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.
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
External Links
Science and Products
Geomorphology of the Sprague River Basin
The USGS documents historical and current channel and floodplain processes and conditions to assist management and regulatory agencies in evaluating restoration proposals and designing effective restoration and monitoring strategies for the Sprague River and its principle tributaries. The study involves multiple analyses, including assessments of historical channel change, riparian and...
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,...
Quinault Indian Reservation
The rivers and forests of the Olympic Peninsula have long been important sources of natural resources. For the Quinault Indian Nation of the southwestern Olympic Peninsula, forests and fisheries have been the cultural and economic mainstay for thousands of years. To protect and restore these dwindling resources, the Quinault Indian Nation is undertaking a science-based approach for land...
Geologic map of the greater Portland metropolitan area and surrounding region, Oregon and Washington
The Portland-Vancouver-Hillsboro Metropolitan Area (metro area) has great scenic, natural, and cultural resources and is the major economic hub of Oregon. The metro area is subject to a variety of geologic hazards. Underthrusting of the oceanic plate along the Cascadia plate boundary fault, or megathrust, deforms the leading edge of North America...
Wells, Ray; Haugerud, Ralph A.; Niem, Alan R.; Niem, Wendy A.; Ma, Lina; Evarts, Russell C.; O'Connor, Jim E.; Madin, Ian P.; Sherrod, David R.; Beeson, Marvin H.; Tolan, Terry L.; Wheeler, Karen L.; Hanson, William B.; Sawlan, Michael G.
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...
Benito, Gerardo; Harden, Tessa M.; O'Connor, Jim E. 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. 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...
Levy, Joseph S.; Rittenour, Tammy M.; Fountain, Andrew G.; O'Connor, Jim E. 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
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.