Publications
Publications from the staff of the Geology, Minerals, Energy, and Geophysics Science Center
Filter Total Items: 2357
The Catfish Lake Scarp, Allyn, Washington: Preliminary field data and implications for earthquake hazards posed by the Tacoma fault
The Tacoma fault bounds gravity and aeromagnetic anomalies for 50 km across central Puget lowland from Tacoma to western Kitsap County. Tomography implies at least 6 km of post-Eocene uplift to the north of the fault relative to basinal sedimentary rocks to the south.
Coastlines north of the Tacoma fault rose about 1100 years ago during a large earthquake. Abrupt uplift up to several meters caus
Authors
Brian L. Sherrod, Alan R. Nelson, Harvey M. Kelsey, Thomas M. Brocher, Richard J. Blakely, Craig S. Weaver, Nancy K. Rountree, B. Susan Rhea, Bernard S. Jackson
Cross-sections and maps showing double-difference relocated earthquakes from 1984-2000 along the Hayward and Calaveras faults, California
We present cross-section and map views of earthquakes that occurred from 1984 to 2000 in the vicinity of the Hayward and Calaveras faults in the San Francisco Bay region, California. These earthquakes came from a catalog of events relocated using the double-difference technique, which provides superior relative locations of nearby events. As a result, structures such as fault surfaces and alignmen
Authors
Robert W. Simpson, Russell W. Graymer, Robert C. Jachens, David A. Ponce, Carl M. Wentworth
Environmental assessment
Final report of the Independent US Assessment Team, Section 5.
Authors
Geoffrey S. Plumlee, T.P. Boyle, M.J. Logsdon, R.S. Carr
Geophysical investigation of the Denali fault and Alaska Range orogen within the aftershock zone of the October–November 2002, M = 7.9 Denali fault earthquake
The aftershock zone of the 3 November 2002, M = 7.9 earthquake that ruptured along the right-slip Denali fault in south-central Alaska has been investigated by using gravity and magnetic, magnetotelluric, and deep-crustal, seismic reflection data as well as outcrop geology and earthquake seismology. Strong seismic reflections from within the Alaska Range orogen north of the Denali fault dip as ste
Authors
Michael A. Fisher, Warren J. Nokleberg, N. A. Ratchkovski, Louise Pellerin, Jonathan M.G. Glen, Thomas M. Brocher, J. Booker
Geophysical data reveal the crustal structure of the Alaska range orogen within the aftershock zone of the Mw 7.9 Denali fault earthquake
Geophysical information, including deep-crustal seismic reflection, magnetotelluric (mt), gravity, and magnetic data, cross the aftershock zone of the 3 November 2002 Mw 7.9 Denali fault earthquake. These data and aftershock seismicity, jointly interpreted, reveal the crustal structure of the right-lateral-slip Denali fault and the eastern Alaska Range orogen, as well as the relationship between t
Authors
M. A. Fisher, N. Ratchkovski, Warren Nokleberg, Louise Pellerin, Jonathan M.G. Glen
The Cottage Lake aeromagnetic lineament: A possible onshore extension of the southern Whidbey Island fault, Washington
The northwest-striking southern Whidbey Island fault zone (SWIF) was mapped previously using borehole data and potential-field anomalies on Whidbey Island and marine seismic surveys beneath surrounding waterways. Abrupt subsidence at a coastal marsh on south-central Whidbey Island suggests that the SWIF experienced a MW 6.5 to 7.0 earthquake about 3000 years ago. Southeast of Whidbey Island, a hyp
Authors
Richard J. Blakely, Brian L. Sherrod, Ray E. Wells, Craig S. Weaver, David H. McCormack, Kathy G. Troost, Ralph A. Haugerud
Interpretation of the Seattle Uplift, Washington, as a passive-roof duplex
We interpret seismic lines and a wide variety of other geological and geophysical data to suggest that the Seattle uplift is a passive-roof duplex. A passive-roof duplex is bounded top and bottom by thrust faults with opposite senses of vergence that form a triangle zone at the leading edge of the advancing thrust sheet. In passive-roof duplexes the roof thrust slips only when the floor thrust rup
Authors
Thomas M. Brocher, Richard J. Blakely, Ray Wells
Map showing fossil localities of the Rattlesnake Creek, western and eastern Hayfork, and North Fork Terranes of the Klamath Mountains
No abstract available.
Authors
William P. Irwin, Charles D. Blome
Gravity, magnetic, and high‐precision relocated seismicity profiles suggest a connection between the Hayward and Calaveras Faults, northern California
Gravity, magnetic, and seismicity data profiled across the Hayward Fault Zone were generated as part of ongoing studies to help determine the geologic and tectonic setting of the San Francisco Bay region. These data, combined with previous geophysical studies that indicate that the Hayward Fault Zone dips 75°NE near San Leandro and follows a preexisting structure, reveal a possible direct connecti
Authors
David A. Ponce, Robert W. Simpson, Russell W. Graymer, Robert C. Jachens
Chapter 11 The phosphoria formation: A model for forecasting global selenium sources to the environment
Mining of the Permian Phosphoria Formation — a marine, oil-generating, phosphatic shale — provided the selenium (Se) source implicated in the recent deaths of livestock in southeast Idaho. Field studies and the geohydrologic balance of Se in southeast Idaho confirm risk to animals from exposure to Se through leaching of mined waste shale into streams, discharge of regional drainage, and impoundmen
Authors
Theresa S. Presser, David Z. Piper, Kenneth J. Bird, J. P. Skorupa, S. J. Hamilton, S. J. Detwiler, M.A. Huebner
Chapter 14 Rex Chert member of the Permian Phosphoria Formation: Composition, with emphasis on elements of environmental concern
We present bulk chemical and mineralogical compositions, as well as petrographic and outcrop descriptions, of rocks collected from three measured outcrop sections of the Rex Chert Member of the Phosphoria Formation in southeast Idaho. The three measured sections were chosen from 10 outcrops of Rex Chert that were described in the field. The Rex Chert overlies the Meade Peak Phosphatic Shale Member
Authors
James R. Hein, B.R. McIntyre, R.B. Perkins, David Z. Piper, J. G. Evans
Chapter 4 The meade peak member of the phosphoria formation: Temporal and spatial variations in sediment geochemistry
Variations in the geochemistry of rocks from the Meade Peak Member of the Phosphoria Formation were examined using ratios of elements associated with either the +terrigenous or marine sediment fractions. Inter-element relationships in the terrigenous fraction appear useful for chemo-stratigraphic correlation. A sharp decrease upsection in K2O/AI2O3 ratios occurs in the lower half of all but the mo
Authors
R.B. Perkins, David Z. Piper