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
No Result Found
Filter Total Items: 65
Map and data for Quaternary faults and folds in Washington state Map and data for Quaternary faults and folds in Washington state
The map shows faults and folds in Washington State that exhibit evidence of Quaternary deformation and includes data on timing of most recent movement, sense of movement, slip rate, and continuity of surface expression.
Authors
David Lidke, Samuel Johnson, Patricia McCrory, Stephen Personius, Alan Nelson, Richard Dart, Lee-Ann Bradley, Kathleen M. Haller, Michael N. Machette
Evidence for Late Holocene earthquakes on the Utsalady Point fault, Northern Puget Lowland, Washington Evidence for Late Holocene earthquakes on the Utsalady Point fault, Northern Puget Lowland, Washington
Trenches across the Utsalady Point fault in the northern Puget Lowland of Washington reveal evidence of at least one and probably two late Holocene earthquakes. The "Teeka" and "Duffers" trenches were located along a 1.4-km-long, 1-to 4-m-high, northwest-trending, southwest-facing, topographic scarp recognized from Airborne Laser Swath Mapping. Glaciomarine drift exposed in the trenches...
Authors
S. Johnson, A.R. Nelson, S. F. Personius, R.E. Wells, H.M. Kelsey, B.L. Sherrod, K. Okumura, R. Koehler, Robert C. Witter, L. Bradley, D.J. Harding
Active shortening of the Cascadia forearc and implications for seismic hazards of the Puget Lowland Active shortening of the Cascadia forearc and implications for seismic hazards of the Puget Lowland
Margin-parallel shortening of the Cascadia forearc is a consequence of oblique subduction of the Juan de Fuca plate beneath North America. Strike-slip, thrust, and oblique crustal faults beneath the densely populated Puget Lowland accommodate much of this north-south compression, resulting in large crustal earthquakes. To better understand this forearc deformation and improve earthquake...
Authors
S. Johnson, R.J. Blakely, W. Stephenson, S. Dadisman, M. Fisher
Late Holocene earthquakes on the Toe Jam Hill fault, Seattle fault zone, Bainbridge Island, Washington Late Holocene earthquakes on the Toe Jam Hill fault, Seattle fault zone, Bainbridge Island, Washington
Five trenches across a Holocene fault scarp yield the first radiocarbon-measured earthquake recurrence intervals for a crustal fault in western Washington. The scarp, the first to be revealed by laser imagery, marks the Toe Jam Hill fault, a north-dipping backthrust to the Seattle fault. Folded and faulted strata, liquefaction features, and forest soil A horizons buried by hanging-wall...
Authors
A.R. Nelson, S. Johnson, H.M. Kelsey, R.E. Wells, B.L. Sherrod, S.K. Pezzopane, L. Bradley, R. Koehler, R.C. Bucknam
Hydrothermal and tectonic activity in northern Yellowstone Lake, Wyoming Hydrothermal and tectonic activity in northern Yellowstone Lake, Wyoming
Yellowstone National Park is the site of one of the world's largest calderas. The abundance of geothermal and tectonic activity in and around the caldera, including historic uplift and subsidence, makes it necessary to understand active geologic processes and their associated hazards. To that end, we here use an extensive grid of high-resolution seismic reflection profiles (∼450 km) to...
Authors
S. Johnson, W. Stephenson, L. Morgan, Wayne C. Shanks, K. Pierce
Field and laboratory data from an earthquake history study of the Toe Jam Hill Fault, Bainbridge Island, Washington Field and laboratory data from an earthquake history study of the Toe Jam Hill Fault, Bainbridge Island, Washington
No abstract available.
