Samuel Y Johnson
Seafloor Mapping - Geologic framework, hazards, and habitats
Sam Johnson is a Research Geologist in the U.S. Geological Survey Pacific Coastal and Marine Science Center (PCMSC), an organization of about 100 research and support staff based in Santa Cruz and Menlo Park, CA. He served as PCMSC Center Director from 2003 to 2008. He currently designs, coordinates, and conducts research projects that focus on seafloor and benthic habitat mapping, coastal and marine geomorphology and geologic framework, coastal evolution, and coastal earthquake and tsunami hazards. He helped plan and is the USGS lead for the multi-agency California Seafloor Mapping Program. His present research is focused on active tectonics and hazards offshore central California (Santa Barbara Channel to Cape Mendocino).
Professional Experience
1982-1984 - Assistant Professor, Washington State University
1984 to 2003 - Research Geologist, USGS Energy and Earthquake Hazards Programs
2003 to 2008 - Center Director, USGS Pacific Coastal and Marine Science Center
2008 to 2019 - Research Geologist, USGS Pacific Coastal and Marine Science Center
2019 to present - Research Geologist Emeritus, USGS Pacific Coastal and Marine Science Center
Education and Certifications
B.A. (1975) University of California, Santa Cruz (Earth Sciences)
M.S. (1978) University of Washington (Geological Sciences)
Ph.D. (1982) University of Washington Geological Sciences
Affiliations and Memberships*
Geological Society of America (Fellow)
American Geophysical Union
Society for Sedimentary Geology
Seismological Society of America
Honors and Awards
Department of Interior Distinguished Service Award (2019)
Science and Products
Filter Total Items: 19
California State Waters Map Series Data Catalog--Point Sur to Point Arguello California State Waters Map Series Data Catalog--Point Sur to Point Arguello
As part of the USGS's California State Waters Mapping Project, a 50-m grid of sediment thickness for the seafloor within the 3-nautical mile limit between Point Sur and Point Arguello was generated from seismic-reflection data collected between 2008 and 2014, and supplemented with geologic structure (fault and fold) information following the methodology of Wong (2012). Water depths...
Multichannel minisparker seismic-reflection data of field activity 2015-617-FA; Monterey Bay, offshore central California from 2015-02-23 to 2015-03-06 Multichannel minisparker seismic-reflection data of field activity 2015-617-FA; Monterey Bay, offshore central California from 2015-02-23 to 2015-03-06
This data release contains approximately 190 line-kilometers of processed, high-resolution multichannel seismic-reflection (MCS) profiles that were collected aboard the R/V Snavely in 2015 on U.S. Geological Survey cruise 2015-617-FA in Monterey Bay, offshore central California. The majority of MCS profiles collected are oriented north-south across the Monterey Canyon head to address...
Marine magnetic data from Point Sur to Piedras Blancas, central California, 2011 Marine magnetic data from Point Sur to Piedras Blancas, central California, 2011
This dataset includes marine magnetic data collected by the U.S. Geological Survey (USGS) in 2011 during field activity B-05-11-CC between Point Sur and Piedras Blancas, central California.
Minisparker seismic-reflection data collected between Point Sur and Morro Bay, offshore of central California, from 2011-09-12 to 2011-09-26 (USGS field activity B-05-11-CC) Minisparker seismic-reflection data collected between Point Sur and Morro Bay, offshore of central California, from 2011-09-12 to 2011-09-26 (USGS field activity B-05-11-CC)
This data release includes marine geophysical data collected on cruise B-05-11-CC between Point Sur and Morro Bay, California. The overall goal of this research is to understand the shallow geologic framework of this area as a contribution to the California Seafloor Mapping Program (Johnson and others, 2017). Particular focus is on mapping active faults and documenting the distribution...
