John Barron, Ph.D.
John is a Scientist Emeritus with the Geology, Minerals, Energy, and Geophysics Science center in Menlo Park, CA.
John is a marine micropaleontologist (diatoms) with expertise in and biostratigraphy and paleoceanography. His biostratigraphic expertise extends from the Late Cretaceous to the Holocene, with an emphasis on the North Pacific, eastern equatorial Pacific, and Southern Ocean. John's paleoclimate expertise is mostly on the Holocene of the North Pacific, ranging from the Gulf of California to the Gulf of Alaska. As an Emeritus Research Geologist, his research is directed toward developing and comparing Holocene sea surface temperature records in these eastern North Pacific regions with hydroclimate records in western North America and suggesting links.
Professional Experience
2012- 2016 (June) - Project Chief, Pacific Ocean Climate Variability: Effects on North American Precipitation Patterns Project, Climate and Land Use Change, Research & Development Program
1995-1997 – Project Chief: Pliocene, Research, Interpretation, and Synoptic Mapping(PRISM), Global Change & Climate History Program, Volcano Hazards Team, Menlo Park
1984-1995 – Project Chief and micropaleontologist of various USGS biochronology projects providing support to USGS mapping projects, Paleontology & Stratigraphy Branch
1974-1983 –Micropaleontolgist (diatoms), Paleontology & Stratigraphy Branch
Scientific Cruise Experience
Deep Sea Drilling Project (Leg 57-Japan; 63 (California margin; 85 (eastern equatorial Pacific); micropaleontologist
Ocean Drilling Project 119 (Antarctic margin, Indian Ocean; Co-Chief Scientist), 145 (North Pacific transect, micropaleotologist).
Education and Certifications
1969 BS (Geology), University of California, Los Angeles
1974 PhD (Geology), University of California, Los Angeles
Honors and Awards
2011 - The Brady Medal of the Micropalaeological Society (UK)
1994 - U.S. Dept. of Interior Meritorious Service Award
1986 - Charles Schuchert Award - from the Paleontological Society for excellence and promise in paleontology for scientists under 40 years old
Science and Products
Pacific Ocean Patterns, Processes, and Productivity (POP3): Impacts of ancient warming on marine ecosystems and western North America
Projections for AD 2100 suggest warming of +1-4°C in the North Pacific Ocean, which will result in widespread transformations throughout the marine environment and western North America. Many of these changes are beyond the predictive capabilities of current climate models. To better address this future uncertainty, our team is developing a geological framework using past warm intervals as...
Diatom Samples from Ocean Drilling Program Leg 112, Holes 682A and 688E from Offshore Peru Diatom Samples from Ocean Drilling Program Leg 112, Holes 682A and 688E from Offshore Peru
The diatom biochronology of ODP Holes 682A and 688E provides a nearly complete offshore reference section to correspond with onshore studies of the Miocene age materials of the East Pisco Basin of Southern Peru, which is known for its excellent preservation of fossil vertebrates. From these holes a nearly complete sequence of low latitude and northeastern Pacific diatoms has been...
Microfossil Samples from the East Pisco Basin, southern Peru Microfossil Samples from the East Pisco Basin, southern Peru
The East Pisco Basin is one of several forearc basins situated on the coastal plain of Peru between the Andean Cordillera and Peru-Chile Trench. During the Cenozoic, successive marine transgressions across the East Pisco Basin deposited sequences of Paleogene and Neogene age. Biochronologic studies suggest that a hiatus of approximately 12 million years (~32-20 Ma) separates the youngest...
Filter Total Items: 116
Chronology and Paleoenvironment of the Tunga Formation, a new lowermost Miocene sequence in the East Pisco Basin of southern Peru Chronology and Paleoenvironment of the Tunga Formation, a new lowermost Miocene sequence in the East Pisco Basin of southern Peru
The East Pisco Basin, occupying the coastal plain of Peru between 13°S and 16°S, is widely known for its extensive Eocene to Quaternary biosiliceous deposits and excellent preservation of fossil marine vertebrates. Biochronologic studies published over the past 35 years record a hiatus of about 13 million years (*32–19 Ma) separating the youngest Paleogene deposits (Otuma Formation) from...
