While some believe the ziggurat-like formation is from an ancient city, others argue that it was naturally created.
The image of the police formation was from Wednesday, not Tuesday, and the photo was taken by Mario Anzuoni, not Whitney Curtis.
Moreover, if the formation is from the later parts of the Early Permian, it is roughly the age when we would expect early therapsids to be present.
It is a metamorphic product of limestone (a carbonate rock), whose dominant mode of formation is from various organisms living in water.
The formation is from the Early Cretaceous, and dates from 145.5 to 136.4 million years ago.
The upper region of the Aguja Formation is from the Kirtlandian.
The age of Prosaurolophus maximus remains from this formation is from approximately 71.5 to 71.0 million years ago.
1,2-Diphytanoyl sn-glycero-3-phosphocholine used for lipid bilayer formation was from Avanti Polar Lipids (Alabaster, AL, USA) and used without further purification.
The stratigraphic formations are (from the oldest to the youngest): the Middle Triassic Muschelkalk subdivided into Lower Muschelkalk (Wellenkalk), Middle Muschelkalk, and Upper Muschelkalk (Hauptmuschelkalk), and the Upper Triassic Keuper which is subdivided into Lower Keuper (Lettenkeuper), Middle Keuper (Gipskeuper), and Upper Keuper.
San Rafael Group formations are (from oldest to youngest); Page Sandstone, Carmel Formation, Entrada Sandstone, Curtis Formation, and Summerville Formation.
