117 original plate boundaries from Esri Data and Maps (2007) edited to better match 10 years of earthquakes, land forms and bathymetry from Mapping Our World's WSI_Earth image from module 2. Esri Canada's education layer of plate boundaries and the Smithsonian's ascii file from the download section of the 'This Dynamic Planet' site plate boundaries were used to compare the resulting final plate boundaries for significant differences.

The Earth’s lithosphere is made up of a series of plates that float on the mantle. Scientists think the convection of the mantle causes these plates to move triggering earthquakes, volcanoes, mountain-building events, or trench formation. These plates creep along at a rate of approximately five to ten centimeters (two to four inches) per year. These plates move in primarily three main ways. They slide past one another along transform (strike-slip) boundaries, they push against each other at convergent boundaries, or pull away in opposite directions at divergent boundaries. Each one of these interactions create different types of landforms. For example, the steady pressure of the Indian Plate and the Eurasian Plate built the Himalaya mountains and the Plateau of Tibet. The divergent boundary between the African Plate and the Arabian formed the Red Sea.Use this plate map layer to explore how the movement of the plates cause earthquakes, volcanoes, or shape Earth’s landscape.

This map layer features both major and minor plates, but excludes microplates. The data is from the scientific study by Peter Bird published in volume 4, issue 3 of Geochemisty, Geophysics, Geosystems and was translated into geospatial formats by Hugo Ahlenius and updated by Dan Pisut.

The global tectonics data compilation is a set of raster and vector data that are useful for investigating tectonics past and present. The datasets are useful on their own or can be used in GIS software, which includes the QGIS project file for convenience. The datasets include our new models for tectonic plate boundaries and deformation zones, geologic provinces and orogens. Additional datasets include earthquake and volcano locations, geochronology, topography, magnetics, gravity, and seismic velocity.

The global tectonics collection is suitable for research and educational purposes.

This map can be used:- to study the motion of the plates- to study phenomena taking place at plate boundaries- to visualize processes taking place.

The surface of the Earth is broken up into large plates. There are seven major plates: North America, South America, Eurasia, Africa, India, the Pacific, and Antarctica. There are also numerous microplates. The number and shapes of the plates change over geologic time. Plates are divided by boundaries that are seismically active. The different plate boundaries can be described by the type of motion that is occurring between the plates at specific locations. Ocean basins contain spreading ridges where the youngest portions of the seafloor are found. At the spreading ridges magma is released as it pushes up from the mantle and new oceanic crust is formed. At subduction zone boundaries plates are moving toward each other, with one plate subducting or moving beneath the other. When this occurs the crust is pushed into the mantle where it is recycled into magma.Data accessed from here: https://www-udc.ig.utexas.edu/external/plates/data.htm