Marine geophysical data - Point Sal to Refugio State Beach, southern California Marine geophysical data - Point Sal to Refugio State Beach, southern California
This data release includes approximately 1,032 km of marine single-channel seismic-reflection data collected by the U.S. Geological Survey on a research cruise (USGS survey 2014-632-FA) in July and August, 2014, between Point Sal and Refugio State Beach. The dataset includes 168 profiles, most of which were collected on tracklines roughly perpendicular to the coast at 1 km line spacing...
Marine Geophysical Data -- Point Arena to Cape Mendocino Marine Geophysical Data -- Point Arena to Cape Mendocino
This data release includes marine geophysical data collected on three research cruises conducted in 2010 and 2012 between Point Arena and Cape Mendocino. The overall goal of this research is to better understand the northernmost section of the San Andreas Fault (SAF). In 2010, the USGS collected seismic-reflection profiles crossing the SAF at 1 km spacing from Point Arena to Fort Bragg...
California State Waters Map Series: Offshore of Carpinteria, California California State Waters Map Series: Offshore of Carpinteria, California
In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration...
California State Waters Map Series — Offshore of Ventura, California California State Waters Map Series — Offshore of Ventura, California
In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration...
California State Waters Map Series: Offshore of Santa Barbara, California California State Waters Map Series: Offshore of Santa Barbara, California
In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration...
California State Waters Map Series — Hueneme Canyon and vicinity, California California State Waters Map Series — Hueneme Canyon and vicinity, California
In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California's State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration...
Filter Total Items: 65
Offshore shallow structure and sediment distribution, Punta Gorda to Point Arena, Northern California Offshore shallow structure and sediment distribution, Punta Gorda to Point Arena, Northern California
This publication consists of two map sheets that display shallow geologic structure, along with sediment distribution and thickness, for an approximately 150-km-long offshore section of the northern California coast between Punta Gorda and Point Arena. Each map sheet includes three maps at scales of either 1:100,000 or 1:200,000, and together the sheets include 30 figures that contain
Authors
Jeffrey Beeson, Samuel Y. Johnson
Offshore shallow structure and sediment distribution, Point Sur to Point Arguello, central California Offshore shallow structure and sediment distribution, Point Sur to Point Arguello, central California
This publication consists of three map sheets that display shallow geologic structure, along with sediment distribution and thickness, for an about 225-km-long offshore section of the central California coast between Point Sur and Point Arguello. Each map sheet includes three maps, at scales of either 1:150,000 or 1:200,000, as well as a set of figures that contain representative high...
Authors
Samuel Y. Johnson, Stephen R. Hartwell, Janet T. Watt, Jeffrey Beeson, Peter Dartnell
Shallow structure and geomorphology along the offshore northern San Andreas Fault, Tomales Point to Fort Ross, California Shallow structure and geomorphology along the offshore northern San Andreas Fault, Tomales Point to Fort Ross, California
We mapped a poorly documented 35-km-long section of the northern San Andreas fault zone (NSAF) between Tomales Point and Fort Ross, California. Mapping is largely based on high-resolution seismic-reflection profiles (38 fault crossings), multibeam bathymetry, and onshore geology. NSAF strike in this section is nearly parallel to plate motion, characterized by a slight (~2°) northerly
Authors
Samuel Johnson, Beeson Jeffrey W.
Controls on submarine canyon head evolution: Monterey Canyon, offshore central California Controls on submarine canyon head evolution: Monterey Canyon, offshore central California
The Monterey submarine canyon, incised across the continental shelf in Monterey Bay, California, provides a record of the link between onshore tectonism, fluvial transport, and deep-marine deposition. High-resolution seismic-reflection imaging in Monterey Bay reveals an extensive paleocanyon unit buried below the seafloor of the continental shelf around Monterey and Soquel canyon heads
Authors
Katherine Maier, Samuel Johnson, Patrick Hart
Neotectonics of the Big Sur Bend, San Gregorio‐Hosgri fault system, central California Neotectonics of the Big Sur Bend, San Gregorio‐Hosgri fault system, central California
The right‐lateral San Gregorio‐Hosgri fault system (SGHF) extends mainly offshore for about 400 km along the central California coast and is a major structure in the distributed transform margin of western North America. We mapped a poorly known 64‐km‐long section of the SGHF offshore Big Sur between Piedras Blancas and Point Sur using high‐resolution bathymetry, seismic reflection, and...