Authors
Thomas J. Devries, John A. Barron, Diana Ochoa, Kristen McDougall
Ibex Hollow Tuff from ca. 12 Ma supereruption, southern Idaho, identified across North America, eastern Pacific Ocean, and Gulf of Mexico Ibex Hollow Tuff from ca. 12 Ma supereruption, southern Idaho, identified across North America, eastern Pacific Ocean, and Gulf of Mexico
The Ibex Hollow Tuff, 12.08 ± 0.03 Ma (40Ar/39Ar), is a widespread tephra layer erupted from the Bruneau-Jarbidge volcanic field of southern Idaho. Tephra from this eruption was deposited across much of western and central North America and adjacent ocean areas. We identified the Ibex Hollow Tuff at Trapper Creek, Idaho, near its eruption site, and at 15 distal sites, from the Pacific...
Authors
Andrei M. Sarna-Wojcicki, Jeffrey R. Knott, John A. Westgate, James R. Budahn, John A. Barron, Colin J. Bray, Greg A. Ludvigson, Charles E. Meyer, David M. Miller, Rick E. Otto, Nicholas J.G. Pearce, Charles C. Smith, Laura Walkup, Elmira Wan, James Yount
Tephrochronology of the Miocene Monterey and Modelo Formations, California Tephrochronology of the Miocene Monterey and Modelo Formations, California
Tuff beds have been known in the Miocene Monterey and Modelo Formations since the initial descriptions; however, age control and correlation is predominantly biostratigraphy. Here we combine tephrochronology and biostratigraphy in order to provide numerical age control for eight sedimentary sequences of the Monterey and Modelo Formations from Monterey, California to Orange County...
Authors
Jeffrey R. Knott, Andrei M. Sarna-Wojcicki, John A. Barron, Elmira Wan, Nancy Heizler, Priscilla Martinez
Miocene terrestrial paleoclimates inferred from pollen in the Monterey Formation, Naples Coastal Bluffs section, California Miocene terrestrial paleoclimates inferred from pollen in the Monterey Formation, Naples Coastal Bluffs section, California
We present here a comprehensive record of Miocene terrestrial ecosystems from exposures of the Monterey Formation along the Naples coastal bluffs, west of Santa Barbara, California. Constrained by an updated chronology, pollen analyses of 28 samples deposited between 18 and 6 Ma reflect the demise of mesophytic taxa that grew in a warm, wet environment during the late early and early...
Authors
Linda E. Heusser, John A. Barron, Gregg Blake, Jon Nichols
A refined assessment of the paleoceanographic and tectonic influences on the deposition of the Monterey Formation in California A refined assessment of the paleoceanographic and tectonic influences on the deposition of the Monterey Formation in California
Application of updated diatom biochronology to the Monterey Formation and related biosiliceous rocks reveals the imprint of both global paleoclimatic/ paleoceanographic and regional tectonic events. A rise in global sea level combined with regional tectonic deepening associated with the development of the transform California margin resulted in the abrupt onset of deposition of fine...
Authors
John A. Barron
Middle and late Miocene marine mammal assemblages from the Monterey Formation of Orange County, California Middle and late Miocene marine mammal assemblages from the Monterey Formation of Orange County, California
This study provides new stratigraphic data and identifications for fossil marine mammals from the Monterey Formation in the Capistrano syncline, Orange County, California, showing that there are two distinct marine mammal assemblages. Until now, marine mammals from the Monterey Formation of Orange County have been considered to represent a single assemblage that is 13.0–10.0 Ma in age...
