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°W / 36.5171000; -121.9426000
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.

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.^[1]

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.

Santa Lucia Granodiorite

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 an age of 79.5 million years for the granodiorite.^[2] 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.

Carmelo Formation

Around 55 million years ago, in the Paleocene Epoch of the Paleogene Period (Cenozoic Era), a submarine canyon cut down through the granodiorite basement rock and sediments comprising the Carmelo Formation were deposited. The Carmelo consists of pebble to cobble conglomerate, medium to coarse grained sandstone and mudstone. The included pebbles are mostly of volcanic origin. They were brought by rivers draining volcanic highlands. During transport their rough shape became rounded and polished. The sediments were deposited as submarine landslides and turbidity currents.^[3]

Fossils include shells, burrows that were made up by worms, and mysterious seaweed-like trace fossils. The shells, pebbles, and other material were deposited, together with sand and mud, within the walls of submarine canyons and became lithified. The Carmelo Formation is the second major rock type at Point Lobos. The Carmelo is easily recognizable along the southern shore of Point Lobos.^[4]^[5]

Marine terraces

About 18,000 years ago, during the Pleistocene Epoch of the Quaternary Period (Cenozoic Era), the level of the Pacific Ocean was considerably lower than it is now (because more water was in the polar ice-caps and continental glaciers). Deep submarine canyons were cut in the Monterey Bay area, as an extension of the Salinas River.

During late Cenozoic Era, because of sustained transpression of the Pacific Plate onto the American Plate along the nearby San Andreas Fault Zone, there was continued uplift of the entire coastline of California, so that erosive action of marine waves cut these terraces in the Monterey Bay area. Those Pleistocene marine terraces are composed of clay, silt, sand and gravel with a basal unconformity of gravel on top of rock. The creation of uplifted marine terraces that started to appear during the Pleistocene Epoch continues throughout the (present) Holocene Epoch of the Quaternary Period due to transpression of the Pacific Plate onto the American Plate. During the October 1989 Loma Prieta earthquake, the marine terraces of the Monterey Bay were further uplifted. Both Monterey and Santa Cruz have classical uplifted wave-cut shorelines with multiple sets of uplifted and exposed marine terraces.^[4]

Sand and gravel

The fourth and the youngest type of rocks is sand and gravel. It is found along the beaches. Once again it has been created by the action of waves and rain that cause erosion of the others type of rocks. The age of this kind of rocks varies from ten thousand years ago up to the present day.^[4]

References

External links

Protected areas of California

National Park System

National Parks	Channel Islands Death Valley Joshua Tree Kings Canyon Lassen Volcanic Pinnacles Redwood Sequoia Yosemite
National Preserves	Mojave
National Monuments	Cabrillo Castle Mountains César E. Chávez Devils Postpile Lava Beds Muir Woods Tule Lake
National Seashores	Point Reyes
National Historical Parks	Rosie the Riveter World War II Home Front San Francisco Maritime
National Historic Sites	Eugene O'Neill Fort Point John Muir Manzanar
National Memorials	Port Chicago Naval Magazine
National Recreation Areas	Golden Gate Santa Monica Mountains Whiskeytown–Shasta–Trinity

