Geological history of Point Lobos
| Point Lobos State Reserve | |
|---|---|
 |
|
| Location |
Point Lobos, Monterey County, California |
| Nearest city | Carmel-by-the-Sea |
| Coordinates | 36°31′1.56″N 121°56′33.36″W / 36.5171000°N 121.9426000°WCoordinates: 36°31′1.56″N 121°56′33.36″W / 36.5171000°N 121.9426000°W |
| Governing body | California Department of Parks and Recreation |
The geological history of Point Lobos, regarding the Point Lobos headland on the Central Coast in Monterey County, California|Monterey County]], California.
The area's geology encompasses the last 80 million years. The oldest rocks exposed here were formed during the Cretaceous Period of the Mesozoic Era, when the dinosaurs still roamed the earth and pterodactyls dominated the sky. The area forms part of the Salinian Block, a sliver of continental crust caught up in the transform boundary between the Pacific and North American Plates.
Point Lobos is the common name for the landform and area, which include Point Lobos State Reserve on land; and two adjoining marine protected areas: Point Lobos State Marine Reserve (SMR) and Point Lobos State Marine Conservation Area.
During the Cretaceous period the west coast of North America was the site of an active chain of volcanoes. Active subduction created magma chambers that fed the volcanoes. This magma cooled slowly at depths of 10–20 km below the earth's surface to form a granitic intrusion known as the Santa Lucia Granodiorite. Granodiorite is made of quartz, orthoclase, plagioclase, amphibole, and biotite mica. Radiometric data indicate and age of 79.5 million years for the granodiorite. Over the next 30 million years the Santa Lucia Granodiorite rose to the earth's surface and was eroded. The granodiorite provides the basement rock for the younger sedimentary deposits of Point Lobos.
...
Wikipedia