Jim E O'Connor
Jim O'Connor is a Research Geologist in the Geology, Minerals, Energy, and Geophysics Science Center. He chiefly works on the geology and geomorphology of the Pacific Northwest.
Jim O’Connor majored in Geological Science at University of Washington and earned his M.S. and Ph.D. degrees at University of Arizona. Since 1991, he has worked at the U.S. Geological Survey, intent on improving understanding of the processes and events that shape the remarkable and diverse landscapes of the Pacific Northwest.
Professional Experience
2014 - present, Research Geologist, U.S. Geological Survey, Portland, Oregon
1996 - present, Adjunct professor, Dept. Geology, Portland State University, Portland, Oregon
1996 - 2014, Research Hydrologist, U.S. Geological Survey, Portland, Oregon
1994 - 1996, Research Hydrologist, U.S. Forest Service Pacific Northwest Research Station, Portland, Oregon
1991 - 1994, National Research Council Post-Doctoral Fellow, U.S. Geological Survey, Cascades Volcano Observatory, Vancouver, Washington
1985 - 1987, Hydrologist, Pima County Dept. Transportation and Flood Control, Tucson, Arizona
Education and Certifications
Ph.D., Geosciences, University of Arizona, 1990
M.S., Geosciencesm University of Arizona, 1985
B.S., Geological Sciences, University of Washington, 1982
Affiliations and Memberships*
1984 - present, Geological Society of America (Fellow)
1985 - present, American Geophysical Union
2015 - present, Sigma Xi
Portland State University
Oregon State University
Science and Products
Filter Total Items: 47
River network and reach‐scale controls on habitat for lamprey larvae in the Umpqua River Basin, Oregon
This study developed a spatially explicit framework to support the conservation of Western Brook Lamprey Lampetra richardsoni and Pacific Lamprey Entosphenus tridentatus in the Umpqua River basin, Oregon. This framework identified locations within the river network likely to support “potential burrowing habitat” for lamprey larvae based on geomorphic conditions and evaluated the overlap of potenti
Authors
Krista Jones, Jason B. Dunham, Jim E. O'Connor, Mackenzie K. Keith, Joseph F. Mangano, Kelly Coates, Travis Mackie
Quantitative paleoflood hydrology
This chapter reviews the paleohydrologic techniques and approaches used to reconstruct the magnitude and frequency of past floods using geological evidence. Quantitative paleoflood hydrology typically leads to two phases of analysis: (1) documentation and assessment of flood physical evidence (paleostage indicators), and (2) relating identified flood evidence to flood discharge, based on hydraulic
Authors
Gerardo Benito, Jim E. O'Connor
The Missoula and Bonneville floods—A review of ice-age megafloods in the Columbia River basin
The Channeled Scabland of eastern Washington State, USA, brought megafloods to the scientific forefront. A 30,000-km2 landscape of coulees and cataracts carved into the region’s loess-covered basalt attests to overwhelming volumes of energetic water. The scarred landscape, garnished by huge boulder bars and far-travelled ice-rafted erratics, spurred J Harlen Bretz’s vigorously disputed flood hypot
Authors
Jim E. O'Connor, Victor R. Baker, Richard B. Waitt, Larry N Smith, Charles M. Cannon, David L. George, Roger P. Denlinger
Preface to historic and paleoflood analyses: New perspectives on climate, extreme flood risk, and the geomorphic effects of large floods
Paleofloods are flood events that occurred prior to instrumented records that are discerned from sedimentary evidence. Historic floods are flood events that predate the instrumented record that have been reconstructed based on evidence provided by historical sources. This special issue presents papers on historic and paleoflood analyses that stemmed from the 5th International Paleoflood Symposium
Authors
Lisa Davis, Tessa M. Harden, Samuel E. Muñoz, Jeanne E. Godaire, Jim E. O'Connor
Conceptualizing ecological responses to dam removal: If you remove it, what's to come?
