Geology of the Rocky Mountains Japan, Indonesia and the Aleutians; others are fragments of oceanic crust obducted onto the continental margin while others represent small isolated mid-oceanic islands. Magma generated above the subducting slab rose into the North American continental crust about inland. Great arc-shaped volcanic mountain ranges, known as the Sierran Arc, grew as lava and ash spewed out of dozens of individual volcanoes. Beneath the surface, great masses of molten rock were injected and hardened in place. For 270 million years, the effects of plate collisions were focused very near the edge of the North American plate boundary, far to the west of
The Powers of the Earth The Powers of the Earth The Powers of the Earth is a 2017 libertarian hard science fiction novel by Travis J I Corcoran. It is his debut novel, and the first release in the Aristillus Series. An ungoverned lunar settlement whose economy developed while Earth's economy declined under a command-and-control economy engages in a struggle stay free from Earth's meddling bureaucracy. The lunar colonists engage in military conflicts with the Earth forces on the surface of the moon, in space ships flying between Earth and the moon, and in the tunnels of the city of Aristillus. The novel deals with