Named Landforms of the World version 2 (NLWv2) contains four sub-layers representing geomorphological landforms, provinces, divisions, and their respective cartographic boundaries. The latter supports map making, while the first three represent basic units, such as landforms, which comprise provinces, and provinces comprise divisions. NLW is a substantial update to World Named Landforms in both compilation method and the attributes that describe each landform. For more details, please refer to our paper, Named Landforms of the World: A Geomorphological and Physiographic Compilation, in Annals of the American Association of Geographers. July 2, 2025: We have made Named Landforms of the World v3 (NLWv3) available. Please explore this group containing all of the layers and data. NLWv2 will remain available. Landforms are commonly defined as natural features on the surface of the Earth. The National Geographic Society specifies terrain as the basis for landforms and lists four major types: mountains, hills, plateaus, and plains. Here, however, we define landforms in a richer way that includes properties relating to underlying geologic structure, erosional and depositional character, and tectonic setting and processes. These characteristics were asserted by Dr. Richard E. Murphy in 1968 in his map, titled Landforms of the World. We blended Murphy"s definition for landforms with the work E.M. Bridges, who in his 1990 book, World Geomorphology, provided a globally consistent description of geomorphological divisions, provinces, and sections to give names to the landform regions of the world. AttributeDescriptionBridges Full NameFull name from E.M. Bridges" 1990 "World Geomorphology" Division and if present province and section - intended for labeling print maps of small extents. Bridges DivisionGeomorphological Division as described in E.M. Bridges" 1990 "World Geomorphology" - All Landforms have a division assigned, i.e., no nulls. Bridges ProvinceGeomorphological Province as described in E.M. Bridges" 1990 "World Geomorphology" - Not all divisions are subdivided into provinces. Bridges SectionGeomorphological Section as described in E.M. Bridges" 1990 "World Geomorphology" - Not all provinces are subdivided into sections.StructureLandform Structure as described in Richard E. Murphy"s 1968 "Landforms of the World" map. Coded Value Domain. Values include: - Alpine Systems: Area of mountains formed by orogenic (collisions of tectonic plates) processes in the past 350 to 500 million years. - Caledonian/Hercynian Shield Remnants: Area of mountains formed by orogenic (collisions of tectonic plates) processes 350 to 500 million years ago. - Gondwana or Laurasian Shields: Area underlaid by mostly crystalline rock formations fromed one billion or more years ago and unbroken by tectonic processes. - Rifted Shield Areas: fractures or spreading along or adjacent to tectonic plate edges. - Isolated Volcanic Areas: volcanic activity occurring outside of Alpine Systems and Rifted Shields. - Sedimentary: Areas of deposition occurring within the past 2.5 million years Moist or DryLandform Erosional/Depositional variable as described in Richard E. Murphy"s 1968 "Landforms of the World" map. Coded Value Domain. Values include: - Moist: where annual aridity index is 1.0 or higher, which implies precipitation is absorbed or lost via runoff. - Dry: where annual aridity index is less than 1.0, which implies more precipitation evaporates before it can be absorbed or lost via runoff. TopographicLandform Topographic type variable as described in Richard E. Murphy"s 1968 "Landforms of the World" map. Karagulle et. al. 2017 - based on rich morphometric characteristics. Coded Value Domain. Values include: - Plains: Areas with less than 90-meters of relief and slopes under 20%. - Hills: Areas with 90- to 300-meters of local relief. - Mountains: Areas with over 300-meters of relief - High Tablelands: Areas with over 300-meters of relief and 50% of highest elevation areas are of gentle slope. - Depressions or Basins: Areas of land surrounded land of higher elevation. Glaciation TypeLandform Erosional/Depositional variable as described in Richard E. Murphy"s 1968 "Landforms of the World" map. Values include: - Wisconsin/Wurm Glacial Extent: Areas of most recent glaciation which formed 115,000 years ago and ended 11,000 years ago. - Pre-Wisconsin/Wurm Glacial Extent: Areas subjected only to glaciation prior to 140,000 years ago. ContinentAssigned by Author during data compilation. Bridges Short NameThe name of the smallest of Division, Province, or Section containing this landform feature. Murphy Landform CodeCombination of Richard E. Murphy"s 1968 "Landforms of the World" variables expressed as a 3- or 4- letter notation. Used to label medium scale maps. Area_GeoGeodesic area in km2. Primary PlateName of tectonic plate that either completely underlays this landform feature or underlays the largest portion of the landform"s area.Secondary PlateWhen a landform is underlaid by two or more tectonic plates, this is the plate that underlays the second largest area.3rd PlateWhen a landform is underlaid by three or more tectonic plates, this is the plate that underlays the third largest area.4th PlateWhen a landform is underlaid by four or more tectonic plates, this is the plate that underlays the fourth largest area.5th PlateWhen a landform is underlaid by five tectonic plates, this is the plate that underlays the fifth largest area.NotesContains standard text to convey additional tectonic process characteristics. Tectonic ProcessAssigns values of orogenic, rift zone, or above subducting plate. These data are also available as an ArcGIS Pro Map Package: Named_Landforms_of_the_World_v2.0.mpkx.These data supersede the earlier v1.0: World Named Landforms. Change Log:DateDescription of ChangeJuly 20, 2022Corrected spelling of Guiana from incorrect representation, "Guyana", used by Bridges.July 27, 2022Corrected Structure coded value domain value, changing "Caledonian/Hercynian Shield" to "Caledonian , Hercynian, or Appalachian Remnants". Cite as: Frye, C., Sayre R., Pippi, M., Karagulle, Murphy, A., D. Soller, D.R., Gilbert, M., and Richards, J., 2022. Named Landforms of the World. DOI: 10.13140/RG.2.2.33178.93129. Accessed on:

This story map tells the tale of Earth’s tectonic plates, their secret conspiracies, awe-inspiring exhibitions and subtle impacts on the maps and geospatial information we so often take for granted as unambiguous. But is it? We recommend you journey through this map on the trail we’ve manicured on the left. You will find yourself hovering over the Mid-Atlantic Ridge or swimming in magma deep within the Earth’s core. Have fun and we hope your voyage is fruitful!

This feature service depicts the boundaries of the Earth's tectonic plates and major fault lines and areas.Tectonic plates are large plates of rock that make up the foundation of the Earth's crust and the shape of the continents. The plates comprise the bottom of the crust and the top of the Earth's mantle. The plates are most famously known for being the source of earthquakes.A fault is a fracture or discontinuity in a volume of rock, across which there has been significant displacement as a result of earth movement. Large faults within the Earth's crust result from the movement of tectonic plates.Feature service published and hosted by Esri Canada © 2020.Content Source(s):Plates, United States Geological Survey (USGS)Fault Lines, United States Geological Survey(USGS)Coordinate System: Web Mercator Auxiliary Sphere (WKID 102100)This work is licensed under the Web Services and API Terms of Use.View Summary | View Terms of Use This data is licensed under a Creative Commons Attribution-NonCommercial 2.5 Canada License

This layer shows the interpreted surface locations of active plate and microplate boundaries, in and around Te Riu-a-Māui / Zealandia. The layer was newly-compiled for, and is part of, the 'Tectonic map of Te Riu-a-Māui / Zealandia' 1:8 500 000 dataset.

A web application for use in explaining the global distribution of earthquakes and volcanoes and why they are located where they are - specifically designed for use with NCEA Level 1 Geography.Layers that can be turned on in this application:- Tectonic Plate Boundaries- Recent Earthquakes- Archived Earthquakes- Global VolcanoesStudents can export their maps to a PDF or screenshot their maps.You do not have to have an ArcGIS Schools Bundle to access this web application.

This digital dataset release of the Tectonic Map of the Colorado Plateau is a courtesy publication of the previously published legacy report by V.C. Kelley in 1955. The original publication, "Tectonic Map of the Colorado Plateau Showing Uranium Deposits" contains elevation contours from the top of the Chinle formation in 1000 ft intervals and geologic structural formations such as monoclinal, synclinal, and anticlinal structures. The digitizing of this map is to provide a more accessible dataset to be available for public usage. The original dataset was in relation to a larger project by the University of New Mexico and their publications in geology of uranium distributions throughout the Colorado Plateau (Kelley, V.C., 1955, Regional tectonics of the Colorado Plateau and relationship to the origin and distribution of uranium: Albuquerque, University of New Mexico, Publications in Geology no. 5, 120 p., 1 sheet, scale 1:1,000,000.). The entirety of this dataset includes both spatial and non-spatial data held in a singular, GeMS compliant geodatabase. This geodatabase includes a geologic map feature dataset holding fault lines, iso value lines, structure contours, and other geologic lines; nonspatial data recorded in standalone tables such as a description of map units, glossary, data source reference, geomaterials dictionary, and their entities and attributes. Data source references include web links to published standards, data dictionaries, and any other referenced data within the published map. There is a final nonspatial table that is in reference to the original digitized and identified geologic structures per the legacy map plate, these structures were broken up by state (Arizona, Colorado, New Mexico, and Utah) with each structure given a numerical value (starting at 1, for each individual state) these structures were compiled into a synchronous excel document to provide a digital record of those structures and features listed on the legacy map plate.

