1. Franciscan Complex: The Franciscan Complex is a group of rocks formed from the subduction of the Farallon Plate beneath the North American Plate. These rocks are highly deformed, fractured, and sheared. The Franciscan Complex in Redwood National Park consists primarily of sandstone, shale, greenstone, and chert.
2. Coastal Sedimentary Rocks: Along the coastline of Redwood National Park, sedimentary rocks such as sandstone and shale are found. These rocks were formed from the accumulation of sediments deposited by rivers and coastal currents over millions of years. They contain various fossils, including marine invertebrates and plants.
3. Granitic Rocks: Granitic rocks, including granite and granodiorite, are found within the park. These rocks were formed from the cooling and solidification of magma deep beneath the Earth's surface. Granitic rocks are resistant to erosion, resulting in the formation of domes, spires, and other prominent features.
4. Metamorphic Rocks: Some areas of Redwood National Park contain metamorphic rocks, such as schist and gneiss. These rocks were originally sedimentary or igneous rocks that underwent intense heat and pressure, causing their transformation into metamorphic rocks.
5. Quaternary Alluvial Deposits: Along river valleys and floodplains, Quaternary alluvial deposits are present. These deposits consist of gravel, sand, silt, and clay transported and deposited by rivers and streams over time.
The distribution and occurrence of these rock types within Redwood National Park provide insights into the region's geological history, including plate tectonics, sedimentary processes, and the influence of erosional forces over millions of years.
