What might you find in marine sediments that would be somewhat unique compared to other us locations?

In marine sediments near the coast of California, for example, one might find small, round balls of tar, also called "fossil fuel seeps" or "tar balls." These tar balls are formed when crude oil from natural seeps on the seafloor rises to the surface and reacts with the air, forming a tarry substance. These tar balls can then sink to the bottom and become incorporated into the marine sediments. Over time, these tar balls can become buried under layers of sediment and be preserved for millions of years. They are a unique feature of marine sediments in certain coastal areas.