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E. A. Barnett

Publications and source records attributed to E. A. Barnett.

6 recordsLinked to original sources
USGS2011

Connecting the Yakima fold and thrust belt to active faults in the Puget Lowland, Washington

High-resolution aeromagnetic surveys of the Cascade Range and Yakima fold and thrust belt (YFTB), Washington, provide insights on tectonic connections between forearc and back-arc regions of the Cascadia convergent margin. Magnetic surveys were measured at a nominal altitude of 250 m above terrain and along flight lines spaced 400 m apart. Upper crustal rocks in this region have diverse magnetic properties, ranging from highly magnetic rocks of the Miocene Columbia River Basalt Group to weakly magnetic sedimentary rocks of various ages. These distinctive magnetic properties permit mapping of important faults and folds from exposures to covered areas. Magnetic lineaments correspond with mapped Quaternary faults and with scarps identified in lidar (light detection and ranging) topographic data and aerial photography. A two-dimensional model of the northwest striking Umtanum Ridge fault zone, based on magnetic and gravity data and constrained by geologic mapping and three deep wells, suggests that thrust faults extend through the Tertiary section and into underlying pre-Tertiary basement. Excavation of two trenches across a prominent scarp at the base of Umtanum Ridge uncovered evidence for bending moment faulting possibly caused by a blind thrust. Using aeromagnetic, gravity, and paleoseismic evidence, we postulate possible tectonic connections between the YFTB in eastern Washington and active faults of the Puget Lowland. We suggest that faults and folds of Umtanum Ridge extend northwestward through the Cascade Range and merge with the Southern Whidbey Island and Seattle faults near Snoqualmie Pass 35 km east of Seattle. Recent earthquakes (M W ≤ 5.3) suggest that this confluence of faults may be seismically active today.

Washington↗
USGS2009

Earthquake hazards and lifelines in the Interstate 5 urban corridor: Woodburn, Oregon, to Centralia, Washington

The Interstate 5 highway (I-5) corridor, which stretches from Mexico to Canada, is both the main economic artery of the Pacific Northwest and home to the majority of Oregonians and Washingtonians. Accordingly, most regional utility and transportation systems have major components located within the I-5 corridor. For the purposes of this map, we refer to these essential systems as lifeline systems. The Pacific Northwest section of I-5, the I-5 urban corridor, extends from Eugene, Oregon, to the border of Canada. The population of this region is rapidly increasing with the bulk of growth and economic development centered in the cities of Eugene, Salem, and Portland, Oregon, and Olympia, Tacoma, Seattle, Everett, and Bellingham, Washington.

Oregon, Washington↗
USGS2009

Earthquake hazards and lifelines in the Interstate 5 urban corridor: Cottage Grove to Woodburn, Oregon

The Interstate 5 highway (I-5) corridor, which stretches from Mexico to Canada, is both the main economic artery of the Pacific Northwest and home to the majority of Oregonians and Washingtonians. Accordingly, most regional utility and transportation systems have major components located within the I-5 corridor. For the purposes of this map, we refer to these essential systems as lifeline systems. The Pacific Northwest section of I-5, the I-5 urban corridor, extends from Eugene, Oregon, to the border of Canada. The population of this region is rapidly increasing with the bulk of growth and economic development centered in the cities of Eugene, Salem, and Portland, Oregon, and Olympia, Tacoma, Seattle, Everett, and Bellingham, Washington.

Oregon↗
USGS2005

Lifelines and earthquake hazards along the Interstate 5 Urban Corridor: Woodburn, Oregon to Centralia, Washington

The Interstate 5 highway corridor, stretching from Mexico to Canada, is not only the economic artery of the Pacific Northwest, but is also home to the majority of Oregonians and Washingtonians. Accordingly, most regional utility and transportation systems, such as railroads and electrical transmission lines, have major components in the I-5 corridor. The section of I-5 from Cottage Grove, Oregon, to Blaine, Washington, is rapidly urbanizing, with population growth and economic development centered around the cities of Eugene, Salem, Portland, Olympia, Tacoma, Seattle, Everett, and Bellingham. For the purposes of this map, we refer to this area as the I-5 Urban Corridor.

Oregon, Washington↗
USGS2004

Lifelines and Earthquake Hazards in the Interstate 5 Urban Corridor: Cottage Grove to Woodburn, Oregon

The Interstate 5 highway corridor, stretching from Mexico to Canada, is not only the economic artery of the Pacific Northwest, but is also home to the majority of Oregonians and Washingtonians. Accordingly, most regional utility and transportation systems, such as railroads and electrical transmission lines, have major components in the I-5 corridor. The section of I-5 from Cottage Grove, Oregon, to Blaine, Washington, is rapidly urbanizing, with population growth and economic development centered around the cities of Eugene, Salem, Portland, Olympia, Tacoma, Seattle, Everett, and Bellingham. For the purposes of this map, we refer to this area as the I-5 Urban Corridor. This publicaton consists of two large sheets: A map and a text-and-figures poster.

Open-File Report↗