Authors
James F. Parham, John A. Barron, Jorge Velez-Juarbe
An 11,300 yr record of paleoclimatology and paleoceanography of the central California coast in a gravity core from Pioneer Seamount An 11,300 yr record of paleoclimatology and paleoceanography of the central California coast in a gravity core from Pioneer Seamount
Diatom, pollen, silicoflagellate, and biogenic opal analyses from a 155 cm-long gravity core from Pioneer Seamount, offshore Santa Cruz, California (PS1410-06 GC, latitude 37.3°N, longitude 123.4°W, water depth 2165 m) are compiled for the last ~11,300 years and compared with those of ODP 1019 and TN062-O550 from northern California. The relative abundance record of the subtropical...
Authors
John A. Barron, Jason A. Addison, Linda E. Heusser, David Bukry, Valerie Evelyn Schwartz, Amy Wagner
The Miocene stratigraphy of the Laberinto area (Río Ica Valley) and its bearing on the geological history of the East Pisco Basin (south-central Peru) The Miocene stratigraphy of the Laberinto area (Río Ica Valley) and its bearing on the geological history of the East Pisco Basin (south-central Peru)
Global sea-level changes and substantial vertical displacement along the Monte Grande Fault (MGF) in the lower Río Ica Valley of south-central Peru influenced the accumulation of bioclast-bearing and diatom-bearing Miocene siliciclastic sediments in an area of the East Pisco forearc basin (EPB) colloquially known as Laberinto. Two depositional hiatuses in the Laberinto area (∼17–14 Ma,...
Authors
Thomas J. Devries, John A. Barron, Mario Urbina-Schmitt, Diana Ochoa, Raúl Esperante, Lawrence W. Snee
A North American Hydroclimate Synthesis (NAHS) of the Common Era A North American Hydroclimate Synthesis (NAHS) of the Common Era
This study presents a synthesis of century-scale hydroclimate variations in North America for the Common Era (last 2000 years) using new age models of previously published multiple proxy-based paleoclimate data. This North American Hydroclimate Synthesis (NAHS) examines regional hydroclimate patterns and related environmental indicators, including vegetation, lake water elevation, stream...
Authors
Jessica R. Rodysill, Lesleigh Anderson, Thomas M. Cronin, Miriam C. Jones, Robert S. Thompson, David B. Wahl, Debra A. Willard, Jason A. Addison, Jay R. Alder, Katherine H. Anderson, Lysanna Anderson, John A. Barron, Christopher E. Bernhardt, Steven W. Hostetler, Natalie M. Kehrwald, Nicole Khan, Julie N. Richey, Scott W. Starratt, Laura E. Strickland, Michael Toomey, Claire C. Treat, G. Lynn Wingard
By
Water Resources Mission Area, Ecosystems Land Change Science Program, Energy Resources Program, Groundwater and Streamflow Information Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Florence Bascom Geoscience Center, Geology, Minerals, Energy, and Geophysics Science Center, Geosciences and Environmental Change Science Center, St. Petersburg Coastal and Marine Science Center
Evaluation of hypotheses for right-lateral displacement of Neogene strata along the San Andreas Fault between Parkfield and Maricopa, California Evaluation of hypotheses for right-lateral displacement of Neogene strata along the San Andreas Fault between Parkfield and Maricopa, California
We used geological field studies and diatom biostratigraphy to test a published hypothesis that Neogene marine siliceous strata in the Maricopa and Parkfield areas, located on opposite sides of the San Andreas Fault, were formerly contiguous and then were displaced by about 80–130 kilometers (km) of right-lateral slip along the fault. In the Maricopa area on the northeast side of the San...
Authors
Richard G. Stanley, John A. Barron, Charles L. Powell
A Holocene record of ocean productivity and upwelling from the northern California continental slope A Holocene record of ocean productivity and upwelling from the northern California continental slope
The Holocene upwelling history of the northern California continental slope is examined using the high-resolution record of TN062-O550 (40.9°N, 124.6°W, 550 m water depth). This 7-m-long marine sediment core spans the last ∼7500 years, and we use it to test the hypothesis that marine productivity in the California Current System (CCS) driven by coastal upwelling has co-varied with...