One of the desired outcomes of dam decommissioning and removal is the recovery of aquatic and riparian ecosystems. To investigate this common objective, we synthesized information from empirical studies and ecological theory into conceptual models that depict key physical and biological links driving ecological responses to removing dams. We define models for three distinct spatial domains: upstre
Authors
J. Ryan Bellmore, George R. Pess, Jeffrey J. Duda, Jim E. O'Connor, Amy E. East, Melissa M. Foley, Andrew C. Wilcox, Jon J. Major, Patrick B. Shafroth, Sarah A. Morley, Christopher S. Magirl, Chauncey W. Anderson, James E. Evans, Christian E. Torgersen, Laura S. Craig
By
Ecosystems Mission Area, Coastal and Marine Hazards and Resources Program, Species Management Research Program, Arizona Water Science Center, Forest and Rangeland Ecosystem Science Center, Fort Collins Science Center, Geology, Minerals, Energy, and Geophysics Science Center, John Wesley Powell Center for Analysis and Synthesis, Oregon Water Science Center, Pacific Coastal and Marine Science Center, Western Fisheries Research Center
Outburst floods provide erodability estimates consistent with long-term landscape evolution
Most current models for the landscape evolution over geological timescales are based on semi-empirical laws that consider riverbed incision proportional to rock erodability (dependent on lithology) and to the work performed by water flow (stream power). However, the erodability values obtained from these models are entangled with poorly known conditions of past climate and streamflow. Here we use
Authors
Daniel Garcia-Castellanos, Jim E. O'Connor
Computational fluid dynamics simulations of the Late Pleistocene Lake Bonneville flood
At approximately 18.0 ka, pluvial Lake Bonneville reached its maximum level. At its northeastern extent it was impounded by alluvium of the Marsh Creek Fan, which breached at some point north of Red Rock Pass (Idaho), leading to one of the largest floods on Earth. About 5320 km3 of water was discharged into the Snake River drainage and ultimately into the Columbia River. We use a 0D model and a 2D
Authors
José M. Abril-Hernández, Raúl Periáñez, Jim E. O'Connor, Daniel Garcia-Castellanos
James Dwight Dana and John Strong Newberry in the US Pacific Northwest: The roots of American fluvialism
Recognition of the power of rivers to carve landscapes transformed geology and geomorphology in the late nineteenth century. Wide acceptance of this concept—then known as “fluvialism”—owes to many factors and people, several associated with exploration of western North America. Especially famous are the federal geographic and geologic surveys of the US Southwest with John Wesley Powell and Grove K
Authors
Jim E. O'Connor
Geomorphic responses to dam removal in the United States – a two-decade perspective
Recent decades have seen a marked increase in the number of dams removed in the United States. Investigations following a number of removals are beginning to inform how, and how fast, rivers and their ecosystems respond to released sediment. Though only a few tens of studies detail physical responses to removals, common findings have begun to emerge. They include: (1) Rivers are resilient and resp
Authors
Jon J. Major, Amy E. East, Jim E. O'Connor, Gordon E. Grant, Andrew C. Wilcox, Christopher S. Magirl, Matthias J. Collins, Desiree D. Tullos
Luminescence dating of paleolake deltas and glacial deposits in Garwood Valley, Antarctica: Implications for climate, Ross ice sheet dynamics, and paleolake duration
The formation of perched deltas and other lacustrine deposits in the McMurdo Dry Valleys of Antarctica is widely considered to be evidence of valley-filling lakes dammed by the grounded Ross Sea ice sheet during the local Last Glacial Maximum, with lake drainage interpreted as a record of grounding line retreat. We used luminescence dating to determine the age of paleolake deltas and glacial tills
