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
Waitabit Cliffs Waitabit Cliffs Waitabit Cliffs () is a line of sedimentary cliffs on the east coast of Alexander Island, Antarctica, which faces east onto George VI Sound and extends 3 nautical miles (6 km) north from the mouth of Mercury Glacier. The cliffs were probably first sighted by Lincoln Ellsworth, who flew directly over it and photographed segments of this coast on November 23, 1935. First roughly surveyed in 1936 by the British Graham Land Expedition. Resurveyed in 1949 by the Falkland Islands Dependencies Survey, at which time the rock strata were independently examined by members of the party at two