The NLWv3 Tectonic Plates layer contains features are produced based on assigning each NLWv3 landform feature the topmost tectonic plate and then using ArcGIS's Dissolve geoprocessing tool to create multipart polygons representing the area of each of the topmost plates.Tectonic plates are the building blocks of continents and comprise the Earth's crust. Tectonic plates float, moving slowly in the outer layers of the Earth's mantle. Tectonic plates cover the entire Earth's surface and their respective movements creates three types of boundaries: Divergent: The plates are moving away from each other causing new crust to emerge. Such boundaries are usually referred to as rift zones.Convergent: The plates are colliding in one of two ways. The first is when the edges of both plates uplift to cause mountains to rise and the second is subducting where one plate slides beneath the other, causing it to rise. Transform: These plates slide past each other in opposite directions.The boundaries of tectonic plates are where earthquakes, most volcanoes, and rough mountainous terrain are produced. We evaluated the most recently produced digital tectonic plate boundary datasets. The NLWv3 compilation based is first based on Ahlenius and then we adjusted many of the boundaries to match more recent seafloor rift and landform boundaries. We also added the Sinai and Adriatic Sea plates. Ahlenius, H. 2014. World tectonic plates and boundaries. Accessed December 22, 2021. https://github.com/fraxen/tectonicplatesTectonic map of the world. Accessed April 5, 2022. https://www.datapages.com/gis-map-publishing-program/gis-open-files/global-framework/tectonic-map-of-the-world-2007.Bird, P. 2003. An updated digital model of plate boundaries. Geochemistry, Geophysics, Geosystems 4 (3):1–46. doi: 10.1029/2001GC000252.Gaba, E. 2018. Tectonic plates boundaries World Map Wt 180degE centered-en.svg. Accessed June 2, 2022. https://en.wikipedia.org/wiki/File:Tectonic_plates_boundaries_World_map_Wt_180degE_centered-en.svgHasterok, D., J. A. Halpin, A. S. Collins, M. Hand, C. Kreemer, M. G. Gard, and S. Glorie. 2022. New maps of global geological provinces and tectonic plates. Earth-Science Reviews 231:104069. doi: 10.1016/j.earscirev.2022.104069.

This map depicts one year of global earthquakes and plate boundaries. Click on an earthquake for details about that event. Data is from the USGS Earthquake Catalog.If you have questions about the table, read the documentation from the USGS.

Atlas of Ordovician plate tectonic and paleogeographic maps (Early Tremadoc, 485 Ma), part 1.

This map presents a model of crustal strain rates derived from Global Positioning System (GPS) measurements of horizontal station velocities. The model indicates the spatial distribution of deformation rates within the Pacific North America plate boundary from the San Andreas fault system in the west to the Basin and Range province in the east. As these strain rates are derived from data spanning the last two decades, the model reflects a best estimate of present day deformation. To download the map, please see the link provided.

The 2011 Bedrock Geologic Map of Vermont (1:100,000 scale) was created to integrate detailed (1:12,000- to 1:24,000-scale) modern mapping with the theory of plate tectonics to provide a framework for geologic, tectonic, economic, hydrogeologic, and environmental characterization of the bedrock of Vermont. It supersedes the 1961 bedrock geologic map which was produced at a scale of 1:250,000 (Doll and others, 1961).Please see the metadata and readme files at the publication website:https://pubs.usgs.gov/sim/3184/

