Pete--- the rocks are near the San Andreas fault in California...:they are sedimentary layers that were first laid down in the ocean, then exposed and hardened, then folded as explained below.

"Shown above are exposed sedimentary layers that have been drastically deformed by movement on the San Andreas Fault. The location here is a freeway road-cut on SR-14, just north of the Avenue S off-ramp in Palmdale, California -- the camera is looking east. The San Andreas Fault is an approximately 700 mi (1,127 km) stretch of the boundary between the Pacific Plate and the North American Plate. It's a right lateral transform fault (one of the longest in the world) and has played an important role in the geologic, as well as the human history of California." Palmdale, California Coordinates: 34.562907, -118.132587

they are sedimentary layers that were first laid down in the ocean, then exposed and hardened, then folded .

They are similar to these:also in California...long explanation on the page. (rocks in the 2nd page are described as "sandstone, siltstone and limestone."