Wheel and axle. The wheel and axle is one of six simple machines identified by Renaissance scientists drawing from Greek texts on technology. The wheel and axle consists of a wheel attached to a smaller axle so that these two parts rotate together in which a force is transferred from one to the other.
The San Andreas Fault is the sliding boundary between the Pacific Plate and the North American Plate. It slices California in two from Cape Mendocino to the Mexican border. San Diego, Los Angeles and Big Sur are on the Pacific Plate. San Francisco, Sacramento and the Sierra Nevada are on the North American Plate. And despite San Franciscoâs legendary 1906 earthquake, the San Andreas Fault does not go through the city.
Blocks on opposite sides of the San Andreas fault move horizontally. If a person stood on one side of the fault and looked across it, the block on the opposite side would appear to have moved to the right. Geologists refer to this type fault displacement as right-lateral strike-slip.