The 2011 Bedrock Geologic Map of Vermont (1:100,000 scale) was created to integrate detailed (1:12,000- to 1:24,000-scale) modern mapping with the theory of plate tectonics to provide a framework for geologic, tectonic, economic, hydrogeologic, and environmental characterization of the bedrock of Vermont. It supersedes the 1961 bedrock geologic map which was produced at a scale of 1:250,000 (Doll and others, 1961).Please see the metadata and readme files at the publication website:https://pubs.usgs.gov/sim/3184/

the precise location and geometry of oceanic spreading centers and associated transform faults or discontinuities' boundary has fundamental implications in our understanding of oceanic accretion, the accommodation of deformation around rigid lithospheric blocks, and the distribution of magmatic and volcanic processes. the now widely used location of mid oceanic ridges worldwide, published by p. bird in 2003, can be updated based on recent publicly available and published ship-based multibeam swath bathymetry data (100-m resolution or better), now available to ~25% of the ocean seafloor, but covering a significant proportion of the mid-ocean ridge system (>70%).here we publish the mapridges database built under the coordination of cgmw (commission for the geological map of the world), with a first version v1.0 (06/2024) that provides high resolution and up-to-date datasets of mid-ocean ridge segments and associated transform faults, and follow-up updates that will also include non-transform offsets.the detailed mapping of individual mid oceanic ridge segments was conducted using gmrt (ryan et al., 2009) (version 4.2 for mapridges v1.0), other publicly available datasets (e.g., ncei, pangaea, awi), and existing literature. mapridges will be revised with the acquisition of additional datasets, new publications, and correction of any errors in the database.the mapridge database was built in a gis environment, where each feature holds several attributes specific to the dataset. we include three different georeferenced shapefile layers: 1) ridge segments, 2) transform faults, and 3) transform zones. the latest corresponds to zones of distributed strike-slip deformation that lack a well-defined fault localizing strain, but that are often treated as transform faults.1) the ridge segments layer contains 1461 segments with 9 attributes: area_loca: the name of the ridge system loc_short: the short form of the ridge system using 3 characters lat: the maximum latitude of the ridge segment long: the maximum longitude of the ridge segment length: the length of the ridge segment in meters confidence: the degree of confidence on digitization based on the availability of high-resolution bathymetry data: 1 = low to medium confidence, 2 = high confidence references: supporting references used for the digitization name_code: unique segment code constructed from the loc_short and lat attributes in degree, minute, second coordinate format name_lit: name of the segment from the literature if it exists2) the transform fault layer contains 260 segments with 4 attributes: name_tf: name of the transform fault according to the literature length: length of the transform fault in meters lat: the maximum latitude of the fault segment long: the maximum longitude of the fault segment3) the transform zone layer contains 10 segments with 4 attributes: name_tf: name of the transform zone according to the literature length: length of the transform fault in meters lat: the maximum latitude of the fault segment long: the maximum longitude of the fault segmentto facilitate revisions and updates of the database, relevant information, corrections, or data could be sent to b. sautter (benjamin.sautter@univ-ubs.fr) and j. escartín (escartin@geologie.ens.fr).