Authors
Joseph S. Levy, Tammy M. Rittenour, Andrew G. Fountain, Jim E. O'Connor
10Be dating of late Pleistocene megafloods and Cordilleran Ice Sheet retreat in the northwestern United States
During the late Pleistocene, multiple floods from drainage of glacial Lake Missoula further eroded a vast anastomosing network of bedrock channels, coulees, and cataracts, forming the Channeled Scabland of eastern Washington State (United States). However, the timing and exact pathways of these Missoula floods remain poorly constrained, thereby limiting our understanding of the evolution of this s
Authors
Andrea M. Balbas, Aaron M. Barth, Peter U. Clark, Jorie Clark, Marc A. Caffee, Jim E. O'Connor, Victor R. Baker, Kevin Konrad, Bruce Bjornstad
Prehistoric floods on the Tennessee River—Assessing the use of stratigraphic records of past floods for improved flood-frequency analysis
Stratigraphic analysis, coupled with geochronologic techniques, indicates that a rich history of large Tennessee River floods is preserved in the Tennessee River Gorge area. Deposits of flood sediment from the 1867 peak discharge of record (460,000 cubic feet per second at Chattanooga, Tennessee) are preserved at many locations throughout the study area at sites with flood-sediment accumulation. S
Authors
Tessa M. Harden, Jim E. O'Connor
Science and Products
Filter Total Items: 47
River network and reach‐scale controls on habitat for lamprey larvae in the Umpqua River Basin, Oregon
This study developed a spatially explicit framework to support the conservation of Western Brook Lamprey Lampetra richardsoni and Pacific Lamprey Entosphenus tridentatus in the Umpqua River basin, Oregon. This framework identified locations within the river network likely to support “potential burrowing habitat” for lamprey larvae based on geomorphic conditions and evaluated the overlap of potenti
Authors
Krista Jones, Jason B. Dunham, Jim E. O'Connor, Mackenzie K. Keith, Joseph F. Mangano, Kelly Coates, Travis Mackie
Quantitative paleoflood hydrology
This chapter reviews the paleohydrologic techniques and approaches used to reconstruct the magnitude and frequency of past floods using geological evidence. Quantitative paleoflood hydrology typically leads to two phases of analysis: (1) documentation and assessment of flood physical evidence (paleostage indicators), and (2) relating identified flood evidence to flood discharge, based on hydraulic
Authors
Gerardo Benito, Jim E. O'Connor
The Missoula and Bonneville floods—A review of ice-age megafloods in the Columbia River basin
The Channeled Scabland of eastern Washington State, USA, brought megafloods to the scientific forefront. A 30,000-km2 landscape of coulees and cataracts carved into the region’s loess-covered basalt attests to overwhelming volumes of energetic water. The scarred landscape, garnished by huge boulder bars and far-travelled ice-rafted erratics, spurred J Harlen Bretz’s vigorously disputed flood hypot
Authors
Jim E. O'Connor, Victor R. Baker, Richard B. Waitt, Larry N Smith, Charles M. Cannon, David L. George, Roger P. Denlinger
Preface to historic and paleoflood analyses: New perspectives on climate, extreme flood risk, and the geomorphic effects of large floods
Paleofloods are flood events that occurred prior to instrumented records that are discerned from sedimentary evidence. Historic floods are flood events that predate the instrumented record that have been reconstructed based on evidence provided by historical sources. This special issue presents papers on historic and paleoflood analyses that stemmed from the 5th International Paleoflood Symposium
Authors
Lisa Davis, Tessa M. Harden, Samuel E. Muñoz, Jeanne E. Godaire, Jim E. O'Connor
Conceptualizing ecological responses to dam removal: If you remove it, what's to come?
