Motion of the Scotia sea plates
C. Thomas, R. Livermore, F. Pollitz
2003, Geophysical Journal International (155) 789-804
Earthquake data from the Scotia Arc to early 2002 are reviewed in the light of satellite gravity and other data in order to derive a model for the motion of plates in the Scotia Sea region. Events with magnitude ???5, which occurred on or near the boundaries of the Scotia...
Hydrological response to earthquakes in the Haibara well, central Japan - I. Groundwater level changes revealed using state space decomposition of atmospheric pressure, rainfall and tidal responses
N. Matsumoto, G. Kitagawa, E.A. Roeloffs
2003, Geophysical Journal International (155) 885-898
For the groundwater level observed at the Haibara well, Shizuoka Prefecture, central Japan, time series analysis using state-space modelling is applied to extract hydrological anomalies related to earthquakes. This method can decompose observed groundwater level time series into five components: atmospheric pressure, tidal, and precipitation responses, observation noise, and residual...
Quantitative analysis of seismic fault zone waves in the rupture zone of the 1992 Landers, California, earthquake: Evidence for a shallow trapping structure
Z. Peng, Y. Ben-Zion, A.J. Michael, L. Zhu
2003, Geophysical Journal International (155) 1021-1041
We analyse quantitatively a waveform data set of 238 earthquakes recorded by a dense seismic array across and along the rupture zone of the 1992 Landers earthquake. A grid-search method with station delay corrections is used to locate events that do not have catalogue locations. The quality of fault zone...
Genetic Algorithm Calibration of Probabilistic Cellular Automata for Modeling Mining Permit Activity
S.J. Louis, G. L. Raines
2003, Conference Paper, Proceedings of the International Conference on Tools with Artificial Intelligence
We use a genetic algorithm to calibrate a spatially and temporally resolved cellular automata to model mining activity on public land in Idaho and western Montana. The genetic algorithm searches through a space of transition rule parameters of a two dimensional cellular automata model to find rule parameters that fit...
Mars Exploration Rover Athena Panoramic Camera (Pancam) investigation
J.F. Bell III, S. W. Squyres, Kenneth E. Herkenhoff, J.N. Maki, H.M. Arneson, D. Brown, S.A. Collins, A. Dingizian, S.T. Elliot, E.C. Hagerott, A. G. Hayes, M. J. Johnson, J. R. Johnson, J. Joseph, K. Kinch, M.T. Lemmon, R.V. Morris, L. Scherr, M. Schwochert, M.K. Shepard, G.H. Smith, J. N. Sohl-Dickstein, R.J. Sullivan, W.T. Sullivan, M. Wadsworth
2003, Journal of Geophysical Research E: Planets (108)
The Panoramic Camera (Pancam) investigation is part of the Athena science payload launched to Mars in 2003 on NASA's twin Mars Exploration Rover (MER) missions. The scientific goals of the Pancam investigation are to assess the high‐resolution morphology, topography, and geologic context of each MER landing site, to obtain color...
Budgeting postglacial sedimentation history on the Santa Cruz, California mid-continental shelf
E. E. Grossman, S.L. Eittreim, D.M. Hanes, M.E. Field, B. D. Edwards, S.J. Fallon, R. J. Anima
2003, Conference Paper, Oceans Conference record
High-resolution seismic reflection profiling and surface texture mapping of the central California continental shelf, reveal a prominent subsurface reflector interpreted as a low stand erosion surface and an overlying mudbelt that covers 421 km2 of the mid-shelf in depths of 40-90 m. Radiometric and sedimentologic analyses of samples from vibracores...
Seasonal and spatial distribution of bacterial biomass and the percentage of viable cells in a reservoir of Alabama
T.E. Tietjen, R.G. Wetzel
2003, Journal of Plankton Research (25) 1521-1534
Spatial community dynamics of bacterioplankton were evaluated along the length of the former stream channel of Elledge Lake, a small reservoir in western Alabama. The reservoir was strongly stratified from April to October with up to a 10??C temperature difference across the 1 m deep metalimnion. Bacterial biomass was highest...
Supra-subduction zone extensional magmatism in Vermont and adjacent Quebec: Implications for early Paleozoic Appalachian tectonics
J. Kim, R. Coish, M. Evans, G. Dick
2003, Geological Society of America Bulletin (115) 1552-1569
Metadiabasic intrusions of the Mount Norris Intrusive Suite occur in fault-bounded lithotectonic packages containing Stowe, Moretown, and Cram Hill Formation lithologies in the northern Vermont Rowe-Hawley belt, a proposed Ordovician arc-trench gap above an east-dipping subduction zone. Rocks of the Mount Norris Intrusive Suite are characteristically massive and weakly foliated,...
