California Seafloor Mapping Program Central Coast Marine Protected Areas Contents Central Coast MPA’S SMCA SMR
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California Seafloor Mapping Program Central Coast Marine Protected Areas Contents Central Coast MPA’s SMCA SMR Año Nuevo SMCA 6-7 Greyhound Rock SMCA Soquel Canyon SMCA 8-9 California Seafloor Mapping Program 4-5 Portugese Ledge SMCA & Central Coast MPA’s Edward F. Ricketts SMCA California MPA network design 26-27 Lovers Point SMR Pacific Grove Marine Gardens SMCA California MPA raw data 28-29 10-11 Asilomar SMR Acknowledgemnts 30-31 Carmel Pinnacles SMR Carmel Bay SMCA Pt. Lobos SMCA/SMR 12-13 Pt. Sur SMCA/SMR 14-15 Big Creek SMCA/SMR 16-17 California Central Coast Marine Protected Areas Piedras Blancas SMCA/SMR 18-19 Cambria SMCA White Rock Cambria SMCA 20-21 Pt. Buchon SMCA/SMR 22-23 Vandenberg SMR 24-25 0 25 km 50 km “…and some rin up hill and down dale, knapping the chucky stanes to pieces wi’ hammers, like sa mony road-makers run daft. They say ‘tis to see how the world was made!” Sir Walter Scott, St.Ronan’s Well, 1824 energy, as well as the basemap for applied and basic 24-25). Following the maps we have highlighted complex mosaic of diverse physical features. This research; the driving force behind the CSMP has some recent advances in science using CSMP data new knowledge is providing the foundation for been California’s Marine Life Protection Act (MLPA) to understand how habitats are used by biological improved understanding and management of the rich and its mandate to create the nation’s first Marine communities (pages 28-31). diversity of marine habitats, species and ecosystems Protected Area (MPA) network. Because Califor- found along California’s coast. Modern studies of nia’s MPA network is required by law to capture GEOLOGY AND HABITAT OF THE canyon erosion suggest that the canyons are mainly Carmel Bay representative amounts of regional seafloor bottom CENTRAL COAST cut and enlarged by submarine processes that types (rocky and sedimentary habitats) within four include landslides, turbidity currents, and fluid seeps. depth zones (0-30m, 30-100m, 100-200m, and > The distribution of marine species is governed Each canyon provides a range of submarine land- California Seafloor Mapping 200m), the initial CSMP product development has by gradients (e.g., temperature and depth), but also scapes, including canyon walls, floors, and terraces. In Program and Central Coast MPA’s focused on the classification and delineation of these by the substrate distribution (e.g., rocks and sand). general, the continental shelf accumulates and stores basic seafloor habitat types within state waters. The Thus, documenting the substrate and how it changes sediment, while the canyons provide the sediment The purpose of this publication is to present MLPA adopted this approach because California’s through time is just as vital to resource manage- pathway between shallow shelf environments and a general overview of the seafloor habitats found rich marine biodiversity is a direct result of the wide ment as monitoring other parameters. The shallow broad depositional settings on the deep basin floor within each of the Marine Protected Areas (MPAs) range of habitats found within state waters. geology (surface deposits and shallow rocks) and located much farther offshore. comprising the Central Coast Region of California’s geomorphology (landforms and landscapes) of a State-wide MPA Network. The maps and habitat This mapping effort has been largely success- region constitute the immutable background context A closer look at the shallow continental shelf information presented are products of the California ful in completing the CSMP data acquisition along for modern physical and biological processes. reveals much detail that is important to marine Ocean Protection Council’s (OPC) California Sea- the mainland coast, with the exception of a critical communities, species and individual organisms. floor Mapping Program (CSMP). data gap in the extreme nearshore where up until While much of the geological context is The substrate can be divided into a range of rock recently surf, kelp and rocky shoals precluded the unchanging over millennia, many physical variables types and sediment veneers that provide a great Initiated in 2005, the California Seafloor Map- use of conventional mapping methods. As a result, evolve on a timeframe of direct interest to resource range of shapes and textures, each important for ping Program is the first comprehensive mapping a significant portion of the shallow depth zone in managers. Rocky regions can expand or contract as specific kinds of marine life. The flat sandy plains of a state’s entire territorial sea in our nation’s many of the MPAs has not been mapped, but new sand alternately buries or reveals the local bedrock of the shallow continental shelf vary in grain size, history. The ultimate goal of CSMP is the creation techniques developed during the course of the crags. Submarine canyon processes sporadically presence and size of ripples and dunes, frequency of of onshore and offshore habitat and geology maps. sediment transport, and the presence of enigmatic