One of the desired outcomes of dam decommissioning and removal is the recovery of aquatic and riparian ecosystems. To investigate this common objective, we synthesized information from empirical studies and ecological theory into conceptual models that depict key physical and biological links driving ecological responses to removing dams. We define models for three distinct spatial domains: upstre
Authors
J. Ryan Bellmore, George R. Pess, Jeffrey J. Duda, Jim E. O'Connor, Amy E. East, Melissa M. Foley, Andrew C. Wilcox, Jon J. Major, Patrick B. Shafroth, Sarah A. Morley, Christopher S. Magirl, Chauncey W. Anderson, James E. Evans, Christian E. Torgersen, Laura S. Craig
By
Ecosystems Mission Area, Coastal and Marine Hazards and Resources Program, Species Management Research Program, Arizona Water Science Center, Forest and Rangeland Ecosystem Science Center, Fort Collins Science Center, Geology, Minerals, Energy, and Geophysics Science Center, John Wesley Powell Center for Analysis and Synthesis, Oregon Water Science Center, Pacific Coastal and Marine Science Center, Western Fisheries Research Center
Outburst floods provide erodability estimates consistent with long-term landscape evolution
Most current models for the landscape evolution over geological timescales are based on semi-empirical laws that consider riverbed incision proportional to rock erodability (dependent on lithology) and to the work performed by water flow (stream power). However, the erodability values obtained from these models are entangled with poorly known conditions of past climate and streamflow. Here we use
Authors
Daniel Garcia-Castellanos, Jim E. O'Connor
Computational fluid dynamics simulations of the Late Pleistocene Lake Bonneville flood
At approximately 18.0 ka, pluvial Lake Bonneville reached its maximum level. At its northeastern extent it was impounded by alluvium of the Marsh Creek Fan, which breached at some point north of Red Rock Pass (Idaho), leading to one of the largest floods on Earth. About 5320 km3 of water was discharged into the Snake River drainage and ultimately into the Columbia River. We use a 0D model and a 2D
Authors
José M. Abril-Hernández, Raúl Periáñez, Jim E. O'Connor, Daniel Garcia-Castellanos
James Dwight Dana and John Strong Newberry in the US Pacific Northwest: The roots of American fluvialism
Recognition of the power of rivers to carve landscapes transformed geology and geomorphology in the late nineteenth century. Wide acceptance of this concept—then known as “fluvialism”—owes to many factors and people, several associated with exploration of western North America. Especially famous are the federal geographic and geologic surveys of the US Southwest with John Wesley Powell and Grove K
Authors
Jim E. O'Connor
Geomorphic responses to dam removal in the United States – a two-decade perspective
Recent decades have seen a marked increase in the number of dams removed in the United States. Investigations following a number of removals are beginning to inform how, and how fast, rivers and their ecosystems respond to released sediment. Though only a few tens of studies detail physical responses to removals, common findings have begun to emerge. They include: (1) Rivers are resilient and resp
Authors
Jon J. Major, Amy E. East, Jim E. O'Connor, Gordon E. Grant, Andrew C. Wilcox, Christopher S. Magirl, Matthias J. Collins, Desiree D. Tullos
Luminescence dating of paleolake deltas and glacial deposits in Garwood Valley, Antarctica: Implications for climate, Ross ice sheet dynamics, and paleolake duration
The formation of perched deltas and other lacustrine deposits in the McMurdo Dry Valleys of Antarctica is widely considered to be evidence of valley-filling lakes dammed by the grounded Ross Sea ice sheet during the local Last Glacial Maximum, with lake drainage interpreted as a record of grounding line retreat. We used luminescence dating to determine the age of paleolake deltas and glacial tills
Authors
Joseph S. Levy, Tammy M. Rittenour, Andrew G. Fountain, Jim E. O'Connor
10Be dating of late Pleistocene megafloods and Cordilleran Ice Sheet retreat in the northwestern United States
During the late Pleistocene, multiple floods from drainage of glacial Lake Missoula further eroded a vast anastomosing network of bedrock channels, coulees, and cataracts, forming the Channeled Scabland of eastern Washington State (United States). However, the timing and exact pathways of these Missoula floods remain poorly constrained, thereby limiting our understanding of the evolution of this s
Authors
Andrea M. Balbas, Aaron M. Barth, Peter U. Clark, Jorie Clark, Marc A. Caffee, Jim E. O'Connor, Victor R. Baker, Kevin Konrad, Bruce Bjornstad
Prehistoric floods on the Tennessee River—Assessing the use of stratigraphic records of past floods for improved flood-frequency analysis
Stratigraphic analysis, coupled with geochronologic techniques, indicates that a rich history of large Tennessee River floods is preserved in the Tennessee River Gorge area. Deposits of flood sediment from the 1867 peak discharge of record (460,000 cubic feet per second at Chattanooga, Tennessee) are preserved at many locations throughout the study area at sites with flood-sediment accumulation. S
Authors
Tessa M. Harden, Jim E. O'Connor
*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