Authors
Samuel Johnson, Janet Watt, Stephen Hartwell, Jared Kluesner
California State Waters Map Series — Offshore of Point Conception, California California State Waters Map Series — Offshore of Point Conception, California
Introduction In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection...
Authors
Samuel Johnson, Peter Dartnell, Guy Cochrane, Stephen Hartwell, Nadine Golden, Rikk Kvitek, Clifton Davenport
Science and Products
Filter Total Items: 19
California State Waters Map Series Data Catalog--Point Sur to Point Arguello California State Waters Map Series Data Catalog--Point Sur to Point Arguello
As part of the USGS's California State Waters Mapping Project, a 50-m grid of sediment thickness for the seafloor within the 3-nautical mile limit between Point Sur and Point Arguello was generated from seismic-reflection data collected between 2008 and 2014, and supplemented with geologic structure (fault and fold) information following the methodology of Wong (2012). Water depths...
Multichannel minisparker seismic-reflection data of field activity 2015-617-FA; Monterey Bay, offshore central California from 2015-02-23 to 2015-03-06 Multichannel minisparker seismic-reflection data of field activity 2015-617-FA; Monterey Bay, offshore central California from 2015-02-23 to 2015-03-06
This data release contains approximately 190 line-kilometers of processed, high-resolution multichannel seismic-reflection (MCS) profiles that were collected aboard the R/V Snavely in 2015 on U.S. Geological Survey cruise 2015-617-FA in Monterey Bay, offshore central California. The majority of MCS profiles collected are oriented north-south across the Monterey Canyon head to address...
Marine magnetic data from Point Sur to Piedras Blancas, central California, 2011 Marine magnetic data from Point Sur to Piedras Blancas, central California, 2011
This dataset includes marine magnetic data collected by the U.S. Geological Survey (USGS) in 2011 during field activity B-05-11-CC between Point Sur and Piedras Blancas, central California.
Minisparker seismic-reflection data collected between Point Sur and Morro Bay, offshore of central California, from 2011-09-12 to 2011-09-26 (USGS field activity B-05-11-CC) Minisparker seismic-reflection data collected between Point Sur and Morro Bay, offshore of central California, from 2011-09-12 to 2011-09-26 (USGS field activity B-05-11-CC)
This data release includes marine geophysical data collected on cruise B-05-11-CC between Point Sur and Morro Bay, California. The overall goal of this research is to understand the shallow geologic framework of this area as a contribution to the California Seafloor Mapping Program (Johnson and others, 2017). Particular focus is on mapping active faults and documenting the distribution...
Marine geophysical data - Point Sal to Refugio State Beach, southern California Marine geophysical data - Point Sal to Refugio State Beach, southern California
This data release includes approximately 1,032 km of marine single-channel seismic-reflection data collected by the U.S. Geological Survey on a research cruise (USGS survey 2014-632-FA) in July and August, 2014, between Point Sal and Refugio State Beach. The dataset includes 168 profiles, most of which were collected on tracklines roughly perpendicular to the coast at 1 km line spacing...
Marine Geophysical Data -- Point Arena to Cape Mendocino Marine Geophysical Data -- Point Arena to Cape Mendocino
This data release includes marine geophysical data collected on three research cruises conducted in 2010 and 2012 between Point Arena and Cape Mendocino. The overall goal of this research is to better understand the northernmost section of the San Andreas Fault (SAF). In 2010, the USGS collected seismic-reflection profiles crossing the SAF at 1 km spacing from Point Arena to Fort Bragg...
