obelisk, and a visitors' log. Climate Black Mesa is not only the highest point in Oklahoma but it is also the driest, harshest and coldest place in the state. A nearby weather station is located in Kenton. Geology The visual and map view appearance of Black Mesa is as an "inverted valley" because erosion has removed the relatively soft sedimentary strata from either side of the resistant Raton basalt of the lava which originally had occupied and filled a river valley. The mesa is capped by erosion-resistant basaltic lava formed by a volcanic eruption 3 to 5 million years ago. The lava erupted from a vent in the Raton-Clayton volcanic field in northeastern New Mexico and southeastern Colorado. The volcanic cap to the mesa is thick, long and from 0.5 miles to 8 miles wide, which is to the north-northwest of Oklahoma. The erupting lava filled a stream channel in the Pliocene age Ogallala Formation. During the years since the eruption, the adjacent rock of the Ogallala and older formations have been removed leaving the valley-filling basalt perched atop a long ridge. Strata exposed along the mesa below the basalt and Ogallala include the Cretaceous Dakota Sandstone and the Jurassic Morrison Formation. Beginning in 1935, geologists and paleontologists have searched the mesa's outcroppings, finding dinosaur fossils in the Jurassic and Triassic strata. A large quantity of dinosaur bones has been recovered from the Black Mesa locale; totaling over eighteen tonnes. These remains were split between several species, including stegosaurus, camptosaurus, diplodocus, and edmontosaurus. Clear fossil physical evidence, a distinct line of footprints believed to have been made by an allosaurus, has been found juxtaposed with the Carrizo Creek, which runs around the modern-day northern edge of the mesa. Protected area The mesa lies in the protected area known as the Black Mesa Nature Preserve which was established in 1991, covering . The preserve protects 60% of the area of the mesa peak. The peak is accessible along an trail. Apart from the nature reserve, there is also the Black Mesa State Park encompassing , with a lake known as Lake Carl Etling. The park is a recreational area with many facilities for camping, hiking and many other outdoor activities. The park is about 15 miles away from the peak. Wildlife The flora and fauna and terrain of Black Mesa are unique in Oklahoma, more typical of the semi-arid grasslands and