Jim E O'Connor
Jim O'Connor is a Research Geologist in the Geology, Minerals, Energy, and Geophysics Science Center. He received a Ph.D. and M.S. in Geosciences from University of Arizona, and a BS in Geological Sciences from University of Washington. Since joinging the USGS in 1991, he has studied surface processes and Quaternary geology, chiefly in the U.S. Pacific Northwest.
Biography
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:
- Ph.D., Geosciences, University of Arizona, 1990
- M.S., Geosciencesm University of Arizona, 1985
- B.S., Geological Sciences, University of Washington, 1982
Affiliations:
- 1984 - present, Geological Society of America (Fellow)
- 1985 - present, American Geophysical Union
- 2015 - present, Sigma Xi
Non-USGS Partners
- Portland State University
- Oregon State University
Science and Products
Dam removal: synthesis of ecological and physical responses
Dam decommissioning is rapidly emerging as an important river restoration strategy in the U.S., with several major removals recently completed or in progress. But few studies have evaluated the far-reaching consequences of these significant environmental perturbations, especially those resulting from removals of large (>10-15 m tall) structures during the last decade. In particular,...
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...
Davis, Lisa; Harden, Tessa M.; Muñoz, Samuel E.; Godaire, Jeanne E.; O'Connor, Jim E. 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...
Bellmore, J. Ryan; Pess, George R.; Duda, Jeffrey J.; O'Connor, Jim E.; East, Amy E.; Foley, Melissa M.; Wilcox, Andrew C.; Major, Jon J.; Shafroth, Patrick B.; Morley, Sarah A.; Magirl, Christopher S.; Anderson, Chauncey W.; Evans, James E.; Torgersen, Christian E.; Craig, Laura S. 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...
Garcia-Castellanos, Daniel; O'Connor, Jim E. 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...
Abril-Hernández, José M.; Periáñez, Raúl; O'Connor, Jim E.; Garcia-Castellanos, Daniel 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...
O'Connor, Jim E. 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...
Tsutsumi, Daizo; Laronne, Jonathan B.; Major, Jon J.; East, Amy E.; O'Connor, Jim E.; Grant, Gordon E.; Wilcox, Andrew C.; Magirl, Christopher S.; Collins, Matthias J.; Tullos, Desiree D. 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...
Balbas, Andrea M.; Barth, Aaron M.; Clark, Peter U.; Clark, Jorie; Caffee, Marc A.; O'Connor, Jim E.; Baker, Victor R.; Konrad, Kevin; Bjornstad, Bruce
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...
Harden, Tessa M.; O'Connor, Jim E. The Bonneville Flood—A veritable débâcle: Chapter 6
The Bonneville Flood was one of the largest floods on Earth. First discovered by G.K. Gilbert in the 1870s during his inspection of the outlet at Red Rock Pass, it was rediscovered in the 1950s by Harold Malde and coworkers, leading to mapping and assessment of spectacular flood features along Marsh Creek, Portneuf River, and Snake River for over...
O'Connor, Jim E.
Geologic map of the Vancouver and Orchards quadrangles and parts of the Portland and Mount Tabor quadrangles, Clark County, Washington, and Multnomah County, Oregon
IntroductionThis is a 1:24,000-scale geologic map of the Vancouver and Orchards quadrangles and parts of the Portland and Mount Tabor quadrangles in the States of Washington and Oregon. The map area is within the Portland Basin and includes most of the city of Vancouver, Washington; parts of Clark County, Washington; and a small part of...
O'Connor, Jim E.; Cannon, Charles M.; Mangano, Joseph F.; Evarts, Russell C. Plugs or flood-makers? the unstable landslide dams of eastern Oregon
Landslides into valley bottoms can affect longitudinal profiles of rivers, thereby influencing landscape evolution through base-level changes. Large landslides can hinder river incision by temporarily damming rivers, but catastrophic failure of landslide dams may generate large floods that could promote incision. Dam stability therefore strongly...
Safran, Elizabeth B.; O'Connor, Jim E.; Ely, Lisa L.; House, P. Kyle; Grant, Gordon E.; Harrity, Kelsey; Croall, Kelsey; Jones, Emily
Geomorphic and vegetation processes of the Willamette River floodplain, Oregon: current understanding and unanswered science questions
This report summarizes the current understanding of floodplain processes and landforms for the Willamette River and its major tributaries. The area of focus encompasses the main stem Willamette River above Newberg and the portions of the Coast Fork Willamette, Middle Fork Willamette, McKenzie, and North, South and main stem Santiam Rivers...
Wallick, J. Rose; Jones, Krista L.; O'Connor, Jim E.; Keith, Mackenzie K.; Hulse, David; Gregory, Stanley V.