Lava Beds National Monument Stronghold, which is 450,000 years old. Petroglyph Point was created about 275,000 years ago when cinders erupted through the shallow water of Tule Lake; violent explosions of ash and steam formed layers upon layers of tuff. The caldera is thought to have formed by subsidence, during which basalt and andesite were erupted up on the slopes. Lava flows dated to about 30,000–40,000 years ago formed most of the lava tube caves in the monument. As the hot basaltic lava flowed downhill, the top cooled and crusted over, insulating the rest of the lava and forming lava tubes. Lavacicles on the
Lava Cast Forest 1942, the United States Forest Service designated 5,120 acres as part of the Lava Cast Forest Geological Area and were promoted as a tourist attraction. In 1963, scientists from NASA became interested in the lava fields because they had very little erosion and they suspected it might be what they would find on the surface of the Moon. From 1964 to 1966, at least 46 astronauts trained for lunar missions in the area. James B. Irwin delivered a rock from one of Oregon's lava flows to the lunar surface to commemorate NASA's experiences in central Oregon. Lava Cast Forest Lava