Nacimiento Formation Nacimiento Formation The Nacimiento Formation is a sedimentary rock formation found in the San Juan Basin of western New Mexico (United States) and named for the Nacimiento Mountains. It is a heterogeneous nonmarine formation composed of shale, siltstone, and sandstone, deposited in floodplain, fluvial and lacustrine settings, and made up of sediment shed from the San Juan uplift to the north and the Brazos-Sangre de Cristo uplift to the east. It was deposited mostly between ~64.5 and ~61 million years ago, during the early and middle Paleocene. The climate was humid and warm to hot. This unit interbeds with the
Acadia Cliffs State Nature Preserve The name derives from the fact that the land was formerly owned by the Acadia Coal Company. The property includes an old millstone quarry, and many old millstones can still be seen on the site, now back in the forest. This nature preserve was established in part to protect the Bradley's spleenwort, "Asplenium bradleyi", which grows there. The spleenwort is a state-listed plant species. Acadia Cliffs State Nature Preserve Acadia Cliffs State Nature Preserve is a state nature preserve in Washington County, Ohio, United States, with a small neck extending into Athens County, Ohio. Covering an area of , it