Authors
Jason A. Addison, John A. Barron, Bruce P. Finney, Jennifer E. Kusler, David Bukry, Linda E. Heusser, Clark R. Alexander
High-resolution climate of the past ∼7300 years of coastal northernmost California: Results from diatoms, silicoflagellates, and pollen High-resolution climate of the past ∼7300 years of coastal northernmost California: Results from diatoms, silicoflagellates, and pollen
Piston core TN062-O550, collected about 33 km offshore of Eureka, California, contains a high-resolution record of the climate and oceanography of coastal northernmost California during the past ∼7.34 kyr. Chronology established by nine AMS ages on a combination of planktic foraminifers, bivalve shell fragments, and wood yields a mean sedimentation rate of 103 cm kyr−1. Marine proxies...
Authors
John A. Barron, David Bukry, Linda E. Heusser, Jason A. Addison, Clark R. Alexander
Science and Products
Pacific Ocean Patterns, Processes, and Productivity (POP3): Impacts of ancient warming on marine ecosystems and western North America
Projections for AD 2100 suggest warming of +1-4°C in the North Pacific Ocean, which will result in widespread transformations throughout the marine environment and western North America. Many of these changes are beyond the predictive capabilities of current climate models. To better address this future uncertainty, our team is developing a geological framework using past warm intervals as...
Diatom Samples from Ocean Drilling Program Leg 112, Holes 682A and 688E from Offshore Peru Diatom Samples from Ocean Drilling Program Leg 112, Holes 682A and 688E from Offshore Peru
The diatom biochronology of ODP Holes 682A and 688E provides a nearly complete offshore reference section to correspond with onshore studies of the Miocene age materials of the East Pisco Basin of Southern Peru, which is known for its excellent preservation of fossil vertebrates. From these holes a nearly complete sequence of low latitude and northeastern Pacific diatoms has been...
Microfossil Samples from the East Pisco Basin, southern Peru Microfossil Samples from the East Pisco Basin, southern Peru
The East Pisco Basin is one of several forearc basins situated on the coastal plain of Peru between the Andean Cordillera and Peru-Chile Trench. During the Cenozoic, successive marine transgressions across the East Pisco Basin deposited sequences of Paleogene and Neogene age. Biochronologic studies suggest that a hiatus of approximately 12 million years (~32-20 Ma) separates the youngest...
Filter Total Items: 116
Chronology and Paleoenvironment of the Tunga Formation, a new lowermost Miocene sequence in the East Pisco Basin of southern Peru Chronology and Paleoenvironment of the Tunga Formation, a new lowermost Miocene sequence in the East Pisco Basin of southern Peru
The East Pisco Basin, occupying the coastal plain of Peru between 13°S and 16°S, is widely known for its extensive Eocene to Quaternary biosiliceous deposits and excellent preservation of fossil marine vertebrates. Biochronologic studies published over the past 35 years record a hiatus of about 13 million years (*32–19 Ma) separating the youngest Paleogene deposits (Otuma Formation) from...
Authors
Thomas J. Devries, John A. Barron, Diana Ochoa, Kristen McDougall
Ibex Hollow Tuff from ca. 12 Ma supereruption, southern Idaho, identified across North America, eastern Pacific Ocean, and Gulf of Mexico Ibex Hollow Tuff from ca. 12 Ma supereruption, southern Idaho, identified across North America, eastern Pacific Ocean, and Gulf of Mexico
The Ibex Hollow Tuff, 12.08 ± 0.03 Ma (40Ar/39Ar), is a widespread tephra layer erupted from the Bruneau-Jarbidge volcanic field of southern Idaho. Tephra from this eruption was deposited across much of western and central North America and adjacent ocean areas. We identified the Ibex Hollow Tuff at Trapper Creek, Idaho, near its eruption site, and at 15 distal sites, from the Pacific...