description: This part of DS 781 presents data for faults for the geologic and geomorphic map of the Offshore of Pacifica map area, California. The vector data file is included in "Faults_OffshorePacifica.zip," which is accessible from http://pubs.usgs.gov/ds/781/OffshorePacifica/data_catalog_OffshorePacifica.html. The Offshore of Pacifica map area straddles the right-lateral transform boundary between the North American and Pacific plates and is cut by several active faults that cumulatively form a distributed shear zone, including the San Andreas Fault, the eastern strand of the San Gregorio Fault, the Golden Gate Fault, and the Potato Patch Fault (sheets 8, 9; Bruns and others, 2002; Ryan and others, 2008). These faults are covered by Holocene sediments (mostly units Qms, Qmsb, Qmst) with no seafloor expression, and are mapped using seismic-reflection data (sheet 8). The San Andreas Fault is the primary plate-boundary structure and extends northwest across the map area; it intersects the shoreline 10 km north of the map area at Pacifica Lagoon, and 3 km south of the map area at Mussel Rock. This section of the San Andreas Fault has an estimated slip rate of 17 to 24 mm/yr (U.S. Geological Survey, 2010), and the devastating Great 1906 California earthquake (M 7.8) is thought to have nucleated on the San Andreas a few kilometers offshore of San Francisco within the map area (sheet 9; Bolt, 1968; Lomax, 2005). The San Andreas Fault forms the boundary between two distinct basement terranes, Upper Jurassic to Lower Cretaceous rocks of the Franciscan Complex to the east, and Late Cretaceous granitic and older metamorphic rocks of the Salinian block to the west. Franciscan Complex rocks (unit KJf, undivided) form seafloor outcrops at and north of Point Lobos adjacent to onland exposures. The Franciscan is divided into 13 different units for the onshore portion of this geologic map based on different lithologies and ages, but the unit cannot be similarly divided in the offshore because of a lack of direct observation and (or) sampling. Faults were primarily mapped by interpretation of seismic reflection profile data (see S-15-10-NC and F-2-07-NC). The seismic reflection profiles were collected between 2007 and 2010. References Cited Bolt, B.A., 1968, The focus of the 1906 California earthquake: Bulletin of the Seismological Society of America, v. 58, p. 457€“471. Bruns, T.R., Cooper, A.K., Carlson, P.R., and McCulloch, D.S., 2002, Structure of the submerged San Andreas and San Gregorio fault zones in the Gulf of Farallones as inferred from high-resolution seismic-reflection data, in Parsons, T. (ed.), Crustal structure of the coastal and marine San Francisco Bay region, California: U.S. Geological Survey Professional Paper 1658, p. 77€“117. Lomax, A., 2005, A reanalysis of the hypocentral location and related observations for the Great 1906 California earthquake: Bulletin of the Seismological Society of America, v. 95, p. 861€“877. Ryan, H.F., Parsons, T., and Sliter, R.W., 2008. Vertical tectonic deformation associated with the San Andreas fault zone offshore of San Francisco, California. Tectonophysics, 429 (1-2), p. 209€“224. U.S. Geological Survey and California Geological Survey, 2010, Quaternary fault and fold database for the United States, accessed April 5, 2012, from USGS website: http://earthquake.usgs.gov/hazards/qfaults/.; abstract: This part of DS 781 presents data for faults for the geologic and geomorphic map of the Offshore of Pacifica map area, California. The vector data file is included in "Faults_OffshorePacifica.zip," which is accessible from http://pubs.usgs.gov/ds/781/OffshorePacifica/data_catalog_OffshorePacifica.html. The Offshore of Pacifica map area straddles the right-lateral transform boundary between the North American and Pacific plates and is cut by several active faults that cumulatively form a distributed shear zone, including the San Andreas Fault, the eastern strand of the San Gregorio Fault, the Golden Gate Fault, and the Potato Patch Fault (sheets 8, 9; Bruns and others, 2002; Ryan and others, 2008). These faults are covered by Holocene sediments (mostly units Qms, Qmsb, Qmst) with no seafloor expression, and are mapped using seismic-reflection data (sheet 8). The San Andreas Fault is the primary plate-boundary structure and extends northwest across the map area; it intersects the shoreline 10 km north of the map area at Pacifica Lagoon, and 3 km south of the map area at Mussel Rock. This section of the San Andreas Fault has an estimated slip rate of 17 to 24 mm/yr (U.S. Geological Survey, 2010), and the devastating Great 1906 California earthquake (M 7.8) is thought to have nucleated on the San Andreas a few kilometers offshore of San Francisco within the map area (sheet 9; Bolt, 1968; Lomax, 2005). The San Andreas Fault forms the boundary between two distinct basement terranes, Upper Jurassic to Lower Cretaceous rocks of the Franciscan Complex to the east, and Late Cretaceous granitic and older metamorphic rocks of the Salinian block to the west. Franciscan Complex rocks (unit KJf, undivided) form seafloor outcrops at and north of Point Lobos adjacent to onland exposures. The Franciscan is divided into 13 different units for the onshore portion of this geologic map based on different lithologies and ages, but the unit cannot be similarly divided in the offshore because of a lack of direct observation and (or) sampling. Faults were primarily mapped by interpretation of seismic reflection profile data (see S-15-10-NC and F-2-07-NC). The seismic reflection profiles were collected between 2007 and 2010. References Cited Bolt, B.A., 1968, The focus of the 1906 California earthquake: Bulletin of the Seismological Society of America, v. 58, p. 457€“471. Bruns, T.R., Cooper, A.K., Carlson, P.R., and McCulloch, D.S., 2002, Structure of the submerged San Andreas and San Gregorio fault zones in the Gulf of Farallones as inferred from high-resolution seismic-reflection data, in Parsons, T. (ed.), Crustal structure of the coastal and marine San Francisco Bay region, California: U.S. Geological Survey Professional Paper 1658, p. 77€“117. Lomax, A., 2005, A reanalysis of the hypocentral location and related observations for the Great 1906 California earthquake: Bulletin of the Seismological Society of America, v. 95, p. 861€“877. Ryan, H.F., Parsons, T., and Sliter, R.W., 2008. Vertical tectonic deformation associated with the San Andreas fault zone offshore of San Francisco, California. Tectonophysics, 429 (1-2), p. 209€“224. U.S. Geological Survey and California Geological Survey, 2010, Quaternary fault and fold database for the United States, accessed April 5, 2012, from USGS website: http://earthquake.usgs.gov/hazards/qfaults/.

