Publications
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Time-series photographs of the sea floor in western Massachusetts Bay: June 1998 to May 1999 Time-series photographs of the sea floor in western Massachusetts Bay: June 1998 to May 1999
This report presents time-series photographs of the sea floor obtained from an instrumented tripod deployed at Site A in western Massachusetts Bay (42° 22.6' N., 70? 47.0' W., 30 m water depth, figure 1) from June 1998 through May 1999. Site A is approximately 1 km south of an ocean outfall that began discharging treated sewage effluent from the Boston metropolitan area into...
Authors
Bradford Butman, P. Soupy Alexander, Michael H. Bothner
Localization and physical properties experiments conducted by Spirit at Gusev crater Localization and physical properties experiments conducted by Spirit at Gusev crater
The precise location and relative elevation of Spirit during its traverses from the Columbia Memorial station to Bonneville crater were determined with bundle-adjusted retrievals from rover wheel turns, suspension and tilt angles, and overlapping images. Physical properties experiments show a decrease of 0.2% per Mars solar day in solar cell output resulting from deposition of airborne...
Authors
R. E. Arvidson, R. C. Anderson, P. Bartlett, J.F. Bell, D. Blaney, P. R. Christensen, P. Chu, L. Crumpler, K. Davis, B.L. Ehlmann, R. Fergason, M.P. Golombek, S. Gorevan, J. A. Grant, R. Greeley, E.A. Guinness, A. F. C. Haldemann, Kenneth E. Herkenhoff, J. Johnson, G. Landis, R. Li, R. Lindemann, H. McSween, D. W. Ming, T. Myrick, L. Richter, F.P. Seelos, S. W. Squyres, R.J. Sullivan, A. Wang, Jim Wilson
Evidence for liquefaction identified in peeled slices of Holocene deposits along the Lower Columbia River, Washington Evidence for liquefaction identified in peeled slices of Holocene deposits along the Lower Columbia River, Washington
Peels made from 10 geoslices beneath a riverbank at Washington's Hunting Island, 45 km inland from the Pacific coast, aid in identifying sand that liquefied during prehistoric earthquakes of estimated magnitude 8-9 at the Cascadia subduction zone. Each slice was obtained by driving sheetpile and a shutter plate to depths of 6-8 m. The resulting sample, as long as 8 m, had a trapezoidal...
Authors
K. Takada, B.F. Atwater
Geochemical constraints on possible subduction components in lavas of Mayon and Taal Volcanoes, Southern Luzon, Philippines Geochemical constraints on possible subduction components in lavas of Mayon and Taal Volcanoes, Southern Luzon, Philippines
Mayon is the most active volcano along the east margin of southern Luzon, Philippines. Petrographic and major element data indicate that Mayon has produced a basaltic to andesitic lava series by fractional crystallization and magma mixing. Trace element data indicate that the parental basalts came from a heterogeneous mantle source. The unmodified composition of the mantle wedge is...
Authors
P.R. Castillo, C. G. Newhall
Stress field variations in the Swiss Alps and the northern Alpine foreland derived from inversion of fault plane solutions Stress field variations in the Swiss Alps and the northern Alpine foreland derived from inversion of fault plane solutions
This study is devoted to a systematic analysis of the state of stress of the central European Alps and northern Alpine foreland in Switzerland based on focal mechanisms of 138 earthquakes with magnitudes between 1 and 5. The most robust feature of the results is that the azimuth of the minimum compressive stress, S3, is generally well constrained for all data subsets and always lies in...
Authors
U. Kastrup, M.L. Zoback, N. Deichmann, Kenneth F. Evans, D. Giardini, A.J. Michael
Dynamic rupture modeling of the transition from thrust to strike-slip motion in the 2002 Denali fault earthquake, Alaska Dynamic rupture modeling of the transition from thrust to strike-slip motion in the 2002 Denali fault earthquake, Alaska
We use three-dimensional dynamic (spontaneous) rupture models to investigate the nearly simultaneous ruptures of the Susitna Glacier thrust fault and the Denali strike-slip fault. With the 1957 Mw 8.3 Gobi-Altay, Mongolia, earthquake as the only other well-documented case of significant, nearly simultaneous rupture of both thrust and strike-slip faults, this feature of the 2002 Denali...
Authors
Brad T. Aagaard, G. Anderson, K.W. Hudnut
The final Galileo SSI observations of Io: Orbits G28-I33 The final Galileo SSI observations of Io: Orbits G28-I33
We present the observations of Io acquired by the Solid State Imaging (SSI) experiment during the Galileo Millennium Mission (GMM) and the strategy we used to plan the exploration of Io. Despite Galileo's tight restrictions on data volume and downlink capability and several spacecraft and camera anomalies due to the intense radiation close to Jupiter, there were many successful SSI...
Authors
Elizabeth P. Turtle, Laszlo P. Keszthelyi, Alfred S. McEwen, Jani Radebaugh, Moses P. Milazzo, Damon P. Simonelli, Paul E. Geissler, David A. Williams, Jason Perry, Windy L. Jaeger, Kenneth P. Klaasen, H. Herbert Breneman, Tilmann Denk, Cynthia B. Phillips
Reaction rim growth on olivine in silicic melts: Implications for magma mixing Reaction rim growth on olivine in silicic melts: Implications for magma mixing
Finely crystalline amphibole or pyroxene rims that form during reaction between silicic host melt and cognate olivine xenocrysts, newly introduced during magma mixing events, can provide information about the timing between mixing and volcanic eruptions. We investigated rim growth experimentally by placing forsteritic olivine in rhyolitic and rhyodacitic melts for times between 25 and...
Authors
Michelle L. Coombs, James E. Gardner
Age of the Rockland tephra, western USA Age of the Rockland tephra, western USA
The age of the Rockland tephra, which includes an ash-flow tuff south and west of Lassen Peak in northern California and a widespread ash-fall deposit that produced a distinct stratigraphic marker in western North America, is constrained to 565,000 to 610,000 yr by 40Ar/39Ar and U–Pb dating. 40Ar/39Ar ages on plagioclase from pumice in the Rockland have a weighted mean age of 609,000 ±...
Authors
M. A. Lanphere, D.E. Champion, M.A. Clynne, J. B. Lowenstern, A.M. Sarna-Wojcicki, J. L. Wooden
Pancam multispectral imaging results from the Spirit Rover at Gusev crater Pancam multispectral imaging results from the Spirit Rover at Gusev crater
Panoramic Camera images at Gusev crater reveal a rock-strewn surface interspersed with high- to moderate-albedo fine-grained deposits occurring in part as drifts or in small circular swales or hollows. Optically thick coatings of fine-grained ferric iron-rich dust dominate most bright soil and rock surfaces. Spectra of some darker rock surfaces and rock regions exposed by brushing or...
Authors
J.F. Bell, S. W. Squyres, R. E. Arvidson, H.M. Arneson, D. Bass, D. Blaney, N. Cabrol, W. Calvin, J. Farmer, W. H. Farrand, W. Goetz, M. Golombek, J. A. Grant, R. Greeley, E. Guinness, A. G. Hayes, M.Y.H. Hubbard, Kenneth E. Herkenhoff, M. J. Johnson, J. R. Johnson, J. Joseph, K.M. Kinch, M.T. Lemmon, R. Li, M.B. Madsen, J.N. Maki, M. Malin, E. McCartney, S. McLennan, H.Y. McSween, D. W. Ming, J.E. Moersch, R.V. Morris, E.Z.N. Dobrea, T. J. Parker, J. Proton, J. W. Rice, F. Seelos, J. Soderblom, Laurence A. Soderblom, J. N. Sohl-Dickstein, R.J. Sullivan, M.J. Wolff, A. Wang
Surface changes on Io during the Galileo mission Surface changes on Io during the Galileo mission
A careful survey of Galileo SSI global monitoring images revealed more than 80 apparent surface changes that took place on Io during the 5 year period of observation, ranging from giant plume deposits to subtle changes in the color or albedo of Patera surfaces. Explosive volcanic activity was discovered at four previously unrecognized centers: an unnamed patera to the south of Karei that...
Authors
Paul E. Geissler, Alfred McEwen, Cynthia B. Phillips, Laszlo P. Keszthelyi, John Spencer
Comparison of USGS and DLR topographic models of Comet Borrelly and photometric applications Comparison of USGS and DLR topographic models of Comet Borrelly and photometric applications
Stereo analysis of images obtained during the 2001 flyby of Comet Borrelly by NASA's Deep Space 1 (DS1) probe allows us to quantify the shape and photometric behavior of the nucleus. The shape is complex, with planar facets corresponding to the dark, mottled regions of the surface whereas the bright, smooth regions are convexly curved. The photometric as well as textural differences...
Authors
Randolph L. Kirk, Elpitha Howington-Kraus, Laurence A. Soderblom, Bernd Giese, Jurgen Oberst