State Parks

State Parks	Ahjumawi Lava Springs Andrew Molera Angel Island Año Nuevo Anza-Borrego Desert Arthur B. Ripley Desert Woodland Bidwell–Sacramento River Big Basin Redwoods Border Field Bothe-Napa Valley Burton Creek Butano Calaveras Big Trees Castle Crags Castle Rock Caswell Memorial China Camp Chino Hills Clear Lake Coast Dairies Crystal Cove Cuyamaca Rancho D. L. Bliss Del Norte Coast Redwoods Donner Memorial Dos Rios Ranch Ed Z'berg Sugar Pine Point Emerald Bay The Forest of Nisene Marks Fort Ord Dunes Fremont Peak Garrapata Gaviota Great Valley Grasslands Grizzly Creek Redwoods Grover Hot Springs Hearst San Simeon Hendy Woods Henry Cowell Redwoods Henry W. Coe Humboldt Lagoons Humboldt Redwoods Jedediah Smith Redwoods Julia Pfeiffer Burns Leo Carrillo Limekiln MacKerricher Malibu Creek Manchester McArthur–Burney Falls Memorial McLaughlin Eastshore Mendocino Headlands Mendocino Woodlands Montaña de Oro Morro Bay Mount Diablo Mount San Jacinto Mount Tamalpais Navarro River Redwoods Pacheco Palomar Mountain Pfeiffer Big Sur Placerita Canyon Plumas-Eureka Point Mugu Portola Redwoods Prairie Creek Redwoods Red Rock Canyon Richardson Grove Rio de Los Angeles Robert Louis Stevenson Russian Gulch Saddleback Butte Salt Point Samuel P. Taylor San Bruno Mountain Sinkyone Wilderness South Yuba River Sue-meg Sugarloaf Ridge Sutter Buttes Tolowa Dunes Tomales Bay Topanga Trione-Annadel Van Damme Washoe Meadows Wilder Ranch
State Natural Reserves	Antelope Valley California Poppy Armstrong Redwoods Azalea Caspar Headlands John B. Dewitt John Little Jug Handle Kruse Rhododendron Los Osos Oaks Mailliard Redwoods Mono Lake Tufa Montgomery Woods Point Lobos Smithe Redwoods Torrey Pines Tule Elk
State Marine Reserves	Albany Anacapa Island SMR Asilomar Begg Rock Big Creek Bodega Head Cabrillo Carmel Pinnacles Carrington Point Del Mar Landing Elkhorn Slough Emeryville Crescent Estero de Limantour and Drakes Estero Fitzgerald Gerstle Cove Gull Island Harris Point Judith Rock Laguna Beach Long Point Lovers Point Montara and Pillar Point Moro Cojo Slough Morro Bay Natural Bridges Piedras Blancas Point Arena Point Buchon Point Cabrillo Point Dume Point Lobos Point Reyes Point Sur Richardson Rock Russian River Santa Barbara Island Scorpion Sea Lion Gulch Skunk Point South Cape Mendocino Stewarts Point Vandenberg
State Historic Parks	Anderson Marsh Antelope Valley Indian Museum Bale Grist Mill Benicia Capitol Bidwell Mansion Bodie California Citrus California State Indian Museum Chumash Painted Cave Colonel Allensworth Columbia El Presidio de Santa Barbara Empire Mine Folsom Powerhouse Fort Humboldt Fort Ross Fort Tejon Governor's Mansion Hearst Castle Indian Grinding Rock Jack London La Purísima Mission Leland Stanford Mansion Los Angeles Los Encinos Malakoff Diggins Marconi Conference Center Marsh Creek Marshall Gold Discovery Monterey Old Sacramento Old Town San Diego Olompali Pigeon Point Light Station Pío Pico Point Sur Railtown 1897 Rancho Petaluma Adobe San Juan Bautista San Pasqual Battlefield Santa Cruz Mission Santa Susana Pass Shasta Sonoma Sutter's Fort Tomo-Kahni Wassama Round House Watts Towers Weaverville Joss House Will Rogers William B. Ide Adobe Woodland Opera House
State Beaches	Asilomar Bean Hollow Bolsa Chica Cardiff Carlsbad Carmel River Carpinteria Caspar Headlands Cayucos Corona del Mar Crown Memorial Dockweiler Doheny El Capitán Emma Wood Gray Whale Cove Greenwood Half Moon Bay Huntington Leucadia Lighthouse Field Little River Malibu Lagoon Mandalay Manresa Marina McGrath Montara Monterey Moonlight Morro Strand Moss Landing Natural Bridges New Brighton Pacifica Pelican Pescadero Pismo Point Dume Point Sal Pomponio Refugio Robert H. Meyer Memorial Salinas River San Buenaventura San Clemente San Elijo San Gregorio San Onofre Santa Monica Schooner Gulch Seacliff Silver Strand Sonoma Coast South Carlsbad Sunset Thornton Torrey Pines Trinidad Twin Lakes Westport-Union Landing Will Rogers William Randolph Hearst Memorial Zmudowski
State Recreation Areas	Admiral William Standley Auburn Austin Creek Benbow Benicia Bethany Reservoir Brannan Island Candlestick Point Castaic Lake Colusa-Sacramento River Folsom Lake Franks Tract George J. Hatfield Harry A. Merlo Kenneth Hahn Kings Beach Lake Del Valle Lake Oroville Lake Perris Lake Valley Martial Cottle McConnell Millerton Lake Picacho Providence Mountains Salton Sea San Luis Reservoir Silverwood Lake Standish-Hickey Tahoe Turlock Lake Woodson Bridge
State Vehicular Recreation Areas	Carnegie Clay Pit Heber Dunes Hollister Hills Hungry Valley Oceano Dunes Ocotillo Wells Prairie City
Other	Burleigh H. Murray Ranch California State Capitol Museum California State Mining and Mineral Museum California State Railroad Museum Castro Adobe Delta Meadows Estero Bay Hatton Canyon Indio Hills Palms Point Cabrillo Light Ishxenta State Park Point Montara Light Reynolds Wayside Campground San Timoteo Canyon Stone Lake Verdugo Mountains Ward Creek Wildwood Canyon