description: This part of DS 781 presents data for folds for the geologic and geomorphic map of the Offshore of Pacifica map area, California. The vector data file is included in "Folds_OffshorePacifica.zip," which is accessible from http://pubs.usgs.gov/ds/781/OffshorePacifica/data_catalog_OffshorePacifica.html. The Offshore of Pacifica map area straddles the right-lateral transform boundary between the North American and Pacific plates and is cut by several active faults that cumulatively form a distributed shear zone, including the San Andreas Fault, the eastern strand of the San Gregorio Fault, the Golden Gate Fault, and the Potato Patch Fault (sheets 8, 9; Bruns and others, 2002; Ryan and others, 2008). These faults are covered by Holocene sediments (mostly units Qms, Qmsb, Qmst) with no seafloor expression, and are mapped using seismic-reflection data (sheet 8). The San Andreas Fault is the primary plate-boundary structure and extends northwest across the map area; it intersects the shoreline 10 km north of the map area at Pacifica Lagoon, and 3 km south of the map area at Mussel Rock. This section of the San Andreas Fault has an estimated slip rate of 17 to 24 mm/yr (U.S. Geological Survey, 2010), and the devastating Great 1906 California earthquake (M 7.8) is thought to have nucleated on the San Andreas a few kilometers offshore of San Francisco within the map area (sheet 9; Bolt, 1968; Lomax, 2005). The San Andreas Fault forms the boundary between two distinct basement terranes, Upper Jurassic to Lower Cretaceous rocks of the Franciscan Complex to the east, and Late Cretaceous granitic and older metamorphic rocks of the Salinian block to the west. Franciscan Complex rocks (unit KJf, undivided) form seafloor outcrops at and north of Point Lobos adjacent to onland exposures. The Franciscan is divided into 13 different units for the onshore portion of this geologic map based on different lithologies and ages, but the unit cannot be similarly divided in the offshore because of a lack of direct observation and (or) sampling. Folds were primarily mapped by interpretation of seismic reflection profile data (see S-15-10-NC and F-2-07-NC). The seismic reflection profiles were collected between 2007 and 2010. References Cited Bolt, B.A., 1968, The focus of the 1906 California earthquake: Bulletin of the Seismological Society of America, v. 58, p. 457€“471. Bruns, T.R., Cooper, A.K., Carlson, P.R., and McCulloch, D.S., 2002, Structure of the submerged San Andreas and San Gregorio fault zones in the Gulf of Farallones as inferred from high-resolution seismic-reflection data, in Parsons, T. (ed.), Crustal structure of the coastal and marine San Francisco Bay region, California: U.S. Geological Survey Professional Paper 1658, p. 77€“117. Lomax, A., 2005, A reanalysis of the hypocentral location and related observations for the Great 1906 California earthquake: Bulletin of the Seismological Society of America, v. 95, p. 861€“877. Ryan, H.F., Parsons, T., and Sliter, R.W., 2008. Vertical tectonic deformation associated with the San Andreas fault zone offshore of San Francisco, California. Tectonophysics, 429 (1-2), p. 209€“224. U.S. Geological Survey and California Geological Survey, 2010, Quaternary fault and fold database for the United States, accessed April 5, 2012, from USGS website: http://earthquake.usgs.gov/hazards/qfaults/.; abstract: This part of DS 781 presents data for folds for the geologic and geomorphic map of the Offshore of Pacifica map area, California. The vector data file is included in "Folds_OffshorePacifica.zip," which is accessible from http://pubs.usgs.gov/ds/781/OffshorePacifica/data_catalog_OffshorePacifica.html. The Offshore of Pacifica map area straddles the right-lateral transform boundary between the North American and Pacific plates and is cut by several active faults that cumulatively form a distributed shear zone, including the San Andreas Fault, the eastern strand of the San Gregorio Fault, the Golden Gate Fault, and the Potato Patch Fault (sheets 8, 9; Bruns and others, 2002; Ryan and others, 2008). These faults are covered by Holocene sediments (mostly units Qms, Qmsb, Qmst) with no seafloor expression, and are mapped using seismic-reflection data (sheet 8). The San Andreas Fault is the primary plate-boundary structure and extends northwest across the map area; it intersects the shoreline 10 km north of the map area at Pacifica Lagoon, and 3 km south of the map area at Mussel Rock. This section of the San Andreas Fault has an estimated slip rate of 17 to 24 mm/yr (U.S. Geological Survey, 2010), and the devastating Great 1906 California earthquake (M 7.8) is thought to have nucleated on the San Andreas a few kilometers offshore of San Francisco within the map area (sheet 9; Bolt, 1968; Lomax, 2005). The San Andreas Fault forms the boundary between two distinct basement terranes, Upper Jurassic to Lower Cretaceous rocks of the Franciscan Complex to the east, and Late Cretaceous granitic and older metamorphic rocks of the Salinian block to the west. Franciscan Complex rocks (unit KJf, undivided) form seafloor outcrops at and north of Point Lobos adjacent to onland exposures. The Franciscan is divided into 13 different units for the onshore portion of this geologic map based on different lithologies and ages, but the unit cannot be similarly divided in the offshore because of a lack of direct observation and (or) sampling. Folds were primarily mapped by interpretation of seismic reflection profile data (see S-15-10-NC and F-2-07-NC). The seismic reflection profiles were collected between 2007 and 2010. References Cited Bolt, B.A., 1968, The focus of the 1906 California earthquake: Bulletin of the Seismological Society of America, v. 58, p. 457€“471. Bruns, T.R., Cooper, A.K., Carlson, P.R., and McCulloch, D.S., 2002, Structure of the submerged San Andreas and San Gregorio fault zones in the Gulf of Farallones as inferred from high-resolution seismic-reflection data, in Parsons, T. (ed.), Crustal structure of the coastal and marine San Francisco Bay region, California: U.S. Geological Survey Professional Paper 1658, p. 77€“117. Lomax, A., 2005, A reanalysis of the hypocentral location and related observations for the Great 1906 California earthquake: Bulletin of the Seismological Society of America, v. 95, p. 861€“877. Ryan, H.F., Parsons, T., and Sliter, R.W., 2008. Vertical tectonic deformation associated with the San Andreas fault zone offshore of San Francisco, California. Tectonophysics, 429 (1-2), p. 209€“224. U.S. Geological Survey and California Geological Survey, 2010, Quaternary fault and fold database for the United States, accessed April 5, 2012, from USGS website: http://earthquake.usgs.gov/hazards/qfaults/.