Beneath the vegetation blanketing much of Channel Islands National Park are many layers of earth and rock. At first glance these land-based physical resources are little more than the foundation of a captivating landscape. Upon closer inspection, however, they start to reveal their secrets.
A huge diversity of geologic formations, from pillow lava and lava “bombs” to sedimentary rock layers, marine terraces, and chert deposits, all help tell the story of the Channel Islands’ past dating back more than 100 million years. It is an often dramatic tale of colliding plates, misaligned magnetic particles, volcanic activity, and not-so-subtle changes in climate and sea level.
The various soils found in Channel Islands National Park have their own stories to share, largely by way of erosion patterns. Erosion can shed light on natural processes like wind, rain and earthquakes, as well as on the effects that humans have had on the landscape. The introduction of domestic animals to the Channel Islands, for instance, resulted in the over-consumption of the islands’ vegetation, leaving the soil below exposed to the elements in many areas. This in turn led to severe erosion and other changes in soil quality across the islands.