GEOLOGY

Detailed explanation-1: -San Andreas Fault Zone (SAFZ) started moving about 28-30 million years ago and has horizontally slipped (transform motion) a total of about 300-350 km (186-220 mi)since it began moving.

Detailed explanation-2: -The San Andreas Fault, stretching along the central west coast of North America, is one of the most active faults on the Ring of Fire. It lies on the transform boundary between the North American Plate, which is moving south, and the Pacific Plate, which is moving north.

Detailed explanation-3: -The Pacific Plate (on the west) slides horizontally northwestward relative to the North American Plate (on the east), causing earthquakes along the San Andreas and associated faults. The San Andreas fault is a transform plate boundary, accomodating horizontal relative motions.

Detailed explanation-4: -Near Alaska, the North American Plate meets the Pacific Plate in a convergent boundary, meaning the plates are coming together. Here, the Pacific Plate sinks under the North American Plate in a process called subduction.

Detailed explanation-5: -The Pacific Plate is moving to the northwest at a speed of between 7 and 11 centimeters (cm) or  3-4 inches a year. The North American plate is moving to the west-southwest at about 2.3 cm ( 1 inch) per year driven by the spreading center that created the Atlantic Ocean, the Mid Atlantic Ridge.