The Hall Lake Formation, formerly called the Hall Lake Member, is a geological formation in Sierra County, New Mexico preserving Lancian fauna, most notably dinosaurs.

It is regarded as a member of the McRae Group, including the Elephant Butte and Staton-LaPoint locales.

[2] While most estimates place it firmly within the Lancian fauna, specifically using taxa such as Compsemys as index fossils to recover a Campanian-Maastrichtian age,[3] Lozinsky et al. (1984) note the presence of basalt flows and alluvium dating to the Quaternary-Tertiary.

It overlooks the Jose Creek Member and is composed of purple and maroon shales.

Various Cenozoic units overly the formation.