Authors
Andrei M. Sarna-Wojcicki, Jeffrey R. Knott, John A. Westgate, James R. Budahn, John A. Barron, Colin J. Bray, Greg A. Ludvigson, Charles E. Meyer, David M. Miller, Rick E. Otto, Nicholas J.G. Pearce, Charles C. Smith, Laura Walkup, Elmira Wan, James Yount
Tephrochronology of the Miocene Monterey and Modelo Formations, California Tephrochronology of the Miocene Monterey and Modelo Formations, California
Tuff beds have been known in the Miocene Monterey and Modelo Formations since the initial descriptions; however, age control and correlation is predominantly biostratigraphy. Here we combine tephrochronology and biostratigraphy in order to provide numerical age control for eight sedimentary sequences of the Monterey and Modelo Formations from Monterey, California to Orange County...
Authors
Jeffrey R. Knott, Andrei M. Sarna-Wojcicki, John A. Barron, Elmira Wan, Nancy Heizler, Priscilla Martinez
Miocene terrestrial paleoclimates inferred from pollen in the Monterey Formation, Naples Coastal Bluffs section, California Miocene terrestrial paleoclimates inferred from pollen in the Monterey Formation, Naples Coastal Bluffs section, California
We present here a comprehensive record of Miocene terrestrial ecosystems from exposures of the Monterey Formation along the Naples coastal bluffs, west of Santa Barbara, California. Constrained by an updated chronology, pollen analyses of 28 samples deposited between 18 and 6 Ma reflect the demise of mesophytic taxa that grew in a warm, wet environment during the late early and early...
Authors
Linda E. Heusser, John A. Barron, Gregg Blake, Jon Nichols
A refined assessment of the paleoceanographic and tectonic influences on the deposition of the Monterey Formation in California A refined assessment of the paleoceanographic and tectonic influences on the deposition of the Monterey Formation in California
Application of updated diatom biochronology to the Monterey Formation and related biosiliceous rocks reveals the imprint of both global paleoclimatic/ paleoceanographic and regional tectonic events. A rise in global sea level combined with regional tectonic deepening associated with the development of the transform California margin resulted in the abrupt onset of deposition of fine...
Authors
John A. Barron
Middle and late Miocene marine mammal assemblages from the Monterey Formation of Orange County, California Middle and late Miocene marine mammal assemblages from the Monterey Formation of Orange County, California
This study provides new stratigraphic data and identifications for fossil marine mammals from the Monterey Formation in the Capistrano syncline, Orange County, California, showing that there are two distinct marine mammal assemblages. Until now, marine mammals from the Monterey Formation of Orange County have been considered to represent a single assemblage that is 13.0–10.0 Ma in age...
Authors
James F. Parham, John A. Barron, Jorge Velez-Juarbe
An 11,300 yr record of paleoclimatology and paleoceanography of the central California coast in a gravity core from Pioneer Seamount An 11,300 yr record of paleoclimatology and paleoceanography of the central California coast in a gravity core from Pioneer Seamount
Diatom, pollen, silicoflagellate, and biogenic opal analyses from a 155 cm-long gravity core from Pioneer Seamount, offshore Santa Cruz, California (PS1410-06 GC, latitude 37.3°N, longitude 123.4°W, water depth 2165 m) are compiled for the last ~11,300 years and compared with those of ODP 1019 and TN062-O550 from northern California. The relative abundance record of the subtropical...
Authors
John A. Barron, Jason A. Addison, Linda E. Heusser, David Bukry, Valerie Evelyn Schwartz, Amy Wagner
The Miocene stratigraphy of the Laberinto area (Río Ica Valley) and its bearing on the geological history of the East Pisco Basin (south-central Peru) The Miocene stratigraphy of the Laberinto area (Río Ica Valley) and its bearing on the geological history of the East Pisco Basin (south-central Peru)
Global sea-level changes and substantial vertical displacement along the Monte Grande Fault (MGF) in the lower Río Ica Valley of south-central Peru influenced the accumulation of bioclast-bearing and diatom-bearing Miocene siliciclastic sediments in an area of the East Pisco forearc basin (EPB) colloquially known as Laberinto. Two depositional hiatuses in the Laberinto area (∼17–14 Ma,...