California State Waters Map Series: Offshore of Carpinteria, California California State Waters Map Series: Offshore of Carpinteria, California
In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration...
California State Waters Map Series — Offshore of Ventura, California California State Waters Map Series — Offshore of Ventura, California
In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration...
California State Waters Map Series: Offshore of Santa Barbara, California California State Waters Map Series: Offshore of Santa Barbara, California
In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration...
California State Waters Map Series — Hueneme Canyon and vicinity, California California State Waters Map Series — Hueneme Canyon and vicinity, California
In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California's State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration...
Filter Total Items: 65
Offshore shallow structure and sediment distribution, Punta Gorda to Point Arena, Northern California Offshore shallow structure and sediment distribution, Punta Gorda to Point Arena, Northern California
This publication consists of two map sheets that display shallow geologic structure, along with sediment distribution and thickness, for an approximately 150-km-long offshore section of the northern California coast between Punta Gorda and Point Arena. Each map sheet includes three maps at scales of either 1:100,000 or 1:200,000, and together the sheets include 30 figures that contain
Authors
Jeffrey Beeson, Samuel Y. Johnson
Offshore shallow structure and sediment distribution, Point Sur to Point Arguello, central California Offshore shallow structure and sediment distribution, Point Sur to Point Arguello, central California
This publication consists of three map sheets that display shallow geologic structure, along with sediment distribution and thickness, for an about 225-km-long offshore section of the central California coast between Point Sur and Point Arguello. Each map sheet includes three maps, at scales of either 1:150,000 or 1:200,000, as well as a set of figures that contain representative high...
Authors
Samuel Y. Johnson, Stephen R. Hartwell, Janet T. Watt, Jeffrey Beeson, Peter Dartnell
Shallow structure and geomorphology along the offshore northern San Andreas Fault, Tomales Point to Fort Ross, California Shallow structure and geomorphology along the offshore northern San Andreas Fault, Tomales Point to Fort Ross, California
We mapped a poorly documented 35-km-long section of the northern San Andreas fault zone (NSAF) between Tomales Point and Fort Ross, California. Mapping is largely based on high-resolution seismic-reflection profiles (38 fault crossings), multibeam bathymetry, and onshore geology. NSAF strike in this section is nearly parallel to plate motion, characterized by a slight (~2°) northerly
Authors
Samuel Johnson, Beeson Jeffrey W.
Controls on submarine canyon head evolution: Monterey Canyon, offshore central California Controls on submarine canyon head evolution: Monterey Canyon, offshore central California
The Monterey submarine canyon, incised across the continental shelf in Monterey Bay, California, provides a record of the link between onshore tectonism, fluvial transport, and deep-marine deposition. High-resolution seismic-reflection imaging in Monterey Bay reveals an extensive paleocanyon unit buried below the seafloor of the continental shelf around Monterey and Soquel canyon heads
Authors
Katherine Maier, Samuel Johnson, Patrick Hart
Neotectonics of the Big Sur Bend, San Gregorio‐Hosgri fault system, central California Neotectonics of the Big Sur Bend, San Gregorio‐Hosgri fault system, central California
The right‐lateral San Gregorio‐Hosgri fault system (SGHF) extends mainly offshore for about 400 km along the central California coast and is a major structure in the distributed transform margin of western North America. We mapped a poorly known 64‐km‐long section of the SGHF offshore Big Sur between Piedras Blancas and Point Sur using high‐resolution bathymetry, seismic reflection, and...
Authors
Samuel Johnson, Janet Watt, Stephen Hartwell, Jared Kluesner
California State Waters Map Series — Offshore of Point Conception, California California State Waters Map Series — Offshore of Point Conception, California
Introduction In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection...
Authors
Samuel Johnson, Peter Dartnell, Guy Cochrane, Stephen Hartwell, Nadine Golden, Rikk Kvitek, Clifton Davenport
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government