San Nicolas Geology
San Nicolas is the outermost island in the California Channel
archipelago, and is a total of 22 square miles. It is most well known as the home of the Lone Woman of San Nicolas, the last Native American to reside on the island, and who was inadvertently left stranded there alone for eighteen years. Her life is the basis for Scott Odellís book and movie, Island of the Blue Dolphin.
San Nicolas appears to be the one Channel Island that is not directly
of volcanic origin as it does not have igneous rock. Its foundation is a sandstone bedrock that is layered by marine terraces. The highest point on the island is Jackson Hill at 907 feet, and the majority of the mountainless island is shifting sand dunes, with an estimated 75% of the island in motion as the dunes respond to wind and weather.
As with its neighbors to the north and south, San Nicolas has a caliche
forest, which is an other worldly appearing mineral formation that has adhered to the lifeless remains of low lying vegetation. The caliche formation are made of rhizoconcretions that form eerie, abstract landscapes of bizarre form. The materials that work together to form a caliche forest are calcium carbonate, sand, gravel, silt and clay.