Authors
Thomas J. Devries, John A. Barron, Mario Urbina-Schmitt, Diana Ochoa, Raúl Esperante, Lawrence W. Snee
A North American Hydroclimate Synthesis (NAHS) of the Common Era A North American Hydroclimate Synthesis (NAHS) of the Common Era
This study presents a synthesis of century-scale hydroclimate variations in North America for the Common Era (last 2000 years) using new age models of previously published multiple proxy-based paleoclimate data. This North American Hydroclimate Synthesis (NAHS) examines regional hydroclimate patterns and related environmental indicators, including vegetation, lake water elevation, stream...
Authors
Jessica R. Rodysill, Lesleigh Anderson, Thomas M. Cronin, Miriam C. Jones, Robert S. Thompson, David B. Wahl, Debra A. Willard, Jason A. Addison, Jay R. Alder, Katherine H. Anderson, Lysanna Anderson, John A. Barron, Christopher E. Bernhardt, Steven W. Hostetler, Natalie M. Kehrwald, Nicole Khan, Julie N. Richey, Scott W. Starratt, Laura E. Strickland, Michael Toomey, Claire C. Treat, G. Lynn Wingard
By
Water Resources Mission Area, Ecosystems Land Change Science Program, Energy Resources Program, Groundwater and Streamflow Information Program, Mineral Resources Program, National Laboratories Program, Science and Decisions Center, Florence Bascom Geoscience Center, Geology, Minerals, Energy, and Geophysics Science Center, Geosciences and Environmental Change Science Center, St. Petersburg Coastal and Marine Science Center
Evaluation of hypotheses for right-lateral displacement of Neogene strata along the San Andreas Fault between Parkfield and Maricopa, California Evaluation of hypotheses for right-lateral displacement of Neogene strata along the San Andreas Fault between Parkfield and Maricopa, California
We used geological field studies and diatom biostratigraphy to test a published hypothesis that Neogene marine siliceous strata in the Maricopa and Parkfield areas, located on opposite sides of the San Andreas Fault, were formerly contiguous and then were displaced by about 80–130 kilometers (km) of right-lateral slip along the fault. In the Maricopa area on the northeast side of the San...
Authors
Richard G. Stanley, John A. Barron, Charles L. Powell
A Holocene record of ocean productivity and upwelling from the northern California continental slope A Holocene record of ocean productivity and upwelling from the northern California continental slope
The Holocene upwelling history of the northern California continental slope is examined using the high-resolution record of TN062-O550 (40.9°N, 124.6°W, 550 m water depth). This 7-m-long marine sediment core spans the last ∼7500 years, and we use it to test the hypothesis that marine productivity in the California Current System (CCS) driven by coastal upwelling has co-varied with...
Authors
Jason A. Addison, John A. Barron, Bruce P. Finney, Jennifer E. Kusler, David Bukry, Linda E. Heusser, Clark R. Alexander
High-resolution climate of the past ∼7300 years of coastal northernmost California: Results from diatoms, silicoflagellates, and pollen High-resolution climate of the past ∼7300 years of coastal northernmost California: Results from diatoms, silicoflagellates, and pollen
Piston core TN062-O550, collected about 33 km offshore of Eureka, California, contains a high-resolution record of the climate and oceanography of coastal northernmost California during the past ∼7.34 kyr. Chronology established by nine AMS ages on a combination of planktic foraminifers, bivalve shell fragments, and wood yields a mean sedimentation rate of 103 cm kyr−1. Marine proxies...
Authors
John A. Barron, David Bukry, Linda E. Heusser, Jason A. Addison, Clark R. Alexander