What is the relative movement of rocks on the west side of the San Andreas fault compared to the direction the North American Plate is moving

It I moving northwest while the north American plate is moving South east.

Explanation:

San Andreas fault is a continental fault that move through California.

San Andreas fault forms the tectonic boundary between the Pacific Plate and the North American Plate. Both plates move in the north Westerly direction but the Pacific plates move in northwest direction and American plate move in South East direction.

The Pacific plates move in North West direction because of the sea floor spreading from the East Pacific rise in the gulf of California.

The American plates move South East because of the sea floor spreading from the Mid Atlantic Ridge (divergent margin.