (Torosaurus latus)
• cf. Troodon
  Troodon
  Troodon is a genus of relatively small, bird-like dinosaur from the Late Cretaceous period . Discovered in 1855, it was among the first dinosaurs found in North America...
  
  sp.
• Tyrannosaurus rex