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Full-Text Articles in Physical Sciences and Mathematics
Vsp Traveltime Inversion: Near-Surface Issues, Geoff J. M. Moret, William P. Clement, Michael D. Knoll, Warren Barrash
Vsp Traveltime Inversion: Near-Surface Issues, Geoff J. M. Moret, William P. Clement, Michael D. Knoll, Warren Barrash
Geosciences Faculty Publications and Presentations
P-wave velocity information obtained from vertical seismic profiles (VSPs) can be useful in imaging subsurface structure, either by directly detecting changes in the subsurface or as an aid to the interpretation of seismic reflection data. In the shallow subsurface, P-wave velocity can change by nearly an order of magnitude over a short distance, so curved rays are needed to accurately model VSP traveltimes. We used a curved-ray inversion to estimate the velocity profile and the discrepancy principle to estimate the data noise level and to choose the optimum regularization parameter. The curved-ray routine performed better than a straight-ray inversion for …
Geology Across And Under The Western Snake River Plain, Idaho: Owyhee Mountains To The Boise Foothills, Spencer H. Wood
Geology Across And Under The Western Snake River Plain, Idaho: Owyhee Mountains To The Boise Foothills, Spencer H. Wood
Geosciences Faculty Publications and Presentations
This 1-day field trip is a transect across the western Snake River Plain (fig. 1). The western plain is a continental- rift structure, 300 km long and 70 km wide. It is bounded and internally faulted by northwest-trending normal faults. The western Snake River Plain has a different orientation and structure than the eastern plain. The eastern plain is a curious downwarp related to magmatism and extension along the track of the Yellowstone hot spot (fig. 2). The faulted basin of the western plain began forming about 12 m.y. ago, and much of the relief was completed by 9 Ma. …
Mae Sae Basin And Wiang Nong Lom: Radiocarbon Dating And Relation To The Active Strike-Slip Mae Chan Fault, Northern Thailand, Spencer H. Wood, Fongsaward S. Singharajwarapan, Tharaporn Bundarnsin, Eric Rothwell
Mae Sae Basin And Wiang Nong Lom: Radiocarbon Dating And Relation To The Active Strike-Slip Mae Chan Fault, Northern Thailand, Spencer H. Wood, Fongsaward S. Singharajwarapan, Tharaporn Bundarnsin, Eric Rothwell
Geosciences Faculty Publications and Presentations
The Mai Sai basin and the Wiang Nong Lom swamp lie north of, and adjacent to, the northeast-trending Mae Chan fault, which is a left -lateral strike-slip fault in northernmost Thailand. The sediment in the Mae Sai basin is about 600 meters thick. The Mae Sai basin has an anticlinal fold below a 390-meter depth. This fold is buried by broadly downwarped sediment. In the Wiang Nong Lom swamp, sediment is about 170 meters thick. Radiocarbon ages from a 2.7-meter auger hole at Ko Mae Mai in the Wiang Nong Lom swamp show that 0.5 meter of sediment accumulated in …
Terminal Moraine Remnants Of The Trail Creek Glacier Northeast Of Sun Valley, Idaho, Eric L. Rothwell, Spencer H. Wood
Terminal Moraine Remnants Of The Trail Creek Glacier Northeast Of Sun Valley, Idaho, Eric L. Rothwell, Spencer H. Wood
Geosciences Faculty Publications and Presentations
This optional excursion is 8 miles on paved road from the center of Ketchum (Main Street and Sun Valley Road traffic light), northeast through Sun Valley along the Trail Creek Road (fig. 1). A short walk of 10 minutes takes you to the crests of two moraines of very different ages. Here we view and discuss calcareous soils developed into the deposits, the pretty weathering-rinds developed on the sandstone cobbles, and ages of Pinedale and Bull Lake advances. During the Quaternary, an extensive system of mountain glaciers accumulated in the Pioneer and Boulder Mountains and flowed down valleys emanating from …
Fire And Ice In Central Idaho: Modern And Holocene Fires, Debris Flows, And Climate In The Payette River Basin, And Quaternary And Glacial Geology In The Sawtooth Mountains, Jennifer L. Pierce, Grant A. Meyer, Glenn D. Thackray, Spencer H. Wood, Kari Lundeen, Jennifer A. Borgert, Eric Rothwell
Fire And Ice In Central Idaho: Modern And Holocene Fires, Debris Flows, And Climate In The Payette River Basin, And Quaternary And Glacial Geology In The Sawtooth Mountains, Jennifer L. Pierce, Grant A. Meyer, Glenn D. Thackray, Spencer H. Wood, Kari Lundeen, Jennifer A. Borgert, Eric Rothwell
Geosciences Faculty Publications and Presentations
This 2-day trip will highlight recent fire and storm-related debris flows in the Payette River region, Holocene records of fires and fire-related sedimentation events preserved in alluvial fan stratigraphic sequences, and geomorphology and geology of alpine glaciations in the spectacular Sawtooth Mountains and Stanley Basin of central Idaho. Storm events and associated scour following recent fires in the South Fork Payette basin have exposed Holocene fire-related debris-flow deposits, flood sediments, and other alluvial fan-building deposits that yield insights into Holocene environmental change. Moraine characteristics and sediment cores from the southeastern Sawtooth Mountains and Stanley Basin provide evidence of late Pleistocene …