Authors
Alan Nelson, Samuel Johnson, Ray E. Wells, Silvio Pezzopane, Harvey Kelsey, Brian Sherrod, Lee-Ann Bradley, Rick Koehler, Robert Bucknam, Ralph Haugerud, William Laprade
Science and Products
Filter Total Items: 19
No Result Found
Filter Total Items: 65
Map and data for Quaternary faults and folds in Washington state Map and data for Quaternary faults and folds in Washington state
The map shows faults and folds in Washington State that exhibit evidence of Quaternary deformation and includes data on timing of most recent movement, sense of movement, slip rate, and continuity of surface expression.
Authors
David Lidke, Samuel Johnson, Patricia McCrory, Stephen Personius, Alan Nelson, Richard Dart, Lee-Ann Bradley, Kathleen M. Haller, Michael N. Machette
Evidence for Late Holocene earthquakes on the Utsalady Point fault, Northern Puget Lowland, Washington Evidence for Late Holocene earthquakes on the Utsalady Point fault, Northern Puget Lowland, Washington
Trenches across the Utsalady Point fault in the northern Puget Lowland of Washington reveal evidence of at least one and probably two late Holocene earthquakes. The "Teeka" and "Duffers" trenches were located along a 1.4-km-long, 1-to 4-m-high, northwest-trending, southwest-facing, topographic scarp recognized from Airborne Laser Swath Mapping. Glaciomarine drift exposed in the trenches...
Authors
S. Johnson, A.R. Nelson, S. F. Personius, R.E. Wells, H.M. Kelsey, B.L. Sherrod, K. Okumura, R. Koehler, Robert C. Witter, L. Bradley, D.J. Harding
Active shortening of the Cascadia forearc and implications for seismic hazards of the Puget Lowland Active shortening of the Cascadia forearc and implications for seismic hazards of the Puget Lowland
Margin-parallel shortening of the Cascadia forearc is a consequence of oblique subduction of the Juan de Fuca plate beneath North America. Strike-slip, thrust, and oblique crustal faults beneath the densely populated Puget Lowland accommodate much of this north-south compression, resulting in large crustal earthquakes. To better understand this forearc deformation and improve earthquake...
Authors
S. Johnson, R.J. Blakely, W. Stephenson, S. Dadisman, M. Fisher
Late Holocene earthquakes on the Toe Jam Hill fault, Seattle fault zone, Bainbridge Island, Washington Late Holocene earthquakes on the Toe Jam Hill fault, Seattle fault zone, Bainbridge Island, Washington
Five trenches across a Holocene fault scarp yield the first radiocarbon-measured earthquake recurrence intervals for a crustal fault in western Washington. The scarp, the first to be revealed by laser imagery, marks the Toe Jam Hill fault, a north-dipping backthrust to the Seattle fault. Folded and faulted strata, liquefaction features, and forest soil A horizons buried by hanging-wall...
Authors
A.R. Nelson, S. Johnson, H.M. Kelsey, R.E. Wells, B.L. Sherrod, S.K. Pezzopane, L. Bradley, R. Koehler, R.C. Bucknam
Hydrothermal and tectonic activity in northern Yellowstone Lake, Wyoming Hydrothermal and tectonic activity in northern Yellowstone Lake, Wyoming
Yellowstone National Park is the site of one of the world's largest calderas. The abundance of geothermal and tectonic activity in and around the caldera, including historic uplift and subsidence, makes it necessary to understand active geologic processes and their associated hazards. To that end, we here use an extensive grid of high-resolution seismic reflection profiles (∼450 km) to...
Authors
S. Johnson, W. Stephenson, L. Morgan, Wayne C. Shanks, K. Pierce
Field and laboratory data from an earthquake history study of the Toe Jam Hill Fault, Bainbridge Island, Washington Field and laboratory data from an earthquake history study of the Toe Jam Hill Fault, Bainbridge Island, Washington
No abstract available.
Authors
Alan Nelson, Samuel Johnson, Ray E. Wells, Silvio Pezzopane, Harvey Kelsey, Brian Sherrod, Lee-Ann Bradley, Rick Koehler, Robert Bucknam, Ralph Haugerud, William Laprade
*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