National Forests and Grasslands

National Forests and Grasslands	Angeles Butte Valley NG Cleveland Eldorado Humboldt–Toiyabe Inyo Klamath Lake Tahoe Basin Lassen Los Padres Mendocino Modoc Plumas Rogue River–Siskiyou San Bernardino Sequoia Shasta–Trinity Sierra Six Rivers Stanislaus Tahoe
National Wilderness Preservation System	Agua Tibia Ansel Adams Bucks Lake Caribou Carson–Iceberg Castle Crags Cucamonga Desolation Dick Smith Dinkey Lakes Emigrant Golden Trout Hoover Inyo Mountains Ishi Jennie Lakes John Muir Kaiser Marble Mountain Mokelumne Mount Shasta Wilderness North Fork Pine Creek San Gabriel San Jacinto San Rafael Sanhedrin Sespe Siskiyou Snow Mountain South Fork Eel River South Sierra South Warner Thousand Lakes Trinity Alps Ventana Yolla Bolly–Middle Eel Yuki
National Monuments and Recreation Areas	Giant Sequoia National Monument San Gabriel Mountains National Monument Sand to Snow National Monument Santa Rosa and San Jacinto Mountains National Monument Smith River National Recreation Area Whiskeytown–Shasta–Trinity National Recreation Area

State Forests
Boggs Mountain Demonstration Ellen Pickett Jackson Demonstration Las Posadas LaTour Demonstration Mount Zion Demonstration Mountain Home Demonstration Soquel Demonstration

National Wildlife Refuges

State Wildlife Areas

Wildlife Areas	Antelope Valley Ash Creek Bass Hill Battle Creek Big Lagoon Big Sandy Biscar Butte Valley Buttermilk Country Cache Creek Camp Cady Cantara/Ney Springs Cedar Roughs Cinder Flats Collins Eddy Colusa Bypass Coon Hollow Cottonwood Creek Crescent City Marsh Crocker Meadows Daugherty Hill Decker Island Doyle Dutch Flat Eastlker River Eel River Elk Creek Wetlands Elk River Fay Slough Feather River Fitzhugh Creek Fremont Weir Grass Lake Gray Lodge Green Creek Grizzly Island Hallelujah Junction Heenan Lake Hill Slough Hollenbeck Canyon Honey Lake Hope Valley Horseshoe Ranch Imperial Indian Valley Kelso Peak and Old Dad Mountains Kinsman Flat Knoxville Laguna Lake Berryessa Lake Earl Lake Sonoma Little Panoche Reservoir Los Banos Lower Sherman Island Mad River Slough Marble Mountains Mendota Merrill's Landing Miner Slough Monache Meadows Morro Bay Moss Landing Mouth of Cottonwood Creek Napa-Sonoma Marshes North Grasslands O'Neill Forebay Oroville Petaluma Marsh Pickel Meadow Pine Creek Point Edith Putah Creek Rector Reservoir Red Lake Rhode Island Sacramento River San Felipe Valley San Jacinto San Luis Obispo San Luis Reservoir San Pablo Bay Santa Rosa Shasta Valley Silver Creek Slinkard/Little Antelope Smithneck Creek South Fork Spenceville Surprise Valley Sutter Bypass Tehama Truckee River Upper Butte Basin Volta Warner Valley Waukell Creek West Hilmar Westlker River White Slough Willow Creek Yolo Bypass
Ecological Reserves	Albany Mudflats Alkali Sink Allensworth Atascadero Creek Marsh Bair Island Baldwin Lake Batiquitos Lagoon Blue Sky Boden Canyon Boggs Lake Bolsa Chica Bonny Doon Buena Vista Lagoon Butler Slough Butte Creek Canyon Butte Creek House Buttonwillow By Day Creek Calhoun Cut Canebrake Carlsbad Highlands Carmel Bay Carrizo Canyon Carrizo Plains China Point Clover Creek Coachella Valley Coal Canyon Corte Madera Marsh Crestridge Dairy Mart Ponds Dales Lake Del Mar Landing Eden Landing Elkhorn Slough Estelle Mountain Fall River Mills Fish Slough Fremont Valley Goleta Slough Indian Joe Spring Kaweah Kerman King Clone Laguna Laurel Loch Lomond Vernal Pool Lokern Magnesia Spring Marin Islands Mattole River McGinty Mountain Morro Dunes Morro Rock Napa River North Table Mountain Oasis Spring Panoche Hills Peytonia Slough Phoenix Vernal Pools Pine Hill Piute Creek Pleasant Valley Rancho Jamul Redwood Shores River Springs Lakes Saline Valley San Dieguito Lagoon San Elijo Lagoon San Felipe Creek San Joaquin River Santa Rosa Plateau Springville Stone Corral Sycamore Canyon Sycuan Peak Thomes Creek Tomales Bay Upper Newport Bay Watsonville Slough West Mojave Desert Woodbridge Yaudanchi
Marine Protected Areas	Abalone Cove and Point Vicente Anacapa Island SMCA Año Nuevo Arrow Point to Lion Head Point Batiquitos Lagoon Big Creek Bodega Head Bolsa Chica Cambria Campus Point Carmel Bay Cat Harbor Crystal Cove Dana Point Duxbury Reef Edward F. Ricketts Elkhorn Slough Estero Americano Estero de Limantour and Drakes Estero Estero de San Antonio Fagan Marsh Famosa Slough Farnsworth Onshore and Offshore Goleta Slough Greyhound Rock Lovers Cove and Casino Point MacKerricher Marin Islands Morro Bay Naples Pacific Grove Marine Gardens Painted Cave Piedras Blancas Point Arena Point Buchon Point Dume Point Reyes Point Sur Portuguese Ledge Pyramid Point Robert E. Badham Robert W. Crown Russian Gulch Russian River Salt Point San Diego-Scripps San Dieguito Lagoon San Elijo Lagoon Saunders Reef Sea Lion Cove Sonoma Coast Soquel Canyon South La Jolla South Point Southeast Farallon Island Stewarts Point Swami's Tijuana River Mouth Upper Newport Bay Van Damme Vandenberg White Rock (Cambria)

Bureau of Land Management National Conservation Lands

National Monuments	Berryessa Snow Mountain California Coastal Carrizo Plain Cascade–Siskiyou Fort Ord Mojave Trails Sand to Snow Santa Rosa and San Jacinto Mountains
National Conservation Areas	California Desert King Range
Wilderness Areas	Argus Range Big Maria Mountains Bigelow Cholla Garden Bighorn Mountain Black Mountain Bright Star Bristol Mountains Cadiz Dunes Carrizo Gorge Chemehuevi Mountains Chimney Peak Chuckwalla Mountains Chumash Cleghorn Lakes Clipper Mountain Coso Range Coyote Mountains Darwin Falls Dead Mountains Dick Smith El Paso Mountains Fish Creek Mountains Funeral Mountains Garcia Golden Valley Grass Valley Headwaters Forest Reserve Hollow Hills Ibex Indian Pass Inyo Mountains Jacumba Kelso Dunes Kiavah Kingston Range Little Chuckwalla Mountains Little Picacho Machesna Mountain Malpais Mesa Manly Peak Matilija Mecca Hills Mesquite Newberry Mountains Nopah Range North Algodones Dunes North Mesquite Mountains Old Woman Mountains Orocopia Mountains Otay Mountain Owens Peak Pahrump Valley Palen/McCoy Palo Verde Mountains Picacho Peak Piper Mountain Piute Mountains Red Buttes Resting Spring Range Rice Valley Riverside Mountains Rodman Mountains Sacatar Trail Saddle Peak Hills San Gorgonio Santa Lucia Santa Rosa Sawtooth Mountains Sespe Sheephole Valley South Nopah Range Stateline Stepladder Mountains Surprise Canyon Sylvania Mountains Trilobite Turtle Mountains Whipple Mountains