Using a 1200 kHz workhorse ADCP with mode 12 to measure near bottom mean currents
M. Martini
Rizoli J.A., editor(s)
2003, Conference Paper, Proceedings of the IEEE Working Conference on Current Measurement
Using high frequency Acoustic Doppler Current (ADCP) profiling technology, it is possible to make high-resolution measurements of mean current profiles within a few meters of the seabed. In coastal applications, mean current speeds may be 10 cm/s or less, and oscillatory wave currents may exceed 100 cm/s during storm events....
Brittle deformation along the Gulf of Alaska margin in response to Paleocene-Eocene triple junction migration
Peter J. Haeussler, Dwight Bradley, Richard J. Goldfarb
V.B. Sisson, Sarah M. Roeske, Terry L. Pavlis, editor(s)
2003, Book chapter, Geology of a transpressional orogen developed during ridge-trench interaction along the North Pacific margin
A spreading center was subducted diachronously along a 2200 km segment of what is now the Gulf of Alaska margin between 61 and 50 Ma, and left in its wake near-trench intrusions and high-T, low-P metamorphic rocks. Gold-quartz veins and dikes, linked to ridge subduction by geochronological and relative timing...
A comprehensive approach to monitoring volcano deformation as a window on the eruption cycle
D. Dzurisin
2003, Reviews of Geophysics (41) 1-1
Since the 1980 eruption of Mount St. Helens, volcanologists have made considerable progress toward predicting eruptions on the basis of precursors that typically start a few days to several months in advance. Although accurate eruption prediction is by no means routine, it may now be possible in some cases to...
Crustal magnetization and accretion at the Southwest Indian Ridge near the Atlantis II fracture zone, 0-25 Ma
A. Hosford, M. Tivey, T. Matsumoto, H. Dick, Hans Schouten, H. Kinoshita
2003, Journal of Geophysical Research B: Solid Earth (108)
We analyze geophysical data that extend from 0 to 25-Myr-old seafloor on both flanks of the Southwest Indian Ridge (SWIR). Lineated marine magnetic anomalies are consistent and identifiable within the study area, even over seafloor lacking a basaltic upper crust. The full spreading rate of 14 km/Myr has remained nearly...
Reservoir depletion at The Geysers geothermal area, California, shown by four-dimensional seismic tomography
R.C. Gunasekera, G.R. Foulger, B.R. Julian
2003, Journal of Geophysical Research B: Solid Earth (108)
Intensive geothermal exploitation at The Geysers geothermal area, California, induces myriads of small-magnitude earthquakes that are monitored by a dense, permanent, local seismometer network. Using this network, tomographic inversions were performed for the three-dimensional Vp and Vp/Vs structure of the reservoir for April 1991, February 1993, December 1994, October 1996,...
Flood plain and channel dynamics of the Quinault and Queets Rivers, Washington, USA
J. E. O’Connor, M. A. Jones, T.L. Haluska
2003, Geomorphology (51) 31-59
Comparison of historic channel migration rates, modern planform conditions, and overall sediment, wood, and flow conditions and interactions for the Quinault River and Queets River in the western Olympic Peninsula, Washington, reveals decadal- to century-scale interactions between gravel-bed channels and forested flood plains in temperate maritime environments. The downstream...
Surface complexation and precipitate geometry for aqueous Zn(II) sorption on ferrihydrite: II. XANES analysis and simulation
G.A. Waychunas, C. C. Fuller, J.A. Davis, J.J. Rehr
2003, Geochimica et Cosmochimica Acta (67) 1031-1043
X-ray absorption near-edge spectroscopy (XANES) analysis of sorption complexes has the advantages of high sensitivity (10- to 20-fold greater than extended X-ray absorption fine structure [EXAFS] analysis) and relative ease and speed of data collection (because of the short k-space range). It is thus a potentially powerful tool for characterization...
Volcano seismology
B. Chouet
2003, Pure and Applied Geophysics (160) 739-788
A fundamental goal of volcano seismology is to understand active magmatic systems, to characterize the configuration of such systems, and to determine the extent and evolution of source regions of magmatic energy. Such understanding is critical to our assessment of eruptive behavior and its hazardous impacts. With the emergence of...
Evidence for a Battle Mountain-Eureka crustal fault zone, north-central Nevada, and its relation to Neoproterozoic-Early Paleozoic continental breakup
V. J. S. Grauch, B. D. Rodriguez, V. Bankey, J. L. Wooden
2003, Journal of Geophysical Research B: Solid Earth (108)
Combined evidence from gravity, radiogenic isotope, and magnetotelluric (MT) data indicates a crustal fault zone that coincides with the northwest-trending Battle Mountain-Eureka (BME) mineral trend in north-central Nevada, USA. The BME crustal fault zone likely originated during Neoproterozoic-Early Paleozoic rifting of the continent and had a large influence on subsequent...
