Also known as Loc. 19
Where: Baja California Sur, Mexico (26.2° N, 112.3° W: paleocoordinates 24.9° N, 103.9° W)
• coordinate based on nearby landmark
• outcrop-level geographic resolution
When: San Gregorio Formation, Chattian (28.1 - 23.0 Ma)
• The San Gregorio Formation lies unconformably below the upper Ysidro sandstone and appears to be no more than 400 ft thick. Because of its similarity to the Monterey Formation of California Darton (1921) tentatively correlated the beds and named them the "Monterey beds". Limited evidence points to an Oligocene age, although the formation is tentatively assigned an Oligocene to early Miocene age based on macrofossils and diatoms.
• bed-level stratigraphic resolution
Environment/lithology: marine; brown, argillaceous shale
Size class: macrofossils
Collection methods: quarrying,
• Collected by Darton (1921), studied and determined by J. Gardner. No known repository.
Primary reference: C. H. Beal. 1948. Reconnaissance of the geology and oil possibilities of Baja California, Mexico. Geological Society of America Memoir 31 [A. Miller/A. Hendy/A. Hendy]more details
Purpose of describing collection: biostratigraphic analysis
PaleoDB collection 43805: authorized by Austin Hendy, entered by Austin Hendy on 26.08.2004, edited by Mark Uhen
Creative Commons license: CC BY (attribution)