Funded largely by the OPC through State Proposi- “rippled scour depressions.” Bedrock outcrops are tectonic mixture of many different rock types that tion 84 bond funds, with additional contributions more geomorphically diverse. Hard bedrock offers were scraped onto the North American plate from from NOAA, private industry, state and federal a broad range of topography and surface details, a subducting oceanic plate. The formation owes agencies, and NGO’s; the CSMP was conducted including fractures, faults, cliffs, plateaus, mounds, sea its great diversity of textures and structures to the by a collaborative team of experts from resource mounts, parallel ridges, joints, and surface rough- variable hardness and structures of the rocks that management agencies, private industry and academia. ness. In shallow waters, bedrock locally provides the compose the formation. Franciscan Formation The products from the CSMP include a wide anchorage for broad kelp forests and kelp-dependent comprises conglomerate, sandstone, shale, chert, variety of digital map layers derived primarily from communities. limestone, basalt, serpentine, and high-pressure multibeam echo sounder bathymetry, sub-bottom metamorphic rocks. The Neogene sedimentary beds profiling sonar, and video and still imagery data of The shallow continental shelf of California (15 to 3 Ma) include several formations, including the seafloor. The results and products from the shown in this publication includes four main Monterey Shale, Purisima Formation, Santa Cruz CSMP include a wide variety of digital map layers substrate types: 1) Mesozoic and Cenozoic granitic Mudstone, and the Pismo Formation. These geologic derived primarily from multibeam echo sounder rocks, 2) Mesozoic Franciscan Formation, 3) Neo- units create a unique marine habitat: long, sinuous bathymetry, sub-bottom profiling sonar, video and gene sedimentary beds, and 4) modern sediment parallel ridges and valleys that are locally folded, still imagery data of the seafloor. These products are cover that locally buries the bedrock substrate. faulted, and fractured. The ridges are sedimentary being made publically available through a variety of The CSMP also contributed to workforce development with dozens of California State University, Granitic rocks are exposed between Pacific Grove beds that are relatively stronger than the beds form- Monterey Bay students trained in state-of-the-art seafloor mapping technology participating in venues including: a comprehensive folio map series CSMP data collection and map product creation. Many of the graduates now fill important marine and Point Lobos; Franciscan rocks are exposed ing the intervening valleys. being created by the United State Geological Survey spatial planning positions at state and national levels. between Point Sur and San Luis Obispo; sedimentary (USGS), incorporation into the GoogleEarth Globe, rocks are exposed in many locations; and, sedimen- All of the bedrock units described above lo- and as downloadable GIS data layers at the websites CSMP now make it possible to fill this data gap (see disturb the canyon walls and floor. Strong currents tary cover is ubiquitous. The geologic ages of these cally provide plateaus, small cliffs, overhangs, and of the CSUMB Seafloor Mapping Lab, USGS and the page 26). continually rearrange the location of coarse and fine different formations, generalized below, are typically a network of interconnected valleys. The physical National Geodetic Data Center (NGDC). sand substrate on the shelf. expressed as millions of years before present, or complexity arises in part from the presence of Depth Sediment Rock Here we provide descriptions and maps from “mega annum,” abbreviated “Ma.” ubiquitous tectonic faults, folds, and fractures that 0-30 m While the CSMP was launched to meet a diverse the CSMP depicting the basic geology and MLPA Prior to the CSMP, California’s submerged conti- are a product of millions of years of stress between 30-100 m set of critical state marine management needs, habitats found in the MPAs of the Central Coast nental shelf was generally regarded as a relatively flat, Granitic rocks (80 Ma) form a hard substrate the North American and Pacific plates. While the 100-200 m including identifying hazards to navigation, assess- Region extending from the Año Nuevo State Marine featureless surface cut by numerous deep submarine with an interconnected labyrinth of deep faults and onshore San Andreas Fault is the best example of > 200 m ing earthquake and tsunami risks, modeling coastal Conservation Area (SMCA) in the north (see pages canyons. Now, with the remarkable seafloor detail fractures. The fractures form when brittle granitic how these tectonic forces can break rocks apart, erosion and sea level rise, making wiser develop- 6-7) to the Vandenberg State Marine Reserve (SMR) unveiled by the CSMP and presented in this volume, rocks expand during their slow rise to the surface there are also active faults on the continental shelf 0 25 km 50 km ment decisions, exploring the potential for off-shore near Point Conception in the south (see pages California’s continental shelf is revealed as a highly of the Earth.