Patterns and sources of multidecadal oscillations in drought-sensitive tree-ring records from the central and southern Rocky Mountains
S.J. Gray, J.L. Betancourt, C.L. Fastie, S.T. Jackson
2003, Geophysical Research Letters (30) 49-1
Tree-ring records spanning the past seven centuries from the central and southern Rocky Mountains were studied using wavelet analysis to examine multidecadal (>30-70 yr) patterns of drought variation. Fifteen tree-ring series were grouped into five regional composite chronologies based on shared low-frequency behavior. Strong multidecadal phasing of moisture variation was...
Source depth dependence of micro-tsunamis recorded with ocean-bottom pressure gauges: The January 28, 2000 Mw 6.8 earthquake off Nemuro Peninsula, Japan
K. Hirata, H. Takahashi, E. Geist, K. Satake, Y. Tanioka, H. Sugioka, H. Mikada
2003, Earth and Planetary Science Letters (208) 305-318
Micro-tsunami waves with a maximum amplitude of 4-6 mm were detected with the ocean-bottom pressure gauges on a cabled deep seafloor observatory south of Hokkaido, Japan, following the January 28, 2000 earthquake (Mw 6.8) in the southern Kuril subduction zone. We model the observed micro-tsunami and estimate the focal depth...
Surge dynamics coupled to pore-pressure evolution in debris flows
S.B. Savage, R.M. Iverson
Rickenmann D.Chen C.L., editor(s)
2003, Conference Paper, International Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment, Proceedings
Temporally and spatially varying pore-fluid pressures exert strong controls on debris-flow motion by mediating internal and basal friction at grain contacts. We analyze these effects by deriving a one-dimensional model of pore-pressure diffusion explicitly coupled to changes in debris-flow thickness. The new pore-pressure equation is combined with Iverson's (1997) extension...
Incorporating uncertainty into high-resolution groundwater supply models
A. Rahman, S. Hartono, David R. Carlson, C. S. Willson
Mishra S.Mishra S., editor(s)
2003, Conference Paper, Groundwater Quality Modeling and Management Under Uncertinity
Groundwater modeling is a useful tool for evaluating whether an acquifer system is capable of supporting groundwater withdrawals over long periods of time and what effect, if any, such activity will have on the regional flow dynamics as well as on specific public water, agricultural and industrial supplies. An overview...
Landsat multispectral sharpening using a sensor system model and panchromatic image
G.P. Lemeshewsky
Rahman Z.Schowengerdt R.A.Reichenbach S.E., editor(s)
2003, Conference Paper, Proceedings of SPIE - The International Society for Optical Engineering
The thematic mapper (TM) sensor aboard Landsats 4, 5 and enhanced TM plus (ETM+) on Landsat 7 collect imagery at 30-m sample distance in six spectral bands. New with ETM+ is a 15-m panchromatic (P) band. With image sharpening techniques, this higher resolution P data, or as an alternative, the...
Interactions between dissolved organic matter and mercury in the Florida Everglades
G. Aiken, M. Haitzer, J. N. Ryan, K. Nagy, George Aiken
Boutron C.Ferrari C., editor(s)
2003, Journal De Physique. IV : JP (107) 29-32
Experiments were conducted using organic matter isolated from various surface waters in the Florida Everglades to study the interactions between dissolved organic matter (DOM) and Hg (II). Conditional distribution coefficients ( ), obtained using an equilibriurn dialysis ligand exchange method, were strongly affected by...
Melt inclusions come of age: Volatiles, volcanoes, and sorby's legacy
J. B. Lowenstern
2003, Developments in Volcanology (5) 1-21
Despite nearly forty years of modern research on silicate melt inclusions (MI), only within the past 10-15 years have volcanologists and petrologists come to regularly accept their utility for characterizing magmatic systems. Their relatively slow acceptance was likely due to a number of factors including: 1) Lack of reliable analytical...
Environmental Resources Analysis System, A Prototype DSS
M. Flug, S.G. Campbell
P. Bizier, P. DeBarry, editor(s)
2003, Conference Paper, World Water and Environmental Resources Congress
Since the 1960's, an increase in the public's environmental ethics, federal species preservation, water quality protection, and interest in free flowing rivers have evolved to the current concern for stewardship and conservation of natural resources. This heightened environmental awareness creates an appetite for data, models, information management, and systematic analysis...
