Giant's Causeway cases the horizontal fracture has resulted in a bottom face that is convex while the upper face of the lower segment is concave, producing what are called "ball and socket" joints. The size of the columns is primarily determined by the speed at which lava from a volcanic eruption cools. The extensive fracture network produced the distinctive columns seen today. The basalts were originally part of a great volcanic plateau called the Thulean Plateau which formed during the Paleocene. According to legend, the columns are the remains of a causeway built by a giant. The story goes that the Irish
Natural Trap Cave become an experiment in taphonomy, in that its body has been allowed to lie undisturbed so as to study natural patterns and rates of decay. Natural Trap Cave Natural Trap Cave is a pit cave in the Bighorn Mountains, in northern Wyoming, United States. Excavations in the cave are an important source of paleontological information on the North American Late Pleistocene, due to a rich layer of fossils from animals that became trapped in the cave. The cave is located northeast of Lovell, Wyoming, at an elevation of . It is a bell-shaped pit or